Volume 8 - 2017 | https://doi.org/10.3389/fmicb.2017.01063
The emergence of new microbial pathogens can result in destructive outbreaks
since their hosts have limited resistance and pathogens may be excessively aggressive
Described as the major ecological incident of the twentieth century
caused by ascomycete fungi from the Ophiostoma genus
has caused a significant decline in elm tree populations (Ulmus sp.) in North America and Europe
Genome sequencing of the two main causative agents of Dutch elm disease (Ophiostoma ulmi and Ophiostoma novo-ulmi)
along with closely related species with different lifestyles
allows for unique comparisons to be made to identify how pathogens and virulence determinants have emerged
Among several established virulence determinants
secondary metabolites (SMs) have been suggested to play significant roles during phytopathogen infection
the secondary metabolism of Dutch elm pathogens remains almost unexplored
and little is known about how SM biosynthetic genes are organized in these species
To better understand the metabolic potential of O
we performed a deep survey and description of SM biosynthetic gene clusters (BGCs) in these species and assessed their conservation among eight species from the Ophiostomataceae family
a fujikurin-like gene cluster (OpPKS8) was unique to Dutch elm pathogens
Phylogenetic analysis revealed that orthologs for this gene cluster are widespread among phytopathogens and plant-associated fungi
suggesting that OpPKS8 may have been horizontally acquired by the Ophiostoma genus
the detailed identification of several BGCs paves the way for future in-depth research and supports the potential impact of secondary metabolism on Ophiostoma genus’ lifestyle
This information allows for unique comparisons to be made between species to highlight putative virulence determinants in DED pathogens
Dutch elm disease species are promising models to study the impact of invasive species and the evolution and adaptation to new niches
in view of the success and persistence of these pathogens in the environment
it is reasonable to propose that SMs may assist in the infection process of DED pathogens
secondary metabolism and genes enrolled in SM production are virtually unexplored in the Ophiostoma genus and Ophiostomataceae family
we assessed the conservation of BGCs and related genes identified within the eight available Ophiostomataceae family genomes
a specific PKS BGC (OpPKS8) was conserved only in DED pathogens and was absent in other members of the Ophiostomataceae family
Through phylogenetic inference and comparative genomic analyses
we showed that this cluster may have been horizontally acquired by DED pathogens
orthologs for this BGC were found in several plant-associated fungi
which supports a putative role for the products of this gene cluster in phytopathogenic infection
Corresponding amino acid sequences were aligned with the predicted OpPKS8 backbone gene products from O
Genes that satisfied the previously fixed cutoffs were included in further analyses
and a phylogenetic tree was constructed using PhyML 3.1 with 100 bootstrap replicates (alignment shown in Supplementary Data Sheet 2)
A logical diagram describing the step-by-step process and the connections between methodologies applied in this section is shown in Supplementary Figure 2
based primarily on backbone gene conservation (e-value < 1 × 10-5
These results indicate that the SM potential is remarkably similar between Ophiostomataceae family members
two BGCs were found only in the Ophiostoma genus: OpOTHER3 (OphioH327gp1586) was identified in O
while OpPKS8 is exclusive to DED pathogens
To further confirm the absence of OpPKS8 in O
the vicinities of the OpPKS8 locus were explored
The results confirmed the absence of the OpPKS8 gene cluster in O
as several genes in the vicinity were conserved despite the absence of OpPKS8 (Supplementary Figure 4)
Considering that no putative BGCs have been functionally characterized in DED pathogens to date
we employed comparative genomics to determine the likely final products of these BGCs
These comparisons revealed three interesting BGCs that exhibited previously characterized orthologous gene clusters in other species and which were putatively linked with the biosynthesis of a fujikurin-like compound (OpPKS8)
crassa and the Ophiostomataceae family species are grouped in the same class
which may indicate that proteins with similar functions to those of N
crassa could represent the final product of the OpPKS10 backbone gene
and that these similar proteins could act in the biosynthesis of similar metabolites
Synteny comparison between the type III PKS locus in DED pathogens and in N
crassa did not reveal extensive conservation (Supplementary Figure 4)
suggesting that it might not be grouped in a biosynthetic cluster
CASSIS was unable to discriminate homologous regulatory sequences between type III PKS of DED pathogens and neighboring genes
This clustering of the ferricrocin ortholog backbone gene and the L-ornithine N5-oxygenase gene suggests
that DED pathogens utilize a siderophore biosynthesis pathway that is similar to other model fungi
we hypothesize that the products of OpNRPS1 BGC modulate iron dynamics in DED pathogens
Putative fujikurin and fujikurin-like compound cluster (OpPKS8) conservation and synteny
The OpPKS8 cluster from DED pathogens resembled the characterized fujikurin cluster from F
fujikuroi IMI 58289 (36–68% identity in protein-by-protein comparisons of BGC constituent genes)
and putative BGCs from Scedosporium apiospermum (66–84% identity in protein-by-protein comparisons of BGC constituent genes)
Aureobasidium pullulans (58–80% in protein-by-protein comparisons of BGC constituent genes)
and Setosphaeria turcica (66–70% identity in protein-by-protein comparisons of BGC constituent genes)
The conservation between OpPKS8 and these putative BGCs from S
turcica helped to define the boundaries from OpPKS8
Phylogenetic analyses were performed using Maximum-likelihood and Bayesian Inference
and dehydrogenase domains of the fujikurin-like backbone gene of DED pathogens and orthologous sequences exhibited by several fungi
The orthologous sequences were classified according to fungal lifestyle trait
The Bayesian tree is displayed and branch support values (aLRT SH-like supports and Bayesian posterior probability) are associated with nodes
The Bayesian inference ran for 35,000 generations
fujikuroi IMI 58289 harboring the fujikurin and fujikurin-like gene clusters are highlighted in bold
BGCs closely related to the OpPKS8 gene cluster are shaded gray
species that harbor these BGCs closely related to the OpPKS8 gene cluster have a plant-associated trait
the OpPKS8 gene cluster is the only BGC exclusively found in DED pathogens (among the evaluated species)
raising the possibility that HGT events could have shaped the evolution of OpPKS8 orthologs
an ancestor of the Sordariomycetes and Dothideomycetes classes may have contained a fujikurin-like compound gene cluster
which remained in the genome of some species
would have required the loss of constituent genes across several Sordariomycetes and Dothideomycetes species
species from Leotiomycetes (Hymenoscyphus fraxineus
and Phialocephala scopiformis) and Eurotiomycetes (Talaromyces cellulolyticus
and Penicillium griseofulvum) classes also have orthologs
making this vertical descent hypothesis unlikely
several species that possess orthologous genes have a plant-associated lifestyle
leading us to speculate that fujikurin-like SMs allow several fungal species to interact with plants
not only as phytopatogens or endophytes but also in a nematophagous/entomopathogenic or opportunistic manner
Comparative genomics have provided important insights into the evolution of fungal pathogens
Several fungal genomes have been sequenced in recent years
including multiple Ophiostomataceae family members
and the publication of this data enables deep comparisons to highlight putative virulence determinants
in view of a singular characteristic of different pathogenic traits in close family members (e.g.
phytopathogenic and Sporothrix mammalian pathogenic fungi)
enabling the identification of virulence determinants linked with the phytopathogenic trait (i.e.
as the Ophiostomataceae family harbors several phytopathogenic fungi
a putative virulence determinant may be widespread in several species
Secondary metabolites are important virulence determinants for microorganisms. These molecules are produced to circumvent host defenses and ensure the success of these organisms in the environment (Keller, 2015)
We explored the SM potential of DED pathogens and identified three interesting BGCs: OpNRPS1
A mycelium phase is essential for invasion of uninfected xylem vessels and for posterior saprophytic growth within moribund trees
and the products of OpPKS10 may be of significant importance during this growth phase
since this BGC may generate functional transcripts and subsequent proteins which would help to catalyze the biosynthesis of natural products
This genome exhibits an ortholog (obic_04723) for the OpPKS8 backbone gene (65% identity between proteins)
indicating that other phytopathogenic species from the Ophiostoma genus may harbor OpPKS8 orthologs
The SM potential of DED pathogens was meticulously analyzed and yielded insights into aspects of genome organization of BGCs
and their possible role as virulence determinants
and mainly OpPKS8 gene clusters during DED pathogenic infection requires further confirmation using wet lab techniques
our findings are important for future research
Fujikurins and fujikurin-like compounds can play significant roles in fungal-plant interactions in several models
including several economically important phytopathogenic fungi
in addition to presenting horizontally transferred origins
we anticipate that other putative virulence determinants can be found in DED pathogens and Ophiostomaceae family members using comparative genomic approaches
as this family is rich in pathogenic traits
Other relevant genetic characteristics could be explored in both Sporothrix and Ophiostoma genera in addition to genetic singularities that may be important virulence determinants
Conceived and designed the experiments: NS
Contributed reagents/materials/analysis tools: MV
All authors read and approved the final manuscript
This study was supported by grants and fellowships from Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) [Grant: Universal 2014 458160/2014-8]
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) [Grant: Biocomputacional Processo 23038.010041/2013-13]
Fundação de Amparo a Pesquisa do Estado do RS (FAPERGS)
and Fundação de Amparo a Pesquisa do Estado do RJ (FAPERJ)
and is part of the Advanced Network of Computational Biology (RABICÓ)
The publication charges for this article were funded by CAPES (process no
The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest
Patrícia Aline Gröhs Ferrareze and the staff of LNCC for their support
Stefanie Hartmann for kindly providing the O
The Supplementary Material for this article can be found online at: http://journal.frontiersin.org/article/10.3389/fmicb.2017.01063/full#supplementary-material
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Ribeiro de Vasconcelos AT and Schrank A (2017) Genome-Wide Analysis of Secondary Metabolite Gene Clusters in Ophiostoma_ulmi and Ophiostoma novo-ulmi Reveals a Fujikurin-Like Gene Cluster with a Putative Role in Infection
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A recent survey in Germany revealed the wide presence of ‘Candidatus Phytoplasma ulmi’ in native elm stands
Accessions were studied for their genetic variability and phylogenetic relationship based on the conserved groEL and the variable imp gene
While the groEL sequences revealed a high intraspecific homology of more than 99%
the homology of the imp gene dropped to 71% between distantly related sequences
Twenty-nine groEL and 74 imp genotypes were distinguished based on polymorphic sites
Phylogenetic analysis of the groEL gene clustered all ‘Ca
ulmi’ strains and separated them from related phytoplasmas of the 16SrV group
The inferred phylogeny of the imp gene resulted in a different tree topology and separated the ‘Ca
one closely related to the flavescence dorée phytoplasma strain FD-D (16SrV-D)
the other affiliated with the flavescence dorée phytoplasma strains FD-C and FD70 and the alder yellows phytoplasma (16SrV-C)
ulmi’ genotypes from Scots elm trees formed a coherent cluster
while genotypes from European white elms and field elms grouped less strictly
The regional distribution pattern was congruent for some of the groEL and imp genotypes
but a strict linkage for all genotypes was not apparent
phylogenetic linkages and geographical distribution
the phylogenetic relationship and the regional distribution of ‘Ca
ulmi’ accessions with a groEL gene fragment and the imp gene—two markers of different resolving powers adding specific information to survey results published recently by the authors
The selected forward and reverse primers for the groEL- and imp genes amplified fragments of about 880 bp and 675 bp, respectively, from all 288 ‘Ca. P. ulmi’ accessions (Fig. 1). The primers also amplified groEL- and imp fragments from the phytoplasmas alder yellows strain ALY, the ‘Ca. P. ulmi’ strain ULW and the flavescence dorée strain FD70.
Amplification of imp (upper panel) and groEL (lower panel) fragments from ‘Ca. P. ulmi’ accessions. Only examples are shown. Sample names are indicated on the top, including the host plant and Federal State. Ug_h, DNA from a healthy Scots elm accession. The gel was photographed with a VWR Imager 2 System, Software Version 1.5.6.0 (https://de.vwr.com) and cropped with Photoshop CS3 (www.adobe.com)
FD70 (MT638098) and ‘Candidatus Phytoplasma ziziphi’ sequences ranged between 94% and 96.4%
shared a lower sequence homology (95.7% to 96.4%) to all other ‘Ca
ulmi’ sequences and was closer related to the ALY (99.1%) and FD70 (98.6%) sequences
This accession was included in the phylogenetic analysis but not considered as a sensu stricto member of the species ‘Ca
Phytoplasma mali’ groEL sequence was on average 69.7%
The multiple alignment of the 790 bp groEL fragment from the ‘Ca. P. ulmi’ sequences, excluding sequence 4120_Ul_SN, revealed a total of 18 polymorphic sites, of which 12 caused a nonsynonymous substitution (Table 1)
mutations altering the amino acid in a significant number of isolates were only present at positions 18
The remaining non-silent mutations occurred in genotype groups with a low number of isolates
A comparison of the 288 groEL sequences, including accession 4120_Ul_SN, on the basis of complete sequence homology, differentiated 29 genotypes, of which 18 occurred more than once (Table 2)
The genotype groups correlated in most cases with the elm species from which they were isolated
ulmi’ genotype was associated with a different elm species
more than one elm species grew at the sampling location
if fruits were unavailable or leaf shapes difficult to interpret
a misidentification of the elm species cannot be excluded
While the majority of isolates (N = 253) showed a gene length of 465 bases
The imp gene of accession 4120_Ul_SN (MT668488) was shorter by six bases
a feature shared with the phytoplasma strain ALY
ulmi’ imp gene sequences ranged from 71 to 100%
whilst homology to the imp gene of the 16SrV-D group phytoplasma FD-D ranged between 66 and 79%
and homology to the 16SrV-C group sequences of ALY (MT668499)
FD70 (MT6684500) and FD-C ranged between 67 and 71%
Homology to the 16SrV-B subgroup member ‘Ca
ziziphi’ was generally lower with a narrower bandwidth and ranged between 61 and 65%
higher homology with 16SrV-C phytoplasmas (ALY
ulmi’ strains to the distantly related species ‘Ca
Alignment of imp sequences from 4319_Ug_SN (MT668492), 3486_Ug_ST (MT668480), 0371_Ul_BB (MT668429), ULW (MT418908) and the 16SrV-group phytoplasmas ALY (MT668499), FD70 (MT668500) and ‘Ca. P. ziziphi’ (CP025121) with Clustal W. The consensus sequence is given above the alignment, showing bases represented in more than 50% of sequences. Sequence alignments have been performed with Clustal W (www.ebi.ac.uk/clustalw/)
Based on complete sequence identity, 74 genotypes were distinguished among the 288 ‘Ca. P. ulmi’ accessions. Twenty-eight genotypes were represented by more than one sequence (Table 3)
and 46 genotypes were unique and their electropherograms re-assessed when a single nucleotide mismatch defined their group exclusion
like the groEL genotypes according to the elm species from which they originated
The imp genotype I comprised most of the accessions from Scots elm trees
and the gene showed higher conservation compared to the linked groEL genes
which associated the remaining 44 accessions to 14 groEL genotype groups
the strain ULW and FD70 coded for a protein of 154 amino acids (aa)
The imp gene of accession 4120_Ul_SN coded for a protein of 152 aa only
Due to the high sequence heterogeneity between the ‘Ca
homology between distantly related isolates dropped to 48%
A protein-based reassessment of the genotype groups revealed that three sequences
shared identical IMP sequences to others reducing the number of genotypes to 71
Homology to the 16SrV-C group phytoplasmas ALY and FD70 ranged from 42 to 52%
to the 16SrV-D group phytoplasma FD-D from 45 to 61% and decreased below 39% in comparison to the 16SrV-B group phytoplasma ‘Ca
The accession 4120_Ul_SN shared homology of 34%
The ratio between non-synonymous over synonymous mutations was 1.53 (dN = 0.23; dS = 0.15) for imp and 1.00 (dN = 0.01; dS = 0.01) for the groEL-fragment
The ratio of dN/dS > 1 for the imp gene indicates a positive selection
which was not the case for the groEL-fragment
The distribution of the imp genotypes I, II and V largely matched the respective groEL genotype spread (Fig. 5
A greater disparity of distribution was observed between the ‘Ca
ulmi’ imp and groEL genotype groups III and IV
The imp genotype III was absent in East Germany
while the imp genotype IV did not occur in the south of the country
The regional distribution of genotypes was largely congruent with the distribution of the elm species
Genotype groups I and III were mostly associated with Scots elms
genotype II with field elms and genotypes IV and V with European white elms
there was some flexibility in the linkage of groEL- and imp genotypes
was linked to 15 different groEL genotype groups
of which the groEL genotype group I comprised the most with 57 sequences
followed by group III with 16 sequences and group VI with six sequences
The remaining 22 sequences were part of 12 other groEL genotype groups
The same was true when considering the groEL group II in comparison with imp genotype group II
All 26 sequences of the imp genotype group II were part of the corresponding groEL group
but the remaining 35 groEL sequences were associated with a further 19 imp genotype groups
Neither the amplification products nor the electropherograms of the groEL or imp sequences provided evidence that the amplimers consisted of polymorphic fragments
The observed gene combinations were therefore considered as a true linkage and the result of selective evolutionary pressure
and the variable imp gene was chosen to tap the full range of genetic polymorphism of a variable gene
The primer sets for amplifying both genes were deduced from the database entries of the respective genes from the ‘Ca
The oligonucleotides were compared to target genes of close relatives from the 16SrV-B
Due to the high conservation of the groEL gene and the likelihood of an unspecific amplification of other bacterial groEL genes from crude plant extracts
the reverse primer showed six mismatches to the ‘Ca
the only other full-length groEL gene in the 16SrV group published
Primers for the amplification of the imp-pyrG region were fully homologous to the respective sequences of ‘Ca
ulmi’ strain ULW and the flavescence dorée strain FD-C
Both primer sets enabled the amplification of the target fragments from all ‘Ca
the sequencing results revealed no evidence of mixed infection of plants by more than one ‘Ca
but they must have been present in small numbers so alternative base calls were below the threshold line of the electropherogram
A closer examination of this matter would have exceeded the scope of this work
samples were carefully selected based on an even geographical spread and on a representative number of samples from all three elm species
The groEL and imp genotype groups comprised
accessions originating from the same elm species
although parallel genotype groups with the same host species existed
Taking into consideration the many sequences of the larger genotype groups
the distinct host–pathogen strain association seems not to be arbitrary
It is unlikely that the groEL gene product
is responsible for this specificity; however
it is likely that groEL is correlated to one or more such genes specifying this feature
Challenging the attachment of phytoplasmas to host cell membranes in the presence of recombinant AMP or opsonating anti-AMP antibodies reduced the transmission frequency significantly for two vector species
the origin of the high polymorphism remains unclear
One likely notion to explain the host-genotype association might involve monophagous vectors
which specifically transmit the prevailing regional ‘Ca
An occasional presence of this strain in other elm species might be explained by a rare probe feeding of the vector or by root anastomoses
as no vector or vectors have been identified in Germany
The phylogenetic analysis of the groEL fragment placed all
on one root separated from members of the 16SrV-B and C subgroup
The accessions on this root were arranged according to the elm species from which they were isolated
This highly ordered elm species-related grouping broke up when shorter sequences (< 560 bp) were included in the analysis
and although these sequences did not cluster with the ‘Ca
the loss of discriminating characters changed the tree hierarchy
This example demonstrates that although the groEL gene is a proven universal target for phylogenetic analysis
a certain sequence length might be necessary to exploit the full information content of a gene
biologically significant features might be obstructed
resulting in a less meaningful phylogenetic tree
all stamp sequences grouped according to established tuf clusters
Why the immunodominant membrane protein genes of some phytoplasma groups seem to evolve independently from other genes might be explained by their interaction with host proteins
but this does not seem to apply for the imp sequences of the flavescence dorée strains FD-C and FD-D
which differ but share the same plant and insect hosts
Both strains were closely related to alder yellows
to accession 4120_Ul_SN and to a subset of ‘Ca
ulmi’ accessions mainly isolated from European white elm
This situation demonstrates the range of genetic diversity within the 16SrV group and the complex phylogenetic relationship between its members
is more related between otherwise more remote strains highlights its biological importance
a number of polyphagous phloem-feeders such as Allygidius atomarius or Empoasca vitis have been described
but for many Auchenorryhncha species found on elm trees
the host specificity is not completely clear
ulmi’ vectors might provide important new information on how the spatial distribution of ‘Ca
The nucleic acid pellets were resuspended in 200 µl of ddH2O
PCR fragment amplification was carried out in 20 µl reactions
using 20 pmol of forward and reverse primer
10 µl of 2 × primaQuant PCR master mix (Steinbrenner
The amplification was performed in a qTower (Analytik Jena AG
Jena) with the following cycling conditions: three minutes at 95 °C for the initial denaturation and polymerase activation
followed by 35 cycles consisting of 10 s at 95 °C
The final elongation step was set to 5 min at 72 °C
2 µl of the PCR reaction mix were used to verify product yield and size by electrophoresis in a GelRed-stained 2% agarose gel
The PCR fragments of the remaining 18 µl were purified by a PCR purification kit (Qiagen
Hilden) and quantified using a Qubit fluorometer (Thermo Fisher Scientific
Sequencing was performed with the forward and reverse primers used for amplification
Coordinates of individual trees were recorded in WGS84 format and imported to the software program BaseCamp version 4.7.1 (Garmin Ltd
For a graphical display of spatial distribution
groEL- and imp genotypes were depicted as differently coloured dots on maps
GroEL- and imp sequences obtained from the same DNA extract were considered as linked when sequencing electropherograms gave no indication of polymorphic PCR products
it was assumed that primer sets amplified the genes of the prevalent ‘Ca
ulmi’ strain and that both genes were present in single copy
Accession codes: DNA sequences determined in the course of this study have been deposited in GenBank (ncbi.nlm.nih.gov) under accession numbers MT638069 to MT638098 for the groEL fragments and MT668426 to MT668500 for the imp sequences
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Genetic diversity of European phytoplasmas of the 16SrV taxonomic group and proposal of 'Candidatus Phytoplasma rubi’
Genetic relatedness of mycoplasma-like organisms affecting elm
a novel phytoplasma taxon associated with jujube witches’-broom disease
Virus disease of field elm (Ulmus minor Mill.) in Croatia
First Report of ‘Candidatus Phytoplasma ulmi’ in Ulmus laevis in Germany
First report of ‘Candidatus Phytoplasma ulmi’ on elm in Belgium
Widespread occurrence of ‘Candidatus Phytoplasma ulmi’ in elm species in Germany
Identification and characterization of the phytoplasma associated with elm yellows in southern Italy and its relatedness to other phytoplasmas of the elm yellows group
Molecular characterization of elm yellows phytoplasmas in Croatia and their impact on Ulmus spp
Phloem necrosis of elms: symptoms and histopathological observations in tolerant hosts
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Multigene sequence data and genetic diversity among ‘Candidatus Phytoplasma ulmi’ strains infecting Ulmus spp.
Predicting relatedness of bacterial genomes using the chaperonin-60 universal target (cpn60 UT): application to Thermoanaerobacter species
The groEL gene as an additional marker for finer differentiation of ‘Candidatus Phytoplasma asteris’-related strains
Differentiation of ‘Candidatus Phytoplasma cynodontis’ based on 16S rRNA and groEL genes and identification of a new subgroup
The CpnClassiPhyR is a resource for cpn 60 universal target-based classification of phytoplasmas
phylogenetic comparison and serological relationship of the Imp protein of several ‘Candidatus Phytoplasma aurantifolia’ strains
Multilocus sequence analysis reveals the genetic diversity of European fruit tree phytoplasmas and supports the existence of inter-species recombination
Identification of 17 ‘Candidatus Phytoplasma pyri’ genotypes based on the diversity of the imp gene sequence
Evaluation of intraspecies genetic variation within the 60 kDa heat-shock protein gene (groEL) of Bartonella species
Isolation of the gene encoding an immunodominant membrane protein of the apple proliferation phytoplasma
and expression and characterization of the gene product
An immunodominant membrane protein (Imp) of ‘Candidatus Phytoplasma mali’ binds to plant actin
Positive selection acting on a surface membrane protein of the plant-pathogenic phytoplasmas
In vitro expression of phytoplasma immunodominant membrane proteins
In: Phytoplasmas and Phytoplasma Diseases Management: How to Reduce Their Economic Impact
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StAMP encoding the antigenic membrane protein of stolbur phytoplasma is useful for molecular epidemiology
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22026316) was funded by the “Fachagentur Nachwachsende Rohstoffe e.V.” (FNR)
a promotor of the German Federal Ministry for Food and Agriculture
Open Access funding enabled and organized by Projekt DEAL
Max Planck Institute for Plant Breeding Research
Department of Integrative Infection Biology Crops-Livestock
performed all experiments and drafted the manuscript
designed the study and contributed to manuscript preparation
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Microbe and Virus Interactions with Plants
Volume 12 - 2021 | https://doi.org/10.3389/fmicb.2021.699783
The dimorphic fungus Ophiostoma novo-ulmi is the highly aggressive pathogen responsible for the current
Genome and transcriptome analyses of this pathogen previously revealed that a large set of genes expressed during dimorphic transition were also potentially related to plant infection processes
which seem to be regulated by molecular mechanisms different from those described in other dimorphic pathogens
novo-ulmi can be used as a representative species to study the lifestyle of dimorphic pathogenic fungi that are not shared by the “model species” Candida albicans and Ustilago maydis
In order to gain better knowledge of molecular aspects underlying infection process and symptom induction by dimorphic fungi that cause vascular wilt disease
we developed a high-throughput gene deletion protocol for O
The protocol is based on transforming a Δmus52 O
novo-ulmi mutant impaired for non-homologous end joining (NHEJ) as the recipient strain
and transforming this strain with the latest version of OSCAR plasmids
The latter are used for generating deletion constructs containing the toxin-coding Herpes simplex virus thymidine kinase (HSVtk) gene which prevents ectopic integration of the T-DNA in Ophiostoma DNA
The frequency of gene deletion by homologous recombination (HR) at the ade1 locus associated with purine nucleotide biosynthesis was up to 77.8% in the Δmus52 mutant compared to 2% in the wild-type (WT)
To validate the high efficiency of our deletion gene methodology we deleted ade7
which also belongs to the purine nucleotide pathway
and opf2 which encode fungal binuclear transcription factors (TFs)
The frequency of gene replacement by HR for these genes reached up to 94%
We expect that our methodology combining the use of NHEJ deficient strains and OSCAR plasmids will function with similar high efficiencies for other O
novo-ulmi genes and other filamentous fungi
these works suggest that dimorphic growth could be closely related to DED infection development
but regulated by other molecular mechanisms in Ophiostoma species
which offers a new perspective for understanding the relationship between pathogenesis
novo-ulmi did not show any alteration in vegetative development and pathogenicity
while showing increased gene replacement by HR at the ppo1 locus encoding a putative cyclooxygenase
In spite of enhancement of HR events in NHEJ-defective strains
extensive screening is still required to ensure replacement at the desired locus
This step is overall quite laborious and time-consuming
and thus limits systematic gene disruption and genomic functional analysis
A high efficiency deletion gene protocol based on HR also requires a high-throughput approach to generate deletion constructs and simplify the identification of deletion mutants upon fungal transformation
we used the OSCAR-based counterselection system in combination with a Δmus52 mutant defective in NHEJ to develop an efficient strategy for systematic gene deletion in the highly aggressive DED fungus O
Although these two methods can be used separately
the NHEJ mutant exhibited a significant increase in the frequency of HR [over 75% compared to 2% in wild-type (WT)] when using the counterselection marker approach
We first targeted genes ade1 and ade7 since their deletion resulted in the production of characteristic pink mutants on non-selective (rich) media
thereby facilitating the phenotypic identification of knockout mutants
we validated our strategy by successfully deleting genes bct2
and opf2 which encode TFs belonging to the Zn(II)2Cys6 family
These new efficient tools for targeted gene deletion
together with existing resources for the study and manipulation of DED fungi
open the way to a new level of functional analysis and understanding the relationship between morphogenesis and pathogenesis in vascular tree pathogens
yeast cells of each parental strain were harvested by filtration through one layer of Miracloth (Calbiochem
#475855) and centrifugation at 5500 g for 10 min
Yeast cells were then suspended in sterile distilled water to a final concentration of 5 × 107 cells/mL
Transformants expressing either of the hygromycin B phosphotransferase (hph) or nourseothricin acetyltransferase (nat1) resistance genes were cultivated on 2PDA supplemented with 300 μg/L hygromycin B (hygromycin
#10687010) or 50 μg/L nourseothricin dihydrogen sulfate (nourseothricin
To counterselect transformants expressing HSVtk
50 μg/L 5FU (Thermo Fisher Scientific
The ccdB SurvivalTM 2 T1R Escherichia coli strain (Thermo Fisher Scientific, #A10460) was used to propagate the vector pOSCAR-HSVtk (Sarmiento-Villamil et al., 2020)
which harbors the ccdB gene lethal for most E
coli One shot® OmniMAXTM 2 T1R competent cells (Thermo Fisher Scientific
#C854003) were used to produce the deletion construct
coli strain DH5α (Bethesda Research Laboratories
coli strains were grown in or on Luria Bertani (LB) media containing 100 μg/mL ampicillin sodium salt (ampicillin
#A9518) or 100 μg/mL spectinomycin dihydrochloride pentahydrate (spectinomycin
Fungal parental strains were transformed with A
tumefaciens which was grown on LB or in minimal medium (MM) supplemented with 50 μg/mL spectinomycin
PCRs were performed according to the manufacturer’s recommendations in a total volume of 50 μL and under the following PCR cycling conditions: an initial denaturation of 1 min at 94°C
and completed with a final extension of 5 min at 68°C
All PCR products were gel-purified using EZ-10 spin column DNA gel extraction miniprep kit (Bio Basic
#BS367) according to the manufacturer’s instructions
a 5 μL BP clonase reaction was set up to include 1 μL BP clonase II enzyme mix (Thermo Fisher Scientific
95 ng of pOSCAR-HSVtk and 100 ng of pA-Hyg-GFP-OSCAR or 60 ng of marker vector pA-NTC-OSCAR
The BP reaction was incubated at 25°C for 20 h in a PCR thermocycler
the reaction mixture was used to transform One Shot OmniMAXTM 2 T1R Chemically Competent E
coli according to the manufacturer’s recommendations
Bacterial colonies were recovered on LB plates supplemented with 100 μg/mL spectinomycin following overnight incubation at 37°C
Correct structure of each deletion construct was verified by restriction enzyme digestion
Constructs pade1_hyg_1kb and pade1_hyg_2kb were developed using pA-Hyg-GFP-OSCAR
Agrobacterium tumefaciens strain GV3101:pMP90 (Koncz and Schell, 1986) was used for transferring T-DNA harboring dual molecular selection markers
The deletion constructs were transformed into A
tumefaciens strain GV3101:pMP90 using the heat shock method
spread onto LB plates supplemented with 100 μg/mL spectinomycin and incubated at 25°C for 2 days
For A. tumefaciens-Mediated Transformation (ATMT) of O. novo-ulmi, the method described by Mullins et al. (2001) was used with some variations
tumefaciens strains containing a deletion construct were grown at 28°C for 2 days in MM supplemented with 100 μg/mL spectinomycin
tumefaciens cultures were diluted to optical density (OD600) of 0.2 in 6 mL induction medium (IM)
which contained MM supplemented with 0.5% (W/V) glycerol
40 mM 2-(N-morpholino) ethanesulfonic acid (MES
#M5287) at pH 5.3 and 100 μg/mL spectinomycin
Bacterial cells were grown for an additional length of time until the OD600 value reached 0.6–0.9
tumefaciens culture and 100 μL of a yeast cell suspension (5 × 108 cells/mL) from each fungal parental strain were mixed and spread on a sterile 0.45 μm pore nitrocellulose membrane (Sartorius Stedim Biotech GmbH
#1140647ACN) overlaid on top of 20 mL of co-culture medium plate
which contained IM plus 200 μM 3′,5′-dimethoxy-3′hydroxyacetophenone acetosyringone (AS
Following incubation at 25°C for 2 days
the filters were cut in strips and transferred to selection medium
which contained 2PDA supplemented with 300 μg/mL hygromycin or 50 μg/L nourseothricin to select the transformants
with or without 50 μg/mL 5FU as a counterselecting agent of ectopic transformants and 100 μg/mL cefotaxime sodium salt (cefotaxime
#C7039) and 100 μg/L moxalactam sodium salt (Sigma-Aldrich
single colonies began to appear on the selection medium
Three independent ATMTs of each parental fungal strain were performed with each combination of A
Phenotype analysis based on the recovery of pink colonies from individual transformants was used for distinguishing visually Ade– from Ade+ survivors. To confirm gene replacement, randomly selected pink colonies were analyzed by PCR with primer combinations ade1F_809 and ade1R_1221, and ade7F_368 and ade7R_809 (Supplementary Table 1)
which amplified roughly 441 and 594 bp of ade1 and ade7
The HR frequencies for each gene in each strain
treatment and replicate experiment were estimated by the pink/white transformant colony ratio and analyzed by the application of generalized linear models (GzLMs) using Logit as the link function and Binomial as the underlying distribution
An additional analysis to obtain orthogonal contrasts was also conducted among treatments with Bonferroni adjustments to the p-values
americana saplings was analyzed by application of GzLMs using identity as the link function and Gaussian as the underlying distribution
Orthogonal contrasts among the treatment medians with Bonferroni adjustments to the p-values were also performed
All statistical analyses were conducted using Lme4
and emmeans packages under R environment (R Project software
Each PCR resulted in three fragments of roughly 1.9 Kb of the entire HVStk cassette
1.1 Kb of the HVStk promoter proximal to the left border of the T-DNA
and 0.3 Kb of the HVStk terminator (data not shown)
Eight transformants had truncations of their HVStk cassettes while two transformants had intact HSVtk cassettes (data not shown)
Effect of ade1 deletion on colony morphology of Ophiostoma novo-ulmi after 7 days incubation on potato dextrose agar (PDA) at 21°C
The plate on the left is the parental strain
and the plate on the right is a Δade1 mutant
HR frequency was significantly higher in transformants obtained with construction containing 2 Kb of flanking homologous region
thereby showing a correlation between the length of homologous region and the efficiency of homologous integration
Bar graphs showing the effects of using 1 Kb or 2 Kb of homologous sequence flanking targeted loci
and applying counterselection with 5-Fluoro-2′-deoxyuridine
on the frequency of homologous recombination (HR) in Ophiostoma novo-ulmi strain 174_68Δmus52
Standard error bars are displayed at the top of each bar
Different letters above each bar indicate statistically significant differences (p < 0.05) according to the sequential Bonferroni method for error correction
There was no statistically significant difference between both HR rates
comparison of HR rates between transformants isolated from supplemented (5FU) versus non-supplemented medium revealed a statistically significant difference caused by a three-fold increase in the number of gene replacement mutants
as well as a stark reduction (94%) in the number of ectopic transformants in the presence of 5FU
This result showed that HSVtk worked well in preventing random integration of the deletion construct T-DNA in the NHEJ-impaired mutant of O
thus greatly simplifying the selection of null mutants
These slight variations in HR frequencies between ade1 and ade7 may be closely related to locus-specific properties
including differences in chromatin structure
Recovery data for ade7 mutants also corroborated the effect of 5FU in enrichment of gene replacement mutants as well as in decreasing the number of ectopic transformants
Gel images showing PCR confirmation of ade1 or ade7 deletion in Ophiostoma novo-ulmi transformants
(A) Total genomic DNA samples from twelve pink colony transformants and one white colony transformant (t13) were amplified with ade1 specific primer pair ade1F-809 and ade1R-1221 (top panel) and nat1 marker primers ntcF_562 and ntc_975_R (bottom panel)
1 kb plus (FroggaBio); t1 through t6 and t7 through 13
174_68Δmus52 transformants obtained using pade1_NCT_2kb and pade1_NTC_1kb
(B) Total genomic DNA samples from twelve pink colony transformants and one white colony transformant (t26) were amplified with ade7 specific primer pair ade7F-368 and ade7R-809 (top panel) and nat1 marker primers ntcF_562 and ntc_975_R (bottom panel)
1kb plus (FroggaBio); t14 through t19 and t20 through 26
174_68Δmus52 transformants obtained using pade7_NTC_2kb and pade1_NTC_1kb
Disease severity of Ulmus americana saplings inoculated with Ophiostoma novo-ulmi H327 wild-type
NHEJ-defective mutant strain 174_68Δmus52
and two adenine auxotrophs (ade1-6 and ade7-13) derived from it by targeted deletion of genes ade1 and ade7
novo-ulmi strain 174_68Δmus52 transformed with OSCAR constructs containing 1 Kb of homologous arm length for genes encoding fungal binuclear TFs bct2
ogf1 and opf2 (located on chromosomes 1 or 2) were grown on selection medium with nourseothricin and 5FU
PCR analysis of 17 transformants from each fungal transformation confirmed deletion of bct2
These results confirmed that null mutants could be recovered at high frequency in O
novo-ulmi through an approach combining OSCAR-based counterselection with a Δmus52 mutant defective in NHEJ
In order to fully exploit the new knowledge obtained from NGS approaches and gain insight into molecular aspects underlying infection process and symptom induction by DED pathogens
we developed a high-efficiency gene deletion methodology by HR for O
Truncation of T-DNA could therefore explain why counterselection by HSVtk failed in WT O
Our results confirmed that NHEJ plays a major role in HR and that efficacy depends on the length of homologous arms that flank the gene targeted for deletion
in spite of the significant increase in HR frequency resulting from mus52 deletion in O
a high rate of random integration of the T-DNA still occurred in strain 174_68Δmus52
thereby suggesting the preferential use of the NHEJ over the HR pathway in O
we suspected that counterselection by HSVtk could work in O
A comparison of 174_68Δmus52 ectopic transformants recovered from selective medium
showed a drastic reduction (up to 94%) of transformants in the presence of 5FU
These results suggest that Ku80 intervenes in the deletion of foreign DNA segments during the genomic integration process
coupling of ATMT with HSVtk-based counterselection worked efficiently for enrichment of gene replacement mutants and prevention of ectopic transformants in strain 174_68Δmus52
successful targeted deletion of five genes
suggests that the ATMT-OSCAR-HSVtk strategy is not restricted to certain loci
The virulence of knockout mutants for genes bct2
ogf1 and opf2 will be evaluated when elm saplings are available for pathogenicity tests
novo-ulmi was limited by the absence of an efficient gene deletion tool
as we were able to recover from 64 to 94% of targeted deletion mutants among transformants derived from NHEJ-defective strain 174_68Δmus52 subjected to a dual-selection system in OSCAR
systematic gene function studies can now be envisioned for elucidating the molecular bases of pathogenicity and virulence in the DED fungi
The original contributions presented in the study are included in the article/Supplementary Material
further inquiries can be directed to the corresponding authors
ESN constructed the Ophiostoma novo-ulmi strain 174_68Δmus52 used in the improved OSCAR-based protocol
JLS-V and TCO constructed the gene delete OSCAR plasmids and performed transformation experiments
LB carried out the inoculations on elm saplings and supervised the research
JLS-V wrote the manuscript with input from all authors
All authors contributed to the article and approved the submitted version
Genome British Columbia and Génome Québec within the framework of project bioSAFE (Biosurveillance of Alien Forest Enemies; project number 10106)
and Philippe Silar at the Université Paris-Diderot for their help in producing Ophiostoma novo-ulmi strain 174_68Δmus52 impaired for Non-Homologous End Joining
André Gagné and Jean-Guy Catford and Camille Bédard at the Université Laval for technical assistance
María Dolores García Pedrajas at Instituto de Hortofruticultura Subtropical y Mediterránea La Mayora (IHSM La Mayora-CSIC-UMA) for providing OSCAR plasmids
and Philippe Tanguay at the Natural Resources Canada for supplying A
The Supplementary Material for this article can be found online at: https://www.frontiersin.org/articles/10.3389/fmicb.2021.699783/full#supplementary-material
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Copyright © 2021 Sarmiento-Villamil, de Oliveira, Naruzawa and Bernier. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY)
provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited
*Correspondence: Jorge Luis Sarmiento-Villamil, anNhcm1pZW50b0BlZWxtLmNzaWMuZXM=
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will make a Greenfield type investment to Romania for the construction of a factory that will produce washing machines in Ulmi
Dambovita County.The new washing machine factory will be the company’s first production unit to integrate 4.0 standards
The factory will introduce Cyber Physical Systems
fleet and inter-connected network) and analysis systems
The total value of the project investment announced in Dambovita county totals RON 471 million
will invest EUR 70 million from the company’s profit in the past years to build the new factory
Arctic transforms Romania into a production hub for Europe
investments in Romania have always been important
and this new investment will allow us to transform Romania into a production hub for the whole Europe,” Arçelik CEO Hakan Bulgurlu said
our project will create 480 work places in Dambovita County
in a region with the highest unemployment in Romania
this investment will contribute to improving the quality of life at a local level
through the professional development of the work force
but also by attracting new investors in the area,” Nihat Bayiz
“The new factory will integrate up-to-date technologies, as well as the wireless communication of production lines with those in another countries that are part of the Arçelik group, but also smart tools,” Nihai Bayiz said.
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the leader of the Romanian home appliance market and one of the main contributors to the local economy
marks a milestone of one million washing machines produced at its Ulmi manufacturing plant in Dambovita county
the first Industry 4.0 factory in Romania and one of the most modern production facilities in Europe
The one million Arctic washing machines were produced with minimal impact on the environment
Thanks to technologies based on Industry 4.0 principles
the energy consumption per unit of product has decreased by 28%
the factory is partly powered by renewable energy
the photovoltaic system having produced over 1.7 million kWh so far
thus reducing carbon dioxide emission by around 600 tons
The water used during the production process is also almost 100% recycled and reused. Owing to its advanced wastewater treatment and rainwater collection systems, 26.000 cubic meters of water have been recycled and reused – the equivalent of 10 Olympic pools.
The Ulmi unit received an impressive number of accreditations for being a green factory
and it is the only one in Romania certified as LEED Platinum
This certification acknowledges its sustainable production performance
In Romania Arctic also owns and operates the largest household appliance manufacturing factory in continental Europe, the Gaesti unit having produced so far over 38 million refrigerators which have been exported to more than 70 countries.
Turkish group Arcelik will hire 4,000 people at its new factory in Ulmi
The group will invest around EUR 200 million in the factory
The factory will be built on a plot of land of 70 hectares
which was purchased by the company from a local
Ulmi has a population of around 4,000 inhabitants
According to Oprea, the company hopes to start production 10 months after receiving the building permit. “For me, as county authority, is an extremely important moment and we welcome the initiative of the Arcelik group to make this factory in Dambovita county,” Oprea told Mediafax
the leader of the Romanian home appliances market and one of the main contributors to the local economy
marks the production of 1,000,000 washing machines at the factory in Ulmi
the first factory in Romania operating according to the principles of Industry 4.0 and one of the the most modern production facilities in Europe
following a total investment of 153 million euros
the Arctic factory in Ulmi integrates the latest machine learning technologies and automation processes
which allow employees to work side by side with robots
generating an increase of productivity by up to 30%
More than 200 robots were involved in the production process of the one million washing machines
the production center in Ulmi incorporates automatic systems for handling and storage of components
which are transported from the warehouse to the assembly line with the help of autonomous machines
Over 70% of production operations are based on self-determined and self-managed systems
more than 407,000 hours of testing have been conducted in the Research and Development departments
Arctic also owns and operates in Romania the largest household appliances factory in Continental Europe
the place where over 38 million refrigerators have been produced so far
which have been exported to over 70 countries
the leader in Romania’s home appliance market
has reached a significant milestone by producing its four millionth washing machine at the Ulmi factory
Romania’s first Industry 4.0 unit and one of the few in Europe certified by the World Economic Forum (WEF) as a Sustainability Lighthouse
acknowledging its outstanding sustainability performance
the factory stands as a benchmark facility for energy efficiency
equipped with cutting-edge automation and machine learning technologies
the factory’s two production lines have the capability to produce 407 models of washing machines
destined to both domestic and international markets
82 percent of Ulmi’s production is destined towards exports
Appliances reach consumers in 42 countries
yet over 94 percent of total exports are destined for European markets
”The inauguration of our Ulmi facility in 2019 marked a significant leap into the next generation of manufacturing
aligning with the principles of Industry 4.0 positioning us as a benchmark in terms of energy efficiency
The production of the four-millionth washing machine is the result of a collective effort of the entire team
We focused all our energy on finding the best solutions
so that each product that goes out of the factory leaves the smallest possible carbon footprint
Arctic is not just a company that manufactures appliances
but also one that focuses on a greener future for us and the generations to come
Finding a balance between sustainability and efficiency is a proof that excellence in production can be achieved
keeping in our hearts the care for the environment
and we intend to surpass the milestone of 5 million units produced at Ulmi by the end of the year.”
Benefitting from advanced technologies based on Industry 4.0 concepts
over 80 percent of the factory’s logistic processes are automated
due to the high level of technological integration at the production points
the facility records significant improvements in traceability capacity
ensuring a high standardization of quality
are involved in the production of washing machines
leading to a 30 percent increase in productivity
resource consumption within the appliance manufacturing process at the Ulmi facility has witnessed a significant decline since its opening
with a 56 percent reduction in energy usage
a 60 percent decrease in water consumption
and a 26 percent decrease in production waste
The facility utilizes energy from renewable sources
with 20 percent being generated through the owned photovoltaic park
at least half of the total energy used in the production of the 4 million washing machines originated from suppliers with certified origin
in the manufacturing process of these appliances
and nearly 5 tons of fishing net threads were utilized
Metal and plastic materials are the primary elements required in appliance production
has set out to increase the proportion of recycled plastic to 40 percent and the content of biomass-based materials to 5 percent by 2030
have come out to explain reasons behind the recently sponsored soccer tournament and honouring of deserving teachers in Uromi
Explaining in details to Daily Independent
Executive Chairman of the Uromi Like Minds Initiative
Sylvester Abumere Ekpen said that the gesture was to help people loosen up while also encouraging scholarship and hard work
ULMI had previously sponsored scholarship schemes for students of Uromi descent in from Edo State
Made up principally of high flying successful sons and daughter of Uromi nation
the group has become a strong organisation promoting well being of indigens from the town in wherever they find themselves
Ekpan said: “all work and no play makes Jack a dull boy
“We understand that for all-round development of the mind and body
a mix of academic and social activities are required.”
The soccer tournament was amongst Secondary Schools and also featured honoring deserving school teachers who had distinguished themselves within the last twenty-five years and still counting
between Ebhoiyi and Obeidu secondary schools which began at 1.15 pm
in the main bowl of the LGA Council Sports arena
Ebhoiyi defeated Obeidu Secondary School 4-3 in a penalty shootout after the normal time scores were one apiece
The goals were scored by Ikekhwa Dennis and Okoduwa George of Ebhoiyi and Obeidu secondary schools respectively
The final proper saw a popular private school in Uromi
pip the star-studded Agba grammar school to take home the inaugural gold cup against all odds
The game was watched by many sons and daughters of Uromi who went to the commercial town for the yuletide celebration
A first-half goal scored by Iyoha Friday of Buddie Group of Schools was all that made the difference between the school and Agba Grammar School
Azeez Ugbodaga of BGS won the Tournament`s MVP award
The top scorers’ award went to Iyoha Godspower of Ebhoiyi secondary school with 4 goals
while Ugbodaga Miracle of BGS was crowned the best goalkeeper of the championship
The highpoint of the fiesta was the awards of excellence given to about nine teachers who have served for about twenty-five years
the group appreciated the teachers for their selfless services to the students and community at large and promised that the association would make it an annual event in Uromi
“We have recently considered and passed a budget for 2022 that is almost twice the 2021 budget
While that shows commitment on the part of existing members
who shares a similar vision with the Association
to team up and join hands with ULMI,” Ekpan said
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TV Independent on YouTube and IndependentNgr (Facebook
Uromi Like Minds Initiative (ULMI) with members home and abroad
has commenced the renovation of the Edo State Library situated in Uromi
the administrative headquarters of Esan North-East Local Government Area of the state
in a telephone conversation with selected journalists from the UK
said that the project is part of its corporate social responsibility
The group has in the last two years since its establishment been involved in some community and human capacity development projects
it supplied some orphanage and old people’s homes relief materials and food items to celebrate the season
While speaking to newsmen on the matter recently
Chairman of welfare committee and Vice Chairman of the organisation
Sebastine Osita described the library project as the biggest project the organisation has embarked on since its formation two years ago and harped on the need for students in the community to rekindle their interest in learning
“ This particular project is dear to my heart because in my earlier years in the town I had the privilege of visiting the library to study and having unrestricted access to various textbooks
“The serenity of the library provided a perfect environment for study
It was also a place to meet and share ideas with students from other schools
“Having enjoyed all these privileges in the past
it was heartwarming when we as a group decided to take on the effort to revive the library”
our strategy is to first provide a modern library with ICT facilities and then follow with an awareness campaign aimed at encouraging full utilization,” Osita said
Picking the Uromi library was not a difficult decision to take according to the ULMI vice-chairman
we met towards the end of the year to select projects/programs that will be executed in the following year once approved by the Exco team
and blessed by the entire members at the General Meeting
the executive chairman of the organisation which has its members across the globe
recalled how the state-owned library had in the past been a source for learning and getting academic material and harped on the need to bring back the past glory of the institution through this renovation works and equipping it with books
The renovation work on the building has cost ULMI N4.6m
which is being handled by an indigenous firm
Melvin Global LTD and the completion is estimated to be within five weeks
according to Prince Kenneth Edenojie who is the association`s director of Projects
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the administrative headquarters of Esnortheastast LGA of Edo State will come alive with the Second Edition of the Uromi Like Minds Initiative Football Competition as it enters the Finals on Monday
The games will see Agba Grammar school Uromi lock horns with Arue Secondary School both from Uromi by 3 pm
The competition which began in October with about 20 Schools participating is expected to welcome dignitaries from Uromi and Esan land both at home and in the diaspora
the third-place match would be played between Ulinlin Secondary School
an NGO made up of sons and friends of Uromi at home and in the diaspora has been engaging in a secondary schools football competition in ENE LGA since 2021 and this is the second edition
the Director of Projects and member of the organizing committee
Prince Ken Edenojie express readiness to host a beautiful final as he said that everything is already in place to have a successful final
the 26th and the people of Uromi are ready to treat themselves to an exciting moment on Sunday”
we have made adequate preparations to ensure that we have a memorable final with the young boys who are already looking up to the games,” he said
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