Related Genomes Research Articles

Genomic characterization and evolutionary analysis of a Getah virus variant from piglets in central China

IntroductionAs a re-emerging mosquito-borne virus, Getah virus (GETV) has been found in more than 10 countries surrounded by the Pacific Ocean and shows a broadly host tropism, raising concerns for the potential risk to public health. Horses and pigs are susceptible to GETV and play pivotal roles to the GETV adaptive evolution.MethodsHere, we reported a GETV outbreak in a pig farm with 20% suckling piglets losses. The genomic characteristics and evolutionary relationship of the pathogenic viral strain were also analyzed.ResultsThe isolate GETV-HeN202309 shared the highest nucleotide identity of 99.8% with strains from Guangdong and Sichuan province, suggesting it is an imported transmission. Although the phylogenetic analysis divided GETV into four groups (groups I–IV), only strains in group III were dominant and widely circulating in the fields. Furthermore, several amino acid substitutions in E2 protein were identified among different GETV groups and the substitution at D262th N site led to an additional glycosylation modification. Besides, six amino acid sites were under positive selection of E2 protein. Most of these special sites were distributed in domain A, B, and C of E2 protein, which are usually associated with the GETV infection and immune response.DiscussionOur study expands knowledge of GETV pathogenicity and deepens understanding of GETV genetic and adaptive evolution, which would be valuable for the development of diagnosis and prevention for GETV.

Complete chloroplast genomes of 13 species of the Impatiens genus for genomic features and phylogenetic relationships studies

Impatiens spp. are well-known ornamental and medicinal plants that are widely distributed in the highlands and mountains of southwestern China. This area is one of the hotspots for the distribution of Impatiens species, with typical karst landforms and abundant wild resources. Many of these species are endemic to a narrow distribution area, but their classification and relationships are relatively unclear because of insufficient field investigations, diverse morphological characteristics and lack of molecular information. In this study, chloroplast genome analysis of 13 species (including 2 synonyms) in karst habitats was conducted to study their characteristics and phylogenetic relationships. The results revealed that these chloroplast genomes all had double-stranded tetrad structures ranging in length from 151,284 bp to 152,421 bp, including a total of 113 genes, including 80 protein-coding genes, 29 transfer RNAs, and 4 ribosomal RNAs. SSRs mainly consist of A/T repeats and AT/AT repeats, while INEs mainly consist of positive repeats and palindromic repeats. The frequency of codon usage was essentially the same, with a total of 31 high-frequency codons detected, the vast majority ending in A/U. Five mutation hotspots were detected: rps16-trnQ-UUG, ndhF, ccsA-ndhD, ycf1, and trnN-GUU, among which ycf1 had the highest Pi value and the greatest potential as a DNA barcode marker. Our phylogenetic tree shows that all 13 species belong to Section Impatiens. And supported the classification of I. reptans and I. rhombifolia should as synonyms (BS = 100/PP = 1.00). This study comprehensively analyzed the cp genomes of different taxa, sheds light on the taxonomic intricacies of Impatiens species, provide valuable information into its phylogenetic and taxonomy.

Citrus genomes: Past, present and future

Abstract Over the past decade, genome sequencing, and assembly approaches have been greatly improved resulting in the assembly of many genomes for citrus including wild, domesticated and citrus related genomes. Improvements in technologies have led to assembled genomes with higher completeness, contiguity, quality and accuracy that have greatly facilitated annotation and analysis. This review summarizes the evolution of the sequencing, assembly and annotation technologies leading to citrus genomes over the past 11 years, a comprehensive evaluation of their quality, contiguity, and completeness, and their major findings and applications. Of the 50 genomes now available, 35 have been assembled to chromosome level, 15 to draft level, and 14 were haplotype-resolved assemblies. To date there have been four pangenome wide studies for citrus. The very recent genomes assembled with long read sequencing have achieved more than 99% and more than 98% assembly and annotation completeness (BUSCO) respectively. However, some early genomes are not of the same high quality as more recently sequenced genomes and would benefit from re-sequencing. A more comprehensive pan genome based upon of a larger set of species and genotypes at assembled at the haplotype level would allow genomics to deliver the maximum benefits for citrus improvement and research.

Short communication: Genomic prediction based on unbiased estimation of the genomic relationship matrix in pigs.

The traditional genomic relationship matrix (GRM) has shown to be a biased estimation of true kinship, which can affect subsequent genetic analyses. In this study, we employed an unbiased kinship (UKin) estimation method within the genomic best linear unbiased prediction framework to evaluate its prediction performance on both a simulated dataset and a Large White pig dataset. The simulated dataset encompasses six traits, 900 quantitative trait loci, and 36000 single nucleotide polymorphisms (SNPs). Two scenarios (small effect genes; major genes and small effect genes) and three heritabilities (0.1, 0.3 and 0.5) were considered. The Large White pig dataset includes two traits, 3290 animals and 35172 SNPs. The prediction performance of the Ukin method was compared with several other GRM construction methods, including VanRaden1 and 2 methods, Goudet method, and the runs of homozygosity (ROH) method. In the simulated dataset, VanRaden2 method and the UKin+VanRaden1 method achieved relatively higher prediction accuracies, averaging 0.561 and 0.558 for the six traits, respectively. Apart from the ROH method, all methods demonstrated similar levels of unbiasedness, around 1.10. In the Large White pig dataset, the accuracy of two traits hovered around 0.780, and the unbiasedness around 0.99, again with the ROH method as an exception. This study underscores the potential of the unbiased kinship estimation method in animal breeding.

The repetitive DNA landscape in the 'brizantha' agamic complex of Urochloa P. Beauv.

Urochloa P. Beauv. (formerly classified as Brachiaria (Trin.) Griseb.) is a genus of African perennial grasses that is extensively cultivated in tropical countries for cattle nutrition. Three of the most economically relevant species, Urochloa brizantha, U. decumbens, and U. ruziziensis, form the 'brizantha' agamic complex, which includes allopolyploid series with distinct subgenomes. Investigating the composition and organization of repetitive DNA, a major component of grass genomes, can provide insights into their genomic relationships and evolutionary history. This study aimed to characterize the repetitive DNA landscape of selected Urochloa species belonging to the 'brizantha' agamic complex; identify and compare major repeat classes across species and evaluate their potential as cytogenetic markers on mitotic chromosomes using fluorescent in situ hybridization (FISH). Clustering analysis revealed that repetitive DNA constitutes 56-65% of the genomes, with Ty3/Gypsy retrotransposons, particularly the Athila and Retand lineages, representing the most abundant repeat class. U. decumbens exhibited the highest proportion of Ty3/Gypsy retrotransposons, while U. ruziziensis had the highest satellite DNA content. The chromosomal location of representative satellites (UroSat-1a, UroSat-2a, and UroSat-3) was determined in all three species via FISH. UroSat-1a was detected in all centromeres, while UroSat-2a and UroSat-3 signals varied in number and position. Our findings validate the use of satDNA as cytogenetic markers in the Urochloa 'brizantha' agamic complex and revealed genomic relationships among different species and ploidy levels.

Exploration of the genetic landscape of bacterial dsDNA viruses reveals an ANI gap amid extensive mosaicism.

Average nucleotide identity (ANI) is a widely used metric to estimate genetic relatedness, especially in microbial species delineation. While ANI calculation has been well optimized for bacteria and closely related viral genomes, accurate estimation of ANI below 80%, particularly in large reference data sets, has been challenging due to a lack of accurate and scalable methods. To bridge this gap, we introduce MANIAC, an efficient computational pipeline optimized for estimating ANI and alignment fraction (AF) in viral genomes with divergence around ANI of 70%. Using a rigorous simulation framework, we demonstrate MANIAC's accuracy and scalability compared to existing approaches, even to data sets of hundreds of thousands of viral genomes. Applying MANIAC to a curated data set of complete bacterial dsDNA viruses revealed a multimodal ANI distribution, with a distinct gap around 80%, akin to the bacterial ANI gap (~90%) but shifted, likely due to viral-specific evolutionary processes such as recombination dynamics and mosaicism. We then evaluated ANI and AF as predictors of genus-level taxonomy using a logistic regression model. We found that this model has strong predictive power (PR-AUC = 0.981), but that it works much better for virulent (PR-AUC = 0.997) than temperate (PR-AUC = 0.847) bacterial viruses. This highlights the complexity of taxonomic classification in temperate phages, known for their extensive mosaicism, and cautions against over-reliance on ANI in such cases. MANIAC can be accessed at https://github.com/bioinf-mcb/MANIAC.IMPORTANCEWe introduce a novel computational pipeline called MANIAC, designed to accurately assess average nucleotide identity (ANI) and alignment fraction (AF) between diverse viral genomes, scalable to data sets of over 100k genomes. Using computer simulations and real data analyses, we show that MANIAC could accurately estimate genetic relatedness between pairs of viral genomes of around 60%-70% ANI. We applied MANIAC to investigate the question of ANI discontinuity in bacterial dsDNA viruses, finding evidence for an ANI gap, akin to the one seen in bacteria but around ANI of 80%. We then assessed the ability of ANI and AF to predict taxonomic genus boundaries, finding its strong predictive power in virulent, but not in temperate phages. Our results suggest that bacterial dsDNA viruses may exhibit an ANI threshold (on average around 80%) above which recombination helps maintain population cohesiveness, as previously argued in bacteria.

100. Genomic epidemiology of carbapenemase-producing Enterobacter species in Toronto, Canada, 2007-2021

Abstract Background Identification of transmission networks of carbapenemase-producing organisms (CPO) is critical to identifying their reservoirs and limiting their spread. This study aimed to use whole-genome sequencing to identify genomic relationships between CP Enterobacter (CP-Ent) in Ontario, Canada over a 15-year period. Methods All CP-Ent cases identified by prospective population-based surveillance in the Toronto/Peel Region from first isolate in 2007 to 2021, from hospital sinks (2016-2019), and wastewater treatment plants and surface water sites (2015-2017) were included. CPO isolates were identified by phenotypic screening (ertapenem MIC > 1mg/L or meropenem disc diffusion diameter ≤ 25mm), confirmed as Enterobacter by MALDI-TOF MS and as positive for carbapenemase genes by PCR, and sequenced by Illumina. Genomics analysis utilized a custom pipeline combining Snippy, IQ-Tree, and ClonalFrameML. Results Overall, 182 isolates from 127 patients, 61 isolates from 40 sinks, and 155 isolates from 9 wastewater plants/surface water sites were available (Table 1). Thirty-one of 127 (24%) patients had > 1 sequenced isolate: in 29 patients all isolates were highly related (median SNV distance 3.5, range 0-13); one patient had two CP-Ent species ∼1.5 years apart, and one had 2 sequence types (STs) 86 days apart. Of 12 (30%) sinks with > 1 isolate, 5 had 2 STs recovered at different times (4 with different carbapenemases). Multiple species, STs, and carbapenemases were recovered from sewage trunks and surface water. Using a ≤ 20 SNV threshold between any one pair of isolates, 14 multi-patient putative clusters involving 39 patients were identified; 1 added cluster was identified and 4 expanded when the threshold was increased to 40 SNVs (Table 2). At the 40 SNV threshold, the median number of patients per cluster was 2 (range 2-9), and the median number of hospitals with at least one first identified patient in each cluster was 1.5 (range 1-4). In total, 35% (45/127) patients were part of a cluster. Conclusion CP-Ent in Ontario are diverse, but a significant minority of affected patients are part of genomically-defined clusters. Genomic clusters may reflect undetected transmission of CP-Ent in healthcare, exposure to water, or other as yet unidentified sources. Disclosures Allison McGeer, MD, AstraZeneca: Honoraria|GSK: Honoraria|Merck: Honoraria|Moderna: Honoraria|Novavax: Honoraria|Pfizer: Grant/Research Support|Pfizer: Honoraria|Roche: Honoraria|Seqirus: Grant/Research Support|Seqirus: Honoraria

Rewiring cancer: 3D genome determinants of cancer hallmarks.

In modern cancer biology, Hanahan and Weinberg's classic depiction of the Hallmarks of Cancer serves as a heuristic for understanding malignant phenotypes [1]. Genetic determinants of these phenotypes promote cancer induction and progression, and these mutations drive current approaches to understanding and treating cancer. Meanwhile, for over a century, pathologists have noted that profound alterations of nuclear structure accompany transformation, integrating these changes into diagnostic classifications (Figure 1). Nevertheless, the relationship of nuclear organization to malignant phenotypes has lagged. Recent advances yield profound insight into the 3D genome's relationship with cancer phenotypes, suggesting that spatial genome organization influences many, if not all, of these malignant features. Here, we highlight recent discoveries elucidating connections between 3D genome organization and cancer phenotypes.

Reclassification of Salisediminibacterium haloalkalitolerans Sultanpuram et al. 2015 as a Later Heterotypic Synonym of Salisediminibacterium halotolerans Jiang et al. 2012.

In the present study, the taxonomic position of Salisediminibacterium haloalkalitolerans was evaluated by determining the 16S rRNA gene sequence similarity, genome relatedness, and phylogenetic analyses. The 16S rRNA gene sequences extracted from the genomes of Salisediminibacterium haloalkalitolerans 10nlgT and Salisediminibacterium halotolerans DSM 26530T showed 100% similarity, supporting their classification as the same species. The average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values between S. haloalkalitolerans and S. halotolerans were 97.7 and 80.2%, respectively, above the cutoff value (95-96% ANI; 70% dDDH) for species delineation. S. haloalkalitolerans and S. halotolerans should be classified as the same species because the 16S rRNA gene phylogeny and phylogenomic tree (based on 71 bacterial single-copy genes) showed no genetic divergence between them. Based on the above results and the rule of priority in nomenclature, we propose to reclassify Salisediminibacterium haloalkalitolerans Sultanpuram et al. 2015 as a later heterotypic synonym of Salisediminibacterium halotolerans Jiang et al. 2012.

Bacillus cabrialesii subsp. cabrialesii Strain TE5: A Promising Biological Control Bacterium Against the Causal Agent of Spot Blotch in Wheat.

Strain TE5 was isolated from a wheat (Triticum turgidum L. subsp. durum) rhizosphere grown in a commercial field of wheat in the Yaqui Valley in Mexico. In this work, we present strain TE5 as a promising biological control agent against Bipolaris sorokiniana. First, after its genome sequencing through Illumina NovaSeq, this strain showed a genome size of 4,262,927 bp, with a 43.74% G + C content, an N50 value of 397,059 bp, an L50 value of 4 bp, and 41 contigs (>500 bp). Taxonomical affiliation was carried out by using overall genome relatedness indexes (OGRIs) and the construction of a phylogenomic tree based on the whole genome. The results indicated that strain TE5 identifies with Bacillus cabrialesii subsp. cabrialesii. Genomic annotation using Rapid Annotation Using Subsystems Technology (RAST) and Rapid Prokaryotic Genome Annotation (Prokka) indicated the presence of 4615 coding DNA sequences (CDSs) distributed across 330 subsystems, which included gene families associated with biocontrol, stress response, and iron competition. Furthermore, when the antiSMASH 7.1 platform was used for genome mining, the results indicated the presence of seven putative biosynthetic gene clusters related to the production of biocontrol metabolites, namely subtilosin A, bacillibactin, fengycin, bacillaene, bacilysin, surfactin, and rhizocticin A. Moreover, the antifungal activity of strain TE5 and its cell-free extract (CFE) was evaluated against Bipolaris sorokiniana, an emergent wheat pathogen. The results of in vitro dual confrontation showed fungal growth inhibition of 67% by strain TE5. Additionally, its CFE almost completely inhibited (93%) the growth of the studied phytopathogenic fungus on liquid media. Further observations of the impact of these bacterial metabolites on fungal spore germination exhibited inhibition of fungal spores through degrading the germinative hypha, avoiding mycelium development. Finally, the protective effect of strain TE5 against Bipolaris sorokiniana was evaluated for wheat seedlings. The results showed a significant decrease (83%) in disease severity in comparison with the plant infection without inoculation of the biological control agent. Thus, this work proposes Bacillus cabrialesii subsp. cabrialesii strain TE5 as a promising biological control agent against the wheat pathogen Bipolaris sorokiniana while suggesting lipopeptides as the potential mode of action, together with plant growth and defense stimulation.

First report of the whole‑genome sequence analysis of Fig badnavirus 2 from China.

A novel plant virus was identified in fig trees exhibiting ring spot symptoms through high-throughput sequencing (HTS). The complete genome sequence was successfully determined using PCR and RT-PCR techniques. The virus features a circular DNA genome of 7233 nucleotides (nt) in length, encompassing four open reading frames (ORFs). ORF1 and ORF2 encode hypothetical proteins, while ORF3 encodes a putative polyprotein with conserved domains, including a zinc finger, aspartic protease, reverse transcriptase (RT), and RNase H. ORF4 encodes a putative protein of unknown function. Comparative nucleotide sequence analysis of the RT + RNase H region reveals 84.46% and 78.82% identity with grapevine badnavirus 1 (GBV-1, MF781082.1) and fig badnavirus 1 (FBV-1, MK348055.1), respectively. Notably, this virus's genomic organization diverges from GBV-1 but is similar to FBV-1. Phylogenetic analysis demonstrates that the three isolates of this virus form a distinct clade within the badnaviruses. Based on genomic structure and phylogenetic relationships, this novel virus represents a new member of the genus Badnavirus and is proposed to be named "Fig badnavirus 2" (FBV-2).

The Interplay of Diet, Genome, Metabolome, and Gut Microbiome in Cardiovascular Disease: A Narrative Review.

The responsiveness to dietary interventions is influenced by complex, multifactorial interactions among genetics, diet, lifestyle, gut microbiome, environmental factors, and clinical characteristics, such as the metabolic phenotype. Detailed metabolic and microbial phenotyping using large human datasets is essential for better understanding the link between diet, the gut microbiome, and host metabolism in cardiovascular diseases (CVD). This review provides an overview of the interplay between diet, genome, metabolome, and gut microbiome in CVD. A literature review was conducted using PubMed and Scopus databases to identify pertinent cohort studies published between January 2022 and May 2024. This review focused on English articles that assessed the interplay of diet, genome, metabolome, and gut microbiome in relation to CVD in humans. This narrative review explored the role of single-omics technologies-genomics, metabolomics, and the gut microbiome-and multi-omics approaches to understand the molecular basis of the relationship between diet and CVD. Omics technologies enabled the identification of new genes, metabolites, and molecular mechanisms related to the association of diet and CVD. The integration of multiple omics approaches allows for more detailed phenotyping, offering a broader perspective on how dietary factors influence CVD. Omics approaches hold great potential for deciphering the intricate crosstalk between diet, genome, gut microbiome, and metabolome, as well as their roles in CVD. Although large-scale studies integrating multiple omics in CVD research are still limited, notable progress has been made in uncovering molecular mechanisms. These findings could guide the development of targeted dietary strategies and guidelines to prevent CVD.

TIPPo: A User-Friendly Tool for De Novo Assembly of Organellar Genomes with High-Fidelity Data.

Plant cells have two major organelles with their own genomes: chloroplasts and mitochondria. While chloroplast genomes tend to be structurally conserved, the mitochondrial genomes of plants, which are much larger than those of animals, are characterized by complex structural variation. We introduce TIPPo, a user-friendly, reference-free assembly tool that uses PacBio high-fidelity long-read data and that does not rely on genomes from related species or nuclear genome information for the assembly of organellar genomes. TIPPo employs a deep learning model for initial read classification and leverages k-mer counting for further refinement, significantly reducing the impact of nuclear insertions of organellar DNA on the assembly process. We used TIPPo to completely assemble a set of 54 complete chloroplast genomes. No other tool was able to completely assemble this set. TIPPo is comparable with PMAT in assembling mitochondrial genomes from most species but does achieve even higher completeness for several species. We also used the assembled organelle genomes to identify instances of nuclear plastid DNA (NUPTs) and nuclear mitochondrial DNA (NUMTs) insertions. The cumulative length of NUPTs/NUMTs positively correlates with the size of the nuclear genome, suggesting that insertions occur stochastically. NUPTs/NUMTs show predominantly C:G to T:A changes, with the mutated cytosines typically found in CG and CHG contexts, suggesting that degradation of NUPT and NUMT sequences is driven by the known elevated mutation rate of methylated cytosines. Small interfering RNA loci are enriched in NUPTs and NUMTs, consistent with the RdDM pathway mediating DNA methylation in these sequences.

Genome-based reclassification of Suonthocola fibrivorans as a later heterotypic synonym of Diplocloster agilis.

Both the genera Suonthocola and Diplocloster are members of the family Lachnospiraceae. Their type species, both Suonthocola fibrivorans Sanger_33T and Diplocloster agilis ASD5720T, were isolated from human faeces. A comparison of their 16S rRNA gene sequences revealed 100% similarity, suggesting their close relatedness and the possibility of belonging to the same species. To clarify their taxonomic relationship, genome-based analyses were carried out. Overall genomic relatedness indices analyses indicated that S. fibrivorans Sanger_33T shared average amino acid identity and percentage of conserved proteins prediction values higher than the Lachnospiraceae-specific genus-level thresholds with D. agilis ASD5720T, as well as the other two existing species of the genus Diplocloster. Additionally, S. fibrivorans Sanger_33T formed a distinct branch with D. agilis ASD5720T, clustering with the other two species of the genus Diplocloster into the same clade in both the 16S rRNA gene phylogenetic tree and the core-genome phylogenomic tree. Essentially, both the average nucleotide identity and digital DNA-DNA hybridization prediction values between S. fibrivorans Sanger_33T and D. agilis ASD5720T were above the recommended species boundaries. It is thus clear that S. fibrivorans Sanger_33T and D. agilis ASD5720T constitute the same species. On the basis of the earliest valid publication, priority is given to D. agilis Chaplin et al. 2022. Based on this, the orphan species S. fibrivorans Hitch et al. 2022 is reclassified as a later heterotypic synonym of D. agilis Chaplin et al. 2022, along with the reclassification of the genus Suonthocola Hitch et al. 2022 as a later synonym of Diplocloster Chaplin et al. 2022.

Quantifying the Evolutionary Dynamics of Structure and Content in Closely Related E. coli Genomes.

Bacterial genomes primarily diversify via gain, loss, and rearrangement of genetic material in their flexible accessory genome. Yet the dynamics of accessory genome evolution are very poorly understood, in contrast to the core genome where diversification is readily described by mutations and homologous recombination. Here, we tackle this problem for the case of very closely related genomes. We comprehensively describe genome evolution within n=222 genomes of Escherichia coli ST131, which likely shared a common ancestor around 100 years ago. After removing putative recombinant diversity, the total length of the phylogeny is 6,000 core genome substitutions. Within this diversity, we find 22 modifications to core genome synteny and estimate around 2,000 structural changes within the accessory genome, i.e. one structural change for every three core genome substitutions. Sixty-three percent of loci with structural diversity could be resolved into individual gain and loss events with 10-fold more gains than losses, demonstrating a dominance of gains due to insertion sequences and prophage integration. Our results suggest the majority of synteny changes and insertions in our dataset are likely deleterious and only persist for a short time before being removed by purifying selection.

Phenylobacterium ferrooxidans sp. nov., isolated from a sub-surface geothermal aquifer in Iceland.

A novel bacterial strain, HK31-GT, was isolated from a subsurface geothermal aquifer (Hellisheidi, SW-Iceland) and was characterized using a polyphasic taxonomic approach. Phylogenetic analysis of 16S rRNA gene along with phylogenomic position indicated that the novel strain belongs to the genus Phenylobacterium. Cells are motile Gram-negative thin rods. Physiological characterization showed that strain HK31-GT is a mesophilic bacterium able to grow from 10 to 30°C, at pH values between 6 and 8 and at NaCl concentrations between 0 and 0.5%. Optimal growth was observed without sodium chloride at 25°C and pH6. Strain HK31-GT is chemoorganoheterotroph and its major saturated fatty acids are C18:1ω7c, C16:1ω6c and C16:0, the predominant quinone is Q-10 and the major polar lipid is phosphatidylglycerol. The new strain also possesses the capacity to use ferrous iron (Fe(II)) as the sole energy source and can also be considered as a chemolithoautotrophic microorganism. The overall genome of strain HK31-GT was estimated to be 4.46 Mbp in size with a DNA G+C content of 67.95%. Genes involved in iron metabolism were identified, but no genes typically involved in Fe(II)-oxidation were found. According to the overall genome relatedness indices (OGRI) values, six MAGs from groundwater have been assigned to the same species as the new strain HK31-GT. Furthermore, OGRI values between the genome of strain HK31-GT and the genomes of its closest relatives are below the species delineation threshold. Therefore, given the polyphasic approach used, strain HK31-GT represents a novel species of the genus Phenylobacterium, for which the name Phenylobacterium ferrooxidans sp. nov. is proposed. The type strain is HK31-GT (DSM 116432T=UBOCC-M-3429T=LMG 33376T).

Clostridioides difficile recovered from hospital patients, livestock and dogs in Nigeria share near-identical genome sequences.

Genomic data on Clostridioides difficile from the African continent are currently lacking, resulting in the region being under-represented in global analyses of C. difficile infection (CDI) epidemiology. For the first time in Nigeria, we utilized whole-genome sequencing and phylogenetic tools to compare C. difficile isolates from diarrhoeic human patients (n=142), livestock (n=38), poultry manure (n=5) and dogs (n=9) in the same geographic area (Makurdi, north-central Nigeria) and relate them to the global C. difficile population. In addition, selected isolates were tested for antimicrobial susceptibility (n=33) and characterized by PCR ribotyping (n=53). Hierarchical clustering of core-genome multilocus sequence typing (cgMLST) allelic profiles revealed large diversity at the level HC150 (i.e. clusters of related genomes with maximally 150 pairwise allelic differences), which was previously shown to correlate with PCR ribotypes (RT). While several globally disseminated strains were detected, including HC150_1 (associated with RT078), HC150_3 (RT001) and HC150_3622 (RT014), 42 HC150 clusters (79%) represented unique genotypes that were new to the public genomic record, and 16 (30%) of these were novel PCR ribotypes. Considerable proportions of the C. difficile isolates displayed resistance to fluoroquinolones, macrolides and linezolid, potentially reflecting human and animal antibiotic consumption patterns in the region. Notably, our comparative phylogenomic analyses revealed human-human, human-livestock and farm-farm sharing of near-identical C. difficile genomes (≤2 core-genome allelic differences), suggesting the continued spread of multiple strains across human and animal (pig, poultry, cattle and dog) host populations. Our findings highlight the interconnectivity between livestock production and the epidemiology of human CDI and inform the need for increased CDI awareness among clinicians in this region. A large proportion of C. difficile strains appeared to be unique to the region, reflecting both the significant geographic patterning present in the C. difficile population and a general need for additional pathogen sequencing data from Africa.

SPREAD: Spatiotemporal Pathogen Relationships and Epidemiological Analysis Dashboard.

In the scope of public health, the rapid identification and control of infectious disease outbreaks are a paramount concern. Traditional surveillance methods often face challenges in effectively combining genetic, geographical, and temporal data, which is crucial for a comprehensive understanding of disease transmission dynamics. Addressing this critical need, the Spatiotemporal Phylogenomic Research and Epidemiological Analysis Dashboard (SPREAD) emerges as an innovative standalone web-based application. SPREAD integrates several modules for detailed genomic relationships, pinpointing genetically close pathogens, and spatial mapping, providing in-depth views of how diseases spread across populations and territories, with significant advantage to manage both bacteria and viruses based on allele and variant calling, respectively. Designed for broad accessibility, SPREAD operates seamlessly within web browsers, eliminating the need for sophisticated IT infrastructure and facilitating its use across various public health contexts. Its intuitive interface ensures that users can effortlessly navigate complex datasets, facilitating widespread access to advanced surveillance capabilities. Through its initial deployments, SPREAD has proven instrumental in quickly identifying transmission clusters, significantly aiding in the formulation of prompt and targeted public health responses. Through the integration of state-of-the-art technology with a focus on user-centered design, SPREAD offers a promising solution that highlights the potential of digital health innovations.

Arvimicrobium flavum gen. nov., sp. nov., A Novel Genus in the Family Phyllobacteriaceae Isolated From Forest Soil.

During the study of microbial diversity of forest soil in the Republic of Korea, a yellow pigment-producing, Gram-stain-negative, rod-shaped, motile bacterium was isolated and designated as strain 1W2T. This strain grew at temperature of 10-37°C, at pH of 5.0-9.0, and at NaCl concentration of 0-3.0% (w/v). The 16S rRNA gene sequencing and genome sequencing revealed that strain 1W2T is a member of the family Phyllobacteriaceae but exhibits low similarity with known genera, suggesting that this strain is a new genus within the family. This strain showed the closest similarity to the genera Mesorhizobium (96.6-96.9%), Aminobacter (96.4 -96.6%), Aquamicrobium (96.5-96.7%), and Pseudaminobacter (96.6-96.7%). The nearest relative of 1W2T was Mesorhizobium shangrilense CCBAU 65327T with the 16S rRNA gene sequence similarity of 96.9%. The genome size was 5,545,526bp with DNA G + C content of 64.7%. The values of overall genomic relatedness indices between strain 1W2T and the reference members were 20.4-21.3% for digital DNA-DNA hybridization, 74.0-76.6% for average nucleotide identity, and 68.1-61.2% for amino acids identity. Chemotaxonomic profiling revealed that Q-10 was the sole ubiquinone; summed feature 8 (C18:1ω7c and/or C18:1ω6c), iso-C13:0, and C19:0 cyclo ω8c were the predominant fatty acids; and diphosphatidylglycerol, phosphatidylglycerol, phosphatidylmethylethanolamine, phosphatidylcholine, and phosphatidylethanolamine were the major polar lipids. Based on these data, strain 1W2T represents a novel species of a new genus in the family Phyllobacteriaceae. Accordingly, we proposed the name Arvimicrobium flavum gen. nov., sp. nov., with the type strain 1W2T (= KCTC 92441T = NBRC 116019T).

Performance of phenomic selection in rice: Effects of population size and genotype-environment interactions on predictive ability

Phenomic prediction (PP), a novel approach utilizing Near Infrared Spectroscopy (NIRS) data, offers an alternative to genomic prediction (GP) for breeding applications. In PP, a hyperspectral relationship matrix replaces the genomic relationship matrix, potentially capturing both additive and non-additive genetic effects. While PP boasts advantages in cost and throughput compared to GP, the factors influencing its accuracy remain unclear and need to be defined. This study investigated the impact of various factors, namely the training population size, the multi-environment information integration, and the incorporations of genotype x environment (GxE) effects, on PP compared to GP. We evaluated the prediction accuracies for several agronomically important traits (days to flowering, plant height, yield, harvest index, thousand-grain weight, and grain nitrogen content) in a rice diversity panel grown in four distinct environments. Training population size and GxE effects inclusion had minimal influence on PP accuracy. The key factor impacting the accuracy of PP was the number of environments included. Using data from a single environment, GP generally outperformed PP. However, with data from multiple environments, using genotypic random effect and relationship matrix per environment, PP achieved comparable accuracies to GP. Combining PP and GP information did not significantly improve predictions compared to the best model using a single source of information (e.g., average predictive ability of GP, PP, and combined GP and PP for grain yield were of 0.44, 0.42, and 0.44, respectively). Our findings suggest that PP can be as accurate as GP when all genotypes have at least one NIRS measurement, potentially offering significant advantages for rice breeding programs, reducing the breeding cycles and lowering program costs.