ABSTRACT
Live attenuated varicella-zoster virus (VZV) vaccines are used to prevent chickenpox and shingles. Single nucleotide polymorphisms (SNPs) that occur during the attenuation of parental strains are critical indicators of vaccine safety. To assess the attenuation of commercial VZV vaccines, genetic variants were comprehensively examined through high-throughput sequencing of viral DNA isolated from four VZV vaccines (Barycela, VarilRix, VariVax, and SKY Varicella). Whole-genome comparison of the four vaccines with the wild-type strain (Dumas) revealed that the sequences are highly conserved on a genome-wide scale. Among the 196 common variants across the four vaccines, 195 were already present in the genome of the parental strain (pOka), indicating that the variants occurred during the generation of the parental strain from the Dumas strain. Compared to the pOka genome, the vaccines exhibited distinct variant frequencies on a genome-wide and within an attenuation-related open reading frame. In particular, attenuation-associated 42 SNPs showed that Barycela, VarilRix, VariVax, and SKY Varicella are in ascending order regarding similarity with pOka-like genotypes, which in turn, might provide genomic evidence for the levels of attenuation. Finally, the phylogenetic network analysis demonstrated that genetic distances from the parental strain correlated with the attenuation levels of the vaccines.
Subject(s)
Chickenpox , Herpes Zoster Vaccine , Herpes Zoster , Humans , Herpesvirus 3, Human/genetics , Chickenpox/prevention & control , Phylogeny , Chickenpox Vaccine/genetics , Herpes Zoster/prevention & control , Genomics , Vaccines, Attenuated/geneticsABSTRACT
A new Vibrio strain, K08M4T, was isolated from the broad-nosed pipefish Syngnathus typhle in the Kiel Fjord. Infection experiments revealed that K08M4T was highly virulent for juvenile pipefish. Cells of strain K08M4T were Gram-stain-negative, curved rod-shaped and motile by means of a single polar flagellum. The strain grew aerobically at 9-40° C, at pH 4-10.5 and it tolerated up to 12 % (w/v) NaCl. The most prevalent (>10 %) cellular fatty acids of K08M4T were C16â:â1 ω7c and C16â:â0. Whole-genome comparisons revealed that K08M4T represents a separate evolutionary lineage that is distinct from other Vibrio species and falls within the Splendidus clade. The genome is 4,886,292 bp in size, consists of two circular chromosomes (3,298,328 and 1,â587,964 bp) and comprises 4,178 protein-coding genes and 175 RNA genes. In this study, we describe the phenotypic features of the new isolate and present the annotation and analysis of its complete genome sequence. Based on these data, the new isolate represents a new species for which we propose the name Vibrio syngnathi sp. nov. The type strain is K08M4T (=DSM 109818T=CECT 30086T).
Subject(s)
Estuaries , Vibrio , Animals , Fatty Acids/chemistry , Phylogeny , Sequence Analysis, DNA , RNA, Ribosomal, 16S/genetics , DNA, Bacterial/genetics , Bacterial Typing Techniques , Base Composition , Fishes , Vibrio/geneticsABSTRACT
Northern pintail (Anas acuta) is a migratory waterfowl that can transmit various viruses. The genome sequence of a Sobemovirus was determined using metagenomic sequencing from the feces of northern pintail (Anas acuta) in Xinjiang, northwest China. The virus possesses a linear RNA molecule of 4177 bp and is most closely related to isolates SoMV-WA (GenBank accession no. HM163159.1) and ATCC PV-109 (GenBank accession no. GQ845002.2), with a nucleotide identity of 86.7%. The virus encodes four open reading frames (ORF) coding for four proteins, and phylogenetic analysis of capsid protein and RNA-dependent RNA polymerase (RdRp) showed that the strain was clustered into the species Sowbane Mosaic Virus (SoMV). The amino acid sequence identity of capsid protein was 89.6-90.9% to other isolates of SoMV, but 17.6-31.4% similar to other strains in the genus Sobemovirus, indicating a strain of Sowbane Mosaic Virus. This is the first report of SoMV in the feces of wild birds and in China, and it suggested that northern pintail likely plays an alternative role in the transmission of SoMV.
Subject(s)
Capsid Proteins , RNA Viruses , Animals , Capsid Proteins/genetics , Phylogeny , Ducks , RNA Viruses/genetics , Feces , Genome, Viral/genetics , Open Reading FramesABSTRACT
The lactic acid bacterium Streptococcus thermophilus is widely used in food production, notably in yogurt fermentation. It evolved under highly specific ecological conditions, resulting in its ability to efficiently metabolize lactose, the main saccharide in milk. However, when used in sweetened dairy products or plant-based products, S. thermophilus may encounter other saccharides (i.e. alone or in mixtures). To date, the bacterium's metabolic capacities in such contexts have been poorly characterized. Here, we explored saccharide utilization by 39 S. thermophilus strains. Using in silico analysis, we discovered that the identity and structure of saccharide utilization genes are conserved across strains, and we identified six saccharides that might be metabolized. Although underlying genetic variability was low, strains nonetheless displayed differences in growth when supplied with different saccharides: lactose, sucrose, fructose, and glucose. Interestingly, we found that strains preferentially used lactose and sucrose in tandem when given saccharide mixtures. Furthermore, we uncovered some main potential drivers of saccharide metabolism in S. thermophilus. Notably, the sucrose transporter ScrA is also responsible for importing glucose. Overall, this research has yielded useful findings that can help the development of new fermented foods, including plant-based products, in which sucrose may serve as a major carbon source.
Subject(s)
Lactose , Streptococcus thermophilus , Animals , Carbon/metabolism , Fermentation , Glucose/metabolism , Lactose/metabolism , Milk/microbiology , Streptococcus thermophilus/genetics , Streptococcus thermophilus/metabolism , Sucrose/metabolismABSTRACT
Dickeya is a major and typical member of soft rot Pectobacteriaceae (SRP) with a wide range of plant hosts worldwide. Previous studies have identified D. zeae as the causal agent of banana soft rot disease in China. In 2017, we obtained banana soft rot pathogen strain FZ06 from the Philippines. Genome sequencing and analysis indicated that FZ06 can be classified as D. dadantii and represents a novel subspecies of D. dadantii, which we propose to name as subsp. paradisiaca. Compared with Chinese banana soft rot pathogenic strain D. zeae MS2, strain FZ06 has a similar host range but different virulence; FZ06 is significantly less virulent to banana and potato but more virulent to Chinese cabbage and onion. Characterization of virulence factors revealed obviously less production of pectate lyases (Pels), polygalacturonases (Pehs), proteases (Prts), and extrapolysaccharides (EPSs), as well as lower swimming and swarming motility and biofilm formation in strain FZ06. Genomic comparison of the two strains revealed five extra gene clusters in FZ06, including one Stt-type T2SS, three T4SSs, and one T4P. Expression of cell wall degrading enzyme (CWDE)-encoding genes is significantly lower in FZ06 than in MS2.
Subject(s)
Gammaproteobacteria , Musa , Dickeya , Philippines , Virulence/genetics , Plant DiseasesABSTRACT
Climate warming, in particular in island environments, where opportunities for species to disperse are limited, may become a serious threat to cold adapted alpine species. In order to understand how alpine species may respond to a warming world, we need to understand the drivers that have shaped their habitat specialisation and the evolutionary adaptations that allow them to utilize alpine habitats. The endemic, endangered New Zealand kea (Nestor notabilis) is considered the only alpine parrot in the world. As a species commonly found in the alpine zone it may be highly susceptible to climate warming. But is it a true alpine specialist? Is its evolution driven by adaptation to the alpine zone, or is the kea an open habitat generalist that simply uses the alpine zone to, for example, avoid lower lying anthropogenic landscapes? We use whole genome data of the kea and its close, forest adapted sister species, the kaka (Nestor meridionalis) to reconstruct the evolutionary history of both species and identify the functional genomic differences that underlie their habitat specialisations. Our analyses do not identify major functional genomic differences between kea and kaka in pathways associated with high-altitude. Rather, we found evidence that selective pressures on adaptations commonly found in alpine species are present in both Nestor species, suggesting that selection for alpine adaptations has not driven their divergence. Strongly divergent demographic responses to past climate warming between the species nevertheless highlight potential future threats to kea survival in a warming world.
Subject(s)
Parrots , Adaptation, Physiological/genetics , Animals , Ecology , Genomics , Microsatellite RepeatsABSTRACT
Keratinases present promising biotechnological applications, due to their ability to degrade keratin. Streptomyces appears as one of the main sources of these enzymes, but complete genome sequences of keratinolytic bacteria are still limited. This article reports the complete genomes of three marine-derived streptomycetes that show different levels of feather keratin degradation, with high (strain G11C), low (strain CHD11), and no (strain Vc74B-19) keratinolytic activity. A multi-step bioinformatics approach is described to explore genes encoding putative keratinases in these genomes. Despite their differential keratinolytic activity, multiplatform annotation reveals similar quantities of ORFs encoding putative proteases in strains G11C, CHD11, and Vc74B-19. Comparative genomics classified these putative proteases into 140 orthologous groups and 17 unassigned orthogroup peptidases belonging to strain G11C. Similarity network analysis revealed three network communities of putative peptidases related to known keratinases of the peptidase families S01, S08, and M04. When combined with the prediction of cellular localization and phylogenetic reconstruction, seven putative keratinases from the highly keratinolytic strain Streptomyces sp. G11C are identified. To our knowledge, this is the first multi-step bioinformatics analysis that complements comparative genomics with phylogeny and cellular localization prediction, for the prediction of genes encoding putative keratinases in streptomycetes.
Subject(s)
Aquatic Organisms/chemistry , Aquatic Organisms/genetics , Computational Biology/methods , Peptide Hydrolases/analysis , Peptide Hydrolases/genetics , Streptomyces/chemistry , Streptomyces/genetics , Aquatic Organisms/microbiology , Genomics , Phylogeny , Streptomyces/isolation & purification , Streptomyces/metabolismABSTRACT
BACKGROUND: Phenotypic convergence between distinct species provides an opportunity to examine the predictability of genetic evolution. Unrelated species sharing genetic underpinnings for phenotypic convergence suggests strong genetic constraints, and thus high predictability of evolution. However, there is no clear big picture of the genomic constraints on convergent evolution. Genome-based phylogenies have confirmed many cases of phenotypic convergence in birds, making them a good system for examining genetic constraints in phenotypic convergence. In this study, we used hierarchical genomic approaches to estimate genetic constraints in three convergent avian traits: nocturnality, raptorial behavior and foot-propelled diving. RESULTS: Phylogeny-based hypothesis tests and positive selection tests were applied to compare 16 avian genomes, representing 14 orders, and identify genes with strong convergence signals. We found 43 adaptively convergent genes (ACGs) associated with the three phenotypic convergence cases and assessed genetic constraints in all three cases, from (amino acid) site mutations to genetic pathways. We found that the avian orders shared few site mutations in the ACGs that contributed to the convergent phenotypes, and that these ACGs were not enriched in any genetic pathways. In addition, different pairs of orders with convergent foot-propelled diving or raptorial behaviors shared few ACGs. We also found that closely related orders that shared foot-propelled diving behavior did not share more ACGs than did distinct orders, suggesting that convergence among these orders could not be explained by their initial genomic backgrounds. CONCLUSIONS: Our analyses of three avian convergence events suggest low constraints for phenotypic convergence across multiple genetic levels, implying that genetic evolution is unpredictable at the phylogenetic level of avian order. Ours is one of first studies to apply hierarchical genomic examination to multiple avian convergent cases to assess the genetic constraints in life history trait evolution.
Subject(s)
Birds/classification , Evolution, Molecular , Phenotype , Phylogeny , Animals , Behavior, Animal , Genomics , Selection, GeneticABSTRACT
BACKGROUND: Genomic comparison of Mycoplasma synoviae vaccine strain MS-H and the MS-H parental strain 86,079/7NS established a preliminary profile of genes related to attenuation of MS-H. In this study we aimed to identify the stability of mutations found in MS-H after passage in experimental or field chickens, and to evaluate if any reverse mutation may be associated with changes in characteristics of MS-H in vitro or in vivo. RESULTS: Whole genome sequence analysis of 5 selected MS-H field reisolates revealed that out of 32 mutations reported previously in MS-H, 28 remained stable, while four found to be reversible to the wild-type. Each isolate possessed mutations in one to three of the genes obg, oppF1 and gap and/or a non-coding region. Examination of the 4 reversible mutations by protein modeling predicted that only two of them (in obg and oppF1 genes) could potentially restore the function of the respective protein to that of the wild-type. CONCLUSIONS: These results suggest that the majority of the MS-H mutations are stable after passage in vaccinated chickens. Characterisation of stable mutations found in MS-H could be utilised to develop rapid diagnostic techniques for differentiation of vaccine from field strains or ts- MS-H reisolates.
Subject(s)
Mycoplasma Infections , Mycoplasma synoviae , Poultry Diseases , Animals , Bacterial Proteins/genetics , Bacterial Vaccines/genetics , Chickens , Mutation , Mycoplasma Infections/prevention & control , Mycoplasma Infections/veterinary , Mycoplasma synoviae/geneticsABSTRACT
BACKGROUND: The broad host range pathogen Sclerotinia sclerotiorum infects over 400 plant species and causes substantial yield losses in crops worldwide. Secondary metabolites are known to play important roles in the virulence of plant pathogens, but little is known about the secondary metabolite repertoire of S. sclerotiorum. In this study, we predicted secondary metabolite biosynthetic gene clusters in the genome of S. sclerotiorum and analysed their expression during infection of Brassica napus using an existing transcriptome data set. We also investigated their sequence diversity among a panel of 25 previously published S. sclerotiorum isolate genomes. RESULTS: We identified 80 putative secondary metabolite clusters. Over half of the clusters contained at least three transcriptionally coregulated genes. Comparative genomics revealed clusters homologous to clusters in the closely related plant pathogen Botrytis cinerea for production of carotenoids, hydroxamate siderophores, DHN melanin and botcinic acid. We also identified putative phytotoxin clusters that can potentially produce the polyketide sclerin and an epipolythiodioxopiperazine. Secondary metabolite clusters were enriched in subtelomeric genomic regions, and those containing paralogues showed a particularly strong association with repeats. The positional bias we identified was borne out by intraspecific comparisons that revealed putative secondary metabolite genes suffered more presence / absence polymorphisms and exhibited a significantly higher sequence diversity than other genes. CONCLUSIONS: These data suggest that S. sclerotiorum produces numerous secondary metabolites during plant infection and that their gene clusters undergo enhanced rates of mutation, duplication and recombination in subtelomeric regions. The microevolutionary regimes leading to S. sclerotiorum secondary metabolite diversity have yet to be elucidated. Several potential phytotoxins documented in this study provide the basis for future functional analyses.
Subject(s)
Ascomycota/genetics , Genome, Fungal/genetics , Host Specificity/genetics , Host-Pathogen Interactions/genetics , Ascomycota/pathogenicity , Biosynthetic Pathways/genetics , Brassica napus/genetics , Brassica napus/microbiology , Computer Simulation , Plant Diseases/genetics , Plant Diseases/microbiology , Recombination, Genetic/genetics , Secondary Metabolism/genetics , Telomere/geneticsABSTRACT
The present study aimed to examine the taxonomic relationship between two species, Paracoccus bengalensis Ghosh et al. 2006 and Paracoccus versutus (Harrison 1983) Katayama et al. 1996. Comparison of 16S rRNA gene sequences revealed that P. bengalensis JJJT was highly similar (99.9 %) to P. versutus A2T. The results of phylogenetic analysis based on 16S rRNA gene sequences indicated that the two strains formed a tight cluster within the genus Paracoccus. Whole genomic comparison between the two strains showed a digital DNA-DNA hybridization estimate of 82. 0â% and an average nucleotide identity value of 98.2 %, clearly indicating that the two strains were members of the same species. Moreover, the type strains of both species shared similar physiological and biochemical properties and fatty acids profiles. Based on genotypic and phenotypic evidence, we conclude that Paracoccus bengalensis Ghosh et al. 2006 is a later heterotypic synonym of Paracoccus versutus (Harrison 1983) Katayama et al. 1996 according to the priority of publication and validation of the name.
Subject(s)
Paracoccus/classification , Phylogeny , Bacterial Typing Techniques , Base Composition , DNA, Bacterial/genetics , Fatty Acids/chemistry , Nucleic Acid Hybridization , RNA, Ribosomal, 16S/genetics , Sequence Analysis, DNAABSTRACT
Newcastle disease, caused by Avian avulavirus 1 (AAvV 1), is endemic to many developing countries around the globe including Pakistan. Frequent epidemics are not uncommon even in vaccinated populations and are largely attributed to the genetic divergence of prevailing isolates and their transmission in the environment. With the strengthening of laboratory capabilities in Pakistan, a number of genetically diverse AAvV 1 strains have recently been isolated and individually characterized in comparison with isolates reported elsewhere in the world. However, there lacks sufficient comparative genomic and phylogenomic analyses of field circulating strains that can elucidate the evolutionary dynamics over a period of time. Herein, we enriched the whole genome sequences of AAvV reported so far (n = 35) from Pakistan and performed comparative genomic, phylogenetic and evolutionary analyses. Based on these analyses, we found only isolates belonging to genotypes VI, VII and XIII of AAvV 1 in a wide range of avian and human hosts. Comparative phylogeny revealed the concurrent circulation of avulaviruses representing different sub-genotypes such as VIg, VIm, VIIa, VIIb, VIIe, VIIf, VIIi, XIIIb and XIIId. We found that the isolates of genotype VII were more closely associated with viruses of genotype XIII than genotype VI. An inter-genotype comparative residue analysis revealed a few substitutions in structurally and functionally important motifs. Putative recombination events were reported for only one of the captive-wild bird (pheasant)-origin isolates. The viruses of genotype VII had a high genetic diversity as compared to isolates from genotypes VI and XIII and, therefore, have more potential to evolve over a period of time. Taken together, the current study provides an insight into the genetic diversity and evolutionary dynamics of AAvV 1 strains circulating in Pakistan. Such findings are expected to facilitate better intervention strategies for the prevention and control of ND in disease-endemic countries across the globe particularly Pakistan.
Subject(s)
Avulavirus/genetics , Birds/virology , Genome, Viral/genetics , Animals , Animals, Wild/virology , Avulavirus Infections/virology , Biological Evolution , Genomics/methods , Genotype , Humans , Newcastle Disease/virology , Newcastle disease virus/genetics , Pakistan , PhylogenyABSTRACT
Angiotensin-converting enzymes, ACE and ACE2, are two main elements in the reninâ»angiotensin system, with a crucial role in the regulation of blood pressure in vertebrates. Previous studies paid much attention to their physiological functions in model organisms, whereas the studies on other animals and related evolution have been sparse. Our present study performed a comprehensive genomic investigation on ace and ace2 genes in vertebrates. We successfully extracted the nucleotide sequences of ace and ace2 genes from high-quality genome assemblies of 36 representative vertebrates. After construction of their evolutionary tree, we observed that most of the phylogenetic positions are consistent with the species tree; however, certain differences appear in coelacanths and frogs, which may suggest a very slow evolutionary rate in the initial evolution of ace and ace2 in vertebrates. We further compared evolutionary rates within the entire sequences of ace and ace2, and determined that ace2 evolved slightly faster than ace. Meanwhile, we counted that the exon numbers of ace and ace2 in vertebrates are usually 25 and 18 respectively, while certain species may occur exon fusion or disruption to decrease or increase their exon numbers. Interestingly, we found three homologous regions between ace and ace2, suggesting existence of gene duplication during their evolutionary process. In summary, this report provides novel insights into vertebrate ace and ace2 genes through a series of genomic and molecular comparisons.
Subject(s)
Evolution, Molecular , Genomics , Peptidyl-Dipeptidase A/genetics , Vertebrates/genetics , Angiotensin II/genetics , Angiotensin II/metabolism , Animals , Exons , Genetic Variation , Genomics/methods , Peptidyl-Dipeptidase A/metabolism , Phylogeny , Renin-Angiotensin System , Signal Transduction , Vertebrates/classification , Vertebrates/metabolismABSTRACT
BACKGROUND: Conservation of single nucleotide polymorphisms (SNPs) between human and other primates (i.e., heterospecific SNPs) in candidate genes can be used to assess the utility of those organisms as models for human biomedical research. METHODS: A total of 59,691 heterospecific SNPs in 22 rhesus macaques and 20 humans were analyzed for human trait associations and 4207 heterospecific SNPs biallelic in both taxa were compared for genetic variation. RESULTS: Variation comparisons at the 4207 SNPs showed that humans were more genetically diverse than rhesus macaques with observed and expected heterozygosities of 0.337 and 0.323 vs. 0.119 and 0.102, and minor allele frequencies of 0.239 and 0.063, respectively. In total, 431 of the 59,691 heterospecific SNPs are reportedly associated with human-specific traits. CONCLUSION: While comparisons between human and rhesus macaque genomes are plausible, functional studies of heterospecific SNPs are necessary to determine whether rhesus macaque alleles are associated with the same phenotypes as their corresponding human alleles.
Subject(s)
Genetic Variation/genetics , Macaca mulatta/genetics , Polymorphism, Single Nucleotide/genetics , Animals , Gene Frequency/genetics , Heterozygote , Humans , Species SpecificityABSTRACT
Clostridium botulinum encompasses bacteria that produce at least one of the seven serotypes of botulinum neurotoxin (BoNT/A-G). The availability of genome sequences of four closely related Type A1 or A1(B) strains, as well as the A1-specific microarray, allowed the analysis of their genomic organizations and evolutionary relationship. The four genomes share >90% core genes and >96% functional groups. Phylogenetic analysis based on COG shows closer relations of the A1(B) strain, NCTC 2916, to B1 and F1 than A1 strains. Alignment of the genomes of the three A1 strains revealed a highly similar chromosomal structure with three small gaps in the genome of ATCC 19397 and one additional gap in the genome of Hall A, suggesting ATCC 19379 as an evolutionary intermediate between Hall A and ATCC 3502. Analyses of the four gap regions indicated potential horizontal gene transfer and recombination events important for the evolution of A1 strains.
Subject(s)
Clostridium botulinum/genetics , Evolution, Molecular , Genome, Bacterial , Chromosome Mapping , Comparative Genomic Hybridization , DNA, Bacterial/genetics , Gene Transfer, Horizontal , Microarray Analysis , Multigene Family , Phylogeny , RNA, Ribosomal, 16S/genetics , Sequence Alignment , Sequence Analysis, DNAABSTRACT
Lignocellulosic materials, made up of cellulose, hemicellulose, and lignin, constitute some of the most prevalent types of biopolymers in marine ecosystems. The degree to which marine microorganisms participate in the breakdown of lignin and their impact on the cycling of carbon in the oceans is not well understood. Strain LCG002, a novel Marivivens species isolated from Lu Chao Harbor's intertidal seawater, is distinguished by its ability to metabolize lignin and various aromatic compounds, including benzoate, 3-hydroxybenzoate, 4-hydroxybenzoate and phenylacetate. It also demonstrates a broad range of carbon source utilization, including carbohydrates, amino acids and carboxylates. Furthermore, it can oxidize inorganic gases, such as hydrogen and carbon monoxide, providing alternative energy sources in diverse marine environments. Its diversity of nitrogen metabolism is supported by nitrate/nitrite, urea, ammonium, putrescine transporters, as well as assimilatory nitrate reductase. For sulfur assimilation, it employs various pathways to utilize organic and inorganic substrates, including the SOX system and DSMP utilization. Overall, LCG002's metabolic versatility and genetic profile contribute to its ecological significance in marine environments, particularly in the degradation of lignocellulosic material and aromatic monomers.
ABSTRACT
Bacterial soft rot caused by coinfection with Dickeya spp. and Pectobacterium spp. in hosts can cause successive changes in fields, and it is difficult to prevent the spread of and control the infection. Pectobacterium spp. are prevalent in the growing areas of tuberous crops, including taro and potato. Recently, Dickeya fangzhongdai has emerged as a virulent pathogen in taro. To determine the prevalence status of the causal agents and evaluate the potential spreading risks of D. fangzhongdai, screening and taxonomic classification were performed on phytopathogenic bacteria collected from different taro-growing areas in Guangdong Province, China, and biological and genomic characteristics were further compared among typical strains from all defined species. The causative agents were verified to be phytobacterial strains of D. fangzhongdai, Pectobacterium aroidearum and Pectobacterium colocasium. P. aroidearum and P. colocasium were found to form a complex preferring Araceae plants and show intensive genomic differentiation, indicating their ancestor had adapted to taro a long time prior. Compared with Pectobacterium spp., D. fangzhongdai was more virulent to taro corms under conditions of exogenous infection and more adaptable at elevated temperatures. D. fangzhongdai strains isolated from taro possessed genomic components of additional T4SSs, which were accompanied by additional copies of the hcp-vgrG genes of the T6SS, and these contributed to the expansion of their genomes. More gene clusters encoding secondary metabolites were found within the D. fangzhongdai strains than within the Pectobacterium complex; interestingly, distinct gene clusters encoding zeamine and arylpolyene were both most similar to those in D. solani that caused potato soft rot. These comparisons provided genomic evidences for that the newly emerging pathogen was potentially equipped to compete with other pathogens. Diagnostic qPCR verified that D. fangzhongdai was prevalent in most of the taro-growing areas and coexisted with the Pectobacterium complex, while the plants enriching D. fangzhongdai were frequently symptomatic at developing corms and adjacent pseudostems and caused severe symptoms. Thus, the emerging need for intensive monitoring on D. fangzhongdai to prevent it from spreading to other taro-growing areas and to other tuberous crops like potato; the adjustment of control strategies based on different pathopoiesis characteristics is recommended.
ABSTRACT
Vibrio parahaemolyticus is a Gram-negative, halophilic and polymorphic coccobacillus. It is world-widely distributed and has resulted in great economic losses since its first appearance. In this study, a pathogenic strain was isolated from diseased pearl gentian grouper and identified as V. parahaemolyticus based on the sequencing results of 16S rDNA gene. In order to gain a comprehensive understanding of this isolation, the whole genome sequencing was conducted. Phylogenetic analysis of the complete genomes of 16 Vibrio species showed that LF1113, ATCC17802, ATCC33787, 2210633, FORC 004, and 160807 were the most closely related. Animal experiments demonstrated that the isolated LF1113 strain was pathogenic in a fish model. This study is the first study to describe the complete genome sequence of a V. parahaemolyticus isolate, which infected pearl gentian grouper from an outbreak in a fish factory farm in Hainan. The results will expand our understanding of genetic characteristics, pathogenesis, diagnostics and disease prevention of V. parahaemolyticus, and lay the foundation for further study.
Subject(s)
Vibrio Infections , Vibrio parahaemolyticus , Animals , Phylogeny , Genomics/methods , Whole Genome Sequencing , Fishes , Vibrio Infections/veterinaryABSTRACT
AIM: To determine Streptococcus agalactiae genes responsible for causing neonatal meningitis. BACKGROUND: Streptococcus agalactiae strain 2603 V/R is causative agent of neonatal meningitis, maternal infection and sepsis in young children. World health organisation reported high burden of new born death caused by this bacterium. Streptococcus agalactiae colonizing epithelial cells of vagina and endothelial cells have high resistance to available antibiotic drugs which makes it essential to determine new drug targets. OBJECTIVES: To compare the genome of selected strain with the non-pathogenic strains of streptococcus and identify the virulent and antibiotic resistant genes for adaptation in host environment. METHOD: The whole genome of human pathogen Streptococcus agalactiae strain 2603 V/R was analysed and compared with Streptococcus dysgalactiae strains using visualization and annotation tools. Genomic islands, mobile genetic elements, virulent and resistant genes were studied. RESULTS: Genetically pathogenic strain is most similar to Streptococcus dysgalactiae subsp. equisimilis strain NCTC 7136. Comparative analysis revealed the importance of capsular polysaccharides and surface proteins responsible for avoiding immune system attachment to host epithelial cells and virulent behaviour. High number of genes coding for antibiotics resistance may provide a competitive advantage for survival of pathogenic Streptococcus agalactiae strain 2603 V/R in its niche. CONCLUSIONS: The comparative analysis of pathogenic strain Streptococcus agalactiae with non-pathogenic strains of Streptococcus dysgalactiae provided new insights in pathogenicity that could aid in recognization for new regions and genes for development of new drug development strategies considering presence of high number of resistance genes.
Subject(s)
Endothelial Cells , Streptococcal Infections , Infant, Newborn , Female , Child , Humans , Child, Preschool , Genome, Bacterial , Streptococcal Infections/microbiology , Streptococcus/genetics , Streptococcus agalactiae/genetics , Anti-Bacterial Agents/pharmacologyABSTRACT
Group B Streptococcus (GBS) is a major cause of several infectious diseases in humans and fish. This study was conducted to compare human and fish-derived GBS in terms of their antimicrobial susceptibility, serotype, virulence and pili genes and sequence type (ST), and to determine whether there is a potential linkage of zoonotic transmission in Malaysia. GBS isolated from humans and fish had similar phenotypic characteristics and differed in virulence gene profile, antimicrobial susceptibility, serotype and sequence type. Fish GBS isolates had lower genetic diversity and higher antibiotic susceptibility than human isolates. We report a rare detection of the potentially fish-adapted ST283 in human GBS isolates. Both human and fish ST283 shared several phenotypic and genotypic features, including virulence and pilus genes and antimicrobial susceptibility, illustrating the value of monitoring GBS within the One Health scope. In this study, two human GBS ST283 isolates belonging to the variant common in fish hosts were identified, raising awareness of the zoonotic potential between the different species in Malaysia.