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1.
BMC Genomics ; 21(1): 374, 2020 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-32456612

RESUMO

BACKGROUND: Bacteriophages are bacterial parasites and are considered the most abundant and diverse biological entities on the planet. Previously we identified 154 prophages from 151 serovars of Salmonella enterica subsp. enterica. A detailed analysis of Salmonella prophage genomics is required given the influence of phages on their bacterial hosts and should provide a broader understanding of Salmonella biology and virulence and contribute to the practical applications of phages as vectors and antibacterial agents. RESULTS: Here we provide a comparative analysis of the full genome sequences of 142 prophages of Salmonella enterica subsp. enterica which is the full complement of the prophages that could be retrieved from public databases. We discovered extensive variation in genome sizes (ranging from 6.4 to 358.7 kb) and guanine plus cytosine (GC) content (ranging from 35.5 to 65.4%) and observed a linear correlation between the genome size and the number of open reading frames (ORFs). We used three approaches to compare the phage genomes. The NUCmer/MUMmer genome alignment tool was used to evaluate linkages and correlations based on nucleotide identity between genomes. Multiple sequence alignment was performed to calculate genome average nucleotide identity using the Kalgin program. Finally, genome synteny was explored using dot plot analysis. We found that 90 phage genome sequences grouped into 17 distinct clusters while the remaining 52 genomes showed no close relationships with the other phage genomes and are identified as singletons. We generated genome maps using nucleotide and amino acid sequences which allowed protein-coding genes to be sorted into phamilies (phams) using the Phamerator software. Out of 5796 total assigned phamilies, one phamily was observed to be dominant and was found in 49 prophages, or 34.5% of the 142 phages in our collection. A majority of the phamilies, 4330 out of 5796 (74.7%), occurred in just one prophage underscoring the high degree of diversity among Salmonella bacteriophages. CONCLUSIONS: Based on nucleotide and amino acid sequences, a high diversity was found among Salmonella bacteriophages which validate the use of prophage sequence analysis as a highly discriminatory subtyping tool for Salmonella. Thorough understanding of the conservation and variation of prophage genomic characteristics will facilitate their rational design and use as tools for bacterial strain construction, vector development and as anti-bacterial agents.


Assuntos
Bacteriófagos/genética , Bacteriófagos/fisiologia , Genômica , Salmonella enterica/virologia , Biodiversidade , Evolução Molecular , Genoma Viral/genética , Nucleotídeos/genética , Fases de Leitura Aberta/genética
2.
Int J Syst Evol Microbiol ; 69(8): 2239-2249, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31135334

RESUMO

A novel type strain, designated SDB 2975T (=CECT 9737T=DSM 105892T), of the novel species Staphylococcus debuckii sp. nov. isolated from bovine milk is described. The novel species belongs to the genus Staphylococcus and showed resistance to tetracycline and was oxidase- and coagulase-negative, catalase-positive, and Gram-stain-positive. Phylogenetic relationships of Staphylococcus debuckii SDB 2975T to other staphylococcal species were inferred from 16S rRNA gene and whole-genome-based phylogenetic reconstruction. The 16S rRNA gene comparisons showed that the strain is closely related to Staphylococcus condimenti (99.73 %), Staphylococcus piscifermentans (99.66 %), Staphylococcus carnosus (99.59 %) and Staphylococcus simulans (98.03 %). Average nucleotide identity (ANI) values between S.taphylococcus debuckii SDB 2975T and its closely related Staphylococcus species were 83.96, 94.5, 84.03 and 78.09 %, respectively, and digital DNA-DNA hybridization (dDDH) values were 27.70, 58.02, 27.70 and 22.00 %, respectively. The genome of Staphylococcus debuckii SDB 2975T was sequenced with PacBio and Illumina technologies and is 2 691 850 bp long, has a G+C content of 36.6 mol% and contains 2678 genes and 80 RNAs, including six copies of each5S rRNA, 16S rRNA and 23S rRNA genes. Biochemical profiling and a newly developed PCR assay enabled differentiation of Staphylococcus debuckii SDB 2975T and three other SDB strains from its closest staphylococcal species. Differentiation was also achieved by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF). Genes unique to Staphylococcus debuckii were identified and a PCR-based assay was developed to differentiate Staphylococcus debuckii from other staphylococcal species. In conclusion, the results of phylogenetic analysis along with the ANI values <95 %, and dDDH values <70 % from closely related species along with the phenotypic and biochemical characteristics and specific MALDI-TOF profiles demonstrated that Staphylococcus debuckii SDB 2975T represents a novel species within the genus Staphylococcus, named Staphylococcus debuckii sp. nov. (SDB 2975T=CECT 9737T=DSM 105892T).


Assuntos
Bovinos/microbiologia , Leite/microbiologia , Filogenia , Staphylococcus/classificação , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Hibridização de Ácido Nucleico , Quebeque , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Staphylococcus/isolamento & purificação
3.
Vet Res ; 49(1): 111, 2018 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-30373670

RESUMO

Digital dermatitis (DD) presents as painful, ulcerative or proliferative lesions that lead to bovine lameness affecting economic efficiency and animal welfare. Although DD etiological agent(s) have not been established, it is widely accepted that DD is a polymicrobial disease significantly associated with species of Treponema and the non-linear disease progression may be attributed to interactions among infecting bacteria. We postulated the morphological changes associated with DD lesion grades are related to interactions among infecting species of Treponema. We developed a novel species-specific qPCR that can identify the absolute abundance of the four of the most common species of Treponema in DD, T. phagedenis, T. medium, T. pedis and T. denticola, in a single reaction. We found species abundance and the number of distinct Treponema species present is higher in active, ulcerative lesions than in healing lesions, chronic lesions, and DD-free skin. Treponema spp. were present in both DD-free skin and M3 lesions following treatment with oxytetracycline. We have also found positive correlations among T. phagedenis, T. medium and T. pedis indicating they are significantly more likely to be found together than apart and their absolute quantities tend to increase together, a relationship which is not present with T. denticola. Further, we found Treponema, particularly viable T. denticola, in lesions 5 days post treatment with oxytetracycline (M3). Our findings suggest that pathogenicity may be closely associated with Treponema abundance, particularly T. phagedenis, T. medium and T. pedis, and interactions among them, independent of T. denticola. Our results provide a novel, consistent method to identify species of Treponema within DD lesions and associate Treponema spp. and abundance with morphological changes related to host pathogenicity.


Assuntos
Doenças dos Bovinos/patologia , Treponema/classificação , Infecções por Treponema/veterinária , Animais , Bovinos , Doenças dos Bovinos/microbiologia , Infecções por Treponema/patologia
4.
BMC Vet Res ; 14(1): 63, 2018 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-29499697

RESUMO

BACKGROUND: Staphylococcus aureus, a common cause of bovine mastitis, is known for its ability to acquire to antimicrobial resistance and to secrete numerous virulence factors that can exacerbate inflammation. In addition, alpha-hemolysin has an important role in S. aureus infections, diversity of the hla gene (that produces alpha-hmolysin) in S. aureus isolated from bovine mastitis has not been well characterized. The objective was, therefore, to determine diversity of virulence genes, hla gene sequences, and clonal profiles of S. aureus from bovine mastitis in Chinese dairy herds, and to evaluate inter-relationships. RESULTS: The antimicrobials resistance varies from as low as 1.9% (2/103) for CTX to as high as 76.7% (79/103) for penicilin in the 103 isolates and 46 (44.7%) S. aureus were determined as multi-resistant isolates with diverse resistance patterns. Thirty-eight virulence gene patterns (with variable frequencies) were identified in the 103 isolates and correlated with MLST types, indicating a great diversity. Although the hla gene also had great diversity (14 genotypes), Hla peptides were relatively more conserved. With 7 clonal complexes identified from 24 spa types and 7 MLST types. Regarding the letter, ST 97 was the dominant type in S. aureus from bovine mastitis in China. Furthermore, based on phylogenetic analysis, there was a distinct evolutionary relationship between the hla gene and MLST. CONCLUSION: Multi-resistant S. aureus occurred in bovine mastitis with diverse resistance patterns. The diversity of virulence gene profiles, especially the hla gene and, their relationship with molecular types were reported for the first time in S. aureus from bovine mastitis, which will be useful for future studies on immunogenicity and vaccine development. In addition, based on the distinct evolutionary relationship between the hla gene and MLST types, we inferred that the hla gene has potential role for molecular typing of S. aureus.


Assuntos
Toxinas Bacterianas/genética , Proteínas Hemolisinas/genética , Mastite Bovina/microbiologia , Infecções Estafilocócicas/veterinária , Staphylococcus aureus/genética , Fatores de Virulência/genética , Animais , Bovinos , China/epidemiologia , Resistência Microbiana a Medicamentos/genética , Feminino , Variação Genética/genética , Mastite Bovina/epidemiologia , Testes de Sensibilidade Microbiana/veterinária , Tipagem de Sequências Multilocus/veterinária , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/patogenicidade
5.
Appl Environ Microbiol ; 83(17)2017 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-28667105

RESUMO

Non-aureus staphylococci (NAS), the bacteria most commonly isolated from the bovine udder, potentially protect the udder against infection by major mastitis pathogens due to bacteriocin production. In this study, we determined the inhibitory capability of 441 bovine NAS isolates (comprising 26 species) against bovine Staphylococcus aureus Furthermore, inhibiting isolates were tested against a human methicillin-resistant S. aureus (MRSA) isolate using a cross-streaking method. We determined the presence of bacteriocin clusters in NAS whole genomes using genome mining tools, BLAST, and comparison of genomes of closely related inhibiting and noninhibiting isolates and determined the genetic organization of any identified bacteriocin biosynthetic gene clusters. Forty isolates from 9 species (S. capitis, S. chromogenes, S. epidermidis, S. pasteuri, S. saprophyticus, S. sciuri, S. simulans, S. warneri, and S. xylosus) inhibited growth of S. aureus in vitro, 23 isolates of which, from S. capitis, S. chromogenes, S. epidermidis, S. pasteuri, S. simulans, and S. xylosus, also inhibited MRSA. One hundred five putative bacteriocin gene clusters encompassing 6 different classes (lanthipeptides, sactipeptides, lasso peptides, class IIa, class IIc, and class IId) in 95 whole genomes from 16 species were identified. A total of 25 novel bacteriocin precursors were described. In conclusion, NAS from bovine mammary glands are a source of potential bacteriocins, with >21% being possible producers, representing potential for future characterization and prospective clinical applications.IMPORTANCE Mastitis (particularly infections caused by Staphylococcus aureus) costs Canadian dairy producers $400 million/year and is the leading cause of antibiotic use on dairy farms. With increasing antibiotic resistance and regulations regarding use, there is impetus to explore bacteriocins (bacterially produced antimicrobial peptides) for treatment and prevention of bacterial infections. We examined the ability of 441 NAS bacteria from Canadian bovine milk samples to inhibit growth of S. aureus in the laboratory. Overall, 9% inhibited growth of S. aureus and 58% of those also inhibited MRSA. In NAS whole-genome sequences, we identified >21% of NAS as having bacteriocin genes. Our study represents a foundation to further explore NAS bacteriocins for clinical use.


Assuntos
Bacteriocinas/biossíntese , Leite/microbiologia , Staphylococcus/metabolismo , Animais , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Bovinos , Feminino , Genoma Bacteriano , Família Multigênica , Staphylococcus/classificação , Staphylococcus/genética , Staphylococcus/isolamento & purificação
6.
J Dairy Sci ; 100(12): 9736-9745, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28987586

RESUMO

Assessment of antimicrobial use (AMU) is vital for interpreting the origin of changes in antimicrobial resistance (AMR). The objectives of the present study were to estimate the association between AMU determined using on-farm treatment records (TR) and inventory of empty drug containers (INV). Herds were selected to represent Canadian dairy farms. Producers were asked to record animal health events and treatments on a standard General Health Event form. For inventory data, 40-L receptacles were placed at various locations considered convenient to deposit all empty drug containers. Antimicrobial defined-daily dosages (ADD) were calculated for 51 Canadian herds using the 2 methods. Estimation of AMU was 31,840 ADD using the INV and 14,487 ADD using the TR, indicating that for every TR entry, 2.20 times more treatments were observed using the INV. Mastitis, reproductive conditions, and dry cow therapy were the most frequent reasons for antimicrobial therapy when assessing TR. For all antimicrobials evaluated, mean ADD was higher using the INV versus TR. Regardless, a strong positive correlation (0.80) was observed between the 2 methods, indicating that herds with increased number of ADD recorded using the INV also had increased number of ADD recorded using TR. Furthermore, a positive association was observed for the 6 most commonly used antimicrobials. In comparison to methods used in surveillance programs on AMU in livestock that assume a constant use in all herds (i.e., sales data), INV provided a herd-level specific quantity of AMU positively correlated with AMU recorded at the animal level in general. The INV was easy to implement and provided a measure of total AMU in the herd. Availability of such information would be valuable for interpreting changes in AMR at the herd level and enabling evaluation of interventions for decreasing AMR.


Assuntos
Anti-Infecciosos/uso terapêutico , Indústria de Laticínios/métodos , Embalagem de Medicamentos/estatística & dados numéricos , Prontuários Médicos/estatística & dados numéricos , Animais , Canadá , Bovinos , Feminino
7.
J Dairy Sci ; 100(7): 5592-5612, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28527793

RESUMO

Non-aureus staphylococci (NAS), the microorganisms most frequently isolated from bovine milk worldwide, are a heterogeneous group of numerous species. To establish their importance as a group, the distribution of individual species needs to be determined. In the present study, NAS intramammary infection (IMI) was defined as a milk sample containing ≥1,000 cfu/mL in pure or mixed culture that was obtained from a cohort of cows assembled by the Canadian Bovine Mastitis Research Network. Overall, 6,213 (6.3%) of 98,233 quarter-milk samples from 5,149 cows and 20,305 udder quarters were associated with an NAS IMI. Of the 6,213 phenotypically identified NAS isolates, 5,509 (89%) were stored by the Canadian Bovine Mastitis Research Network Mastitis Pathogen Collection and characterized using partial sequencing of the rpoB housekeeping gene, confirming 5,434 isolates as NAS. Prevalence of each NAS species IMI was estimated using Bayesian models, with presence of a specific NAS species as the outcome. Overall quarter-level NAS IMI prevalence was 26%. The most prevalent species causing IMI were Staphylococcus chromogenes (13%), Staphylococcus simulans (4%), Staphylococcus haemolyticus (3%), Staphylococcus xylosus (2%), and Staphylococcus epidermidis (1%). The prevalence of NAS IMI as a group was highest in first-parity heifers and was evenly distributed throughout cows in parities ≥2. The IMI prevalence of some species such as S. chromogenes, S. simulans, and S. epidermidis differed among parities. Overall prevalence of NAS IMI was 35% at calving, decreased over the next 10 d, and then gradually increased until the end of lactation. The prevalence of S. chromogenes, Staphylococcus gallinarum, Staphylococcus cohnii, and Staphylococcus capitis was highest at calving, whereas the prevalence of S. chromogenes, S. haemolyticus, S. xylosus, and S. cohnii increased during lactation. Although the overall prevalence of NAS IMI was similar across barn types, the prevalence of S. simulans, S. xylosus, S. cohnii, Staphylococcus saprophyticus, S. capitis, and Staphylococcus arlettae IMI was higher in tiestall barns; the prevalence of S. epidermidis IMI was lowest; and the prevalence of S. chromogenes and Staphylococcus sciuri IMI was highest in bedded-pack barns. Staphylococcus simulans, S. epidermidis, S. xylosus, and S. cohnii IMI were more prevalent in herds with intermediate to high bulk milk somatic cell count (BMSCC) and S. haemolyticus IMI was more prevalent in herds with high BMSCC, whereas other common NAS species IMI were equally prevalent in all 3 BMSCC categories. Distribution of NAS species IMI differed among the 4 regions of Canada. In conclusion, distribution differed considerably among NAS species IMI; therefore, accurate identification (species level) is essential for studying NAS epidemiology.


Assuntos
Doenças dos Bovinos/microbiologia , Glândulas Mamárias Animais/microbiologia , Leite/microbiologia , Infecções Estafilocócicas/veterinária , Staphylococcus/isolamento & purificação , Animais , Teorema de Bayes , Canadá/epidemiologia , Bovinos , Doenças dos Bovinos/epidemiologia , Feminino , Mastite Bovina , Gravidez , Prevalência , Especificidade da Espécie , Infecções Estafilocócicas/epidemiologia , Infecções Estafilocócicas/microbiologia , Staphylococcus/classificação
8.
Int J Syst Evol Microbiol ; 66(12): 5575-5599, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27620848

RESUMO

Understanding of the phylogeny and interrelationships of the genera within the order 'Enterobacteriales' has proven difficult using the 16S rRNA gene and other single-gene or limited multi-gene approaches. In this work, we have completed comprehensive comparative genomic analyses of the members of the order 'Enterobacteriales' which includes phylogenetic reconstructions based on 1548 core proteins, 53 ribosomal proteins and four multilocus sequence analysis proteins, as well as examining the overall genome similarity amongst the members of this order. The results of these analyses all support the existence of seven distinct monophyletic groups of genera within the order 'Enterobacteriales'. In parallel, our analyses of protein sequences from the 'Enterobacteriales' genomes have identified numerous molecular characteristics in the forms of conserved signature insertions/deletions, which are specifically shared by the members of the identified clades and independently support their monophyly and distinctness. Many of these groupings, either in part or in whole, have been recognized in previous evolutionary studies, but have not been consistently resolved as monophyletic entities in 16S rRNA gene trees. The work presented here represents the first comprehensive, genome-scale taxonomic analysis of the entirety of the order 'Enterobacteriales'. On the basis of phylogenetic analyses and the numerous identified conserved molecular characteristics, which clearly distinguish members of the order 'Enterobacteriales' and the seven reported clades within this order, a proposal is made here for the order Enterobacterales ord. nov. which consists of seven families: Enterobacteriaceae, Erwiniaceae fam. nov., Pectobacteriaceae fam. nov., Yersiniaceae fam. nov., Hafniaceae fam. nov., Morganellaceae fam. nov., and Budviciaceae fam. nov.


Assuntos
Gammaproteobacteria/classificação , Filogenia , Sequência de Aminoácidos , Técnicas de Tipagem Bacteriana , DNA Bacteriano/genética , Mutação INDEL , Tipagem de Sequências Multilocus , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
9.
Antonie Van Leeuwenhoek ; 109(4): 565-87, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26837779

RESUMO

The evolutionary interrelationships between the archaeal organisms which comprise the class Halobacteria have proven difficult to elucidate using traditional phylogenetic tools. The class currently contains three orders. However, little is known about the family level relationships within these orders. In this work, we have completed a comprehensive comparative analysis of 129 sequenced genomes from members of the class Halobacteria in order to identify shared molecular characteristics, in the forms of conserved signature insertions/deletions (CSIs) and conserved signature proteins (CSPs), which can provide reliable evidence, independent of phylogenetic trees, that the species from the groups in which they are found are specifically related to each other due to common ancestry. Here we present 20 CSIs and 31 CSPs which are unique characteristics of infra-order level groups of genera within the class Halobacteria. We also present 40 CSIs and 234 CSPs which are characteristic of Haloarcula, Halococcus, Haloferax, or Halorubrum. Importantly, the CSIs and CSPs identified here provide evidence that the order Haloferacales contains two main groups, one consisting of Haloferax and related genera supported by four CSIs and five CSPs and the other consisting of Halorubrum and related genera supported by four CSPs. We have also identified molecular characteristics that suggest that the polyphyletic order Halobacteriales contains at least two large monophyletic clusters of organisms in addition to the polyphyletic members of the order, one cluster consisting of Haloarcula and related genera supported by ten CSIs and nineteen CSPs and the other group consisting of the members of the genus Halococcus supported by nine CSIs and 23 CSPs. We have also produced a highly robust phylogenetic tree based on the concatenated sequences of 766 proteins which provide additional support for the relationships identified by the CSIs and CSPs. On the basis of the phylogenetic analyses and the identified conserved molecular characteristics presented here, we propose a division of the order Haloferacales into two families, an emended family Haloferacaceae and Halorubraceae fam. nov. and a division of the order Halobacteriales into three families, an emended family Halobacteriaceae, Haloarculaceae fam. nov., and Halococcaceae fam. nov.


Assuntos
Halobacteriaceae/classificação , Halobacteriales/classificação , Sequência de Aminoácidos , Proteínas Arqueais/genética , Sequência de Bases , Sequência Conservada , DNA Arqueal/análise , DNA Arqueal/genética , Genoma Arqueal , Halobacteriaceae/genética , Halobacteriales/genética , Mutação INDEL , Filogenia , RNA Ribossômico 16S/genética , Alinhamento de Sequência , Análise de Sequência de DNA
10.
Int J Syst Evol Microbiol ; 65(Pt 3): 1050-1069, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25428416

RESUMO

The Halobacteria constitute one of the largest groups within the Archaea. The hierarchical relationship among members of this large class, which comprises a single order and a single family, has proven difficult to determine based upon 16S rRNA gene trees and morphological and physiological characteristics. This work reports detailed phylogenetic and comparative genomic studies on >100 halobacterial (haloarchaeal) genomes containing representatives from 30 genera to investigate their evolutionary relationships. In phylogenetic trees reconstructed on the basis of 32 conserved proteins, using both neighbour-joining and maximum-likelihood methods, two major clades (clades A and B) encompassing nearly two-thirds of the sequenced haloarchaeal species were strongly supported. Clades grouping the same species/genera were also supported by the 16S rRNA gene trees and trees for several individual highly conserved proteins (RpoC, EF-Tu, UvrD, GyrA, EF-2/EF-G). In parallel, our comparative analyses of protein sequences from haloarchaeal genomes have identified numerous discrete molecular markers in the form of conserved signature indels (CSI) in protein sequences and conserved signature proteins (CSPs) that are found uniquely in specific groups of haloarchaea. Thirteen CSIs in proteins involved in diverse functions and 68 CSPs that are uniquely present in all or most genome-sequenced haloarchaea provide novel molecular means for distinguishing members of the class Halobacteria from all other prokaryotes. The members of clade A are distinguished from all other haloarchaea by the unique shared presence of two CSIs in the ribose operon protein and small GTP-binding protein and eight CSPs that are found specifically in members of this clade. Likewise, four CSIs in different proteins and five other CSPs are present uniquely in members of clade B and distinguish them from all other haloarchaea. Based upon their specific clustering in phylogenetic trees for different gene/protein sequences and the unique shared presence of large numbers of molecular signatures, members of clades A and B are indicated to be distinct from all other haloarchaea because of their uniquely shared evolutionary histories. Based upon these results, it is proposed that clades A and B be recognized as two new orders, Natrialbales ord. nov. and Haloferacales ord. nov., within the class Halobacteria, containing the novel families Natrialbaceae fam. nov. and Haloferacaceae fam. nov. Other members of the class Halobacteria that are not members of these two orders will remain part of the emended order Halobacteriales in an emended family Halobacteriaceae.


Assuntos
Genes Arqueais , Halobacteriales/classificação , Filogenia , Sequência de Aminoácidos , Análise por Conglomerados , DNA Arqueal/genética , Halobacteriales/genética , Mutação INDEL , Funções Verossimilhança , Dados de Sequência Molecular , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
11.
Antonie Van Leeuwenhoek ; 108(3): 765-81, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26179278

RESUMO

The phylum Chlamydiae contains nine ecologically and genetically diverse families all placed within a single order. In this work, we have completed a comprehensive comparative analysis of 36 sequenced Chlamydiae genomes in order to identify shared molecular characteristics, namely conserved signature insertions/deletions (CSIs) and conserved signature proteins (CSPs), which can serve as distinguishing characteristics of supra-familial clusters within the phylum Chlamydiae. Our analysis has led to the identification of 32 CSIs which are specific to clusters within the phylum Chlamydiae at various phylogenetic depths. Importantly, 17 CSIs and 98 CSPs were found to be specific for the family Chlamydiaceae while another 3 CSI variants and 15 CSPs were specific for a grouping of the families Criblamydiaceae, Parachlamydiaceae, Simkaniaceae and Waddliaceae. These two clusters were also found to be distinguishable in 16S rRNA based phylogenetic trees, concatenated protein based phylogenetic trees, character compatibility based phylogenetic analyses, and on the basis of 16S rRNA gene sequence identity and average amino acid identity values. On the basis of the identified molecular characteristics, branching in phylogenetic trees, and the genetic distance between the two clusters within the phylum Chlamydiae we propose a division of the class Chlamydiia into two orders: an emended order Chlamydiales, containing the family Chlamydiaceae and the closely related Candidatus family Clavichlamydiaceae, and the novel order Parachlamydiales ord. nov. containing the families Parachlamydiaceae, Simkaniaceae and Waddliaceae and the Candidatus families Criblamydiaceae, Parilichlamydiaceae, Piscichlamydiaceae, and Rhabdochlamydiaceae. We also include a brief discussion of the reunification of the genera Chlamydia and Chlamydophila.


Assuntos
Chlamydiales/classificação , Chlamydiales/genética , Variação Genética , Proteínas de Bactérias/genética , Análise por Conglomerados , Biologia Computacional , Sequência Conservada , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Genoma Bacteriano , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
12.
Antonie Van Leeuwenhoek ; 107(2): 467-85, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25481407

RESUMO

The current taxonomy of the order Xanthomonadales is highly problematic and no comprehensive phylogenomic studies have been completed that include the most divergent members within the order. In this work, we have completed a phylogenomic analysis of a wide range of genomes, five of which were sequenced for the first time for this work, representing the vast majority of the diversity within the order Xanthomonadales. Using comparative genomic techniques, we have identified a large number of conserved signature inserts/deletions (CSIs) that are specifically found in different groups of related organisms, at different taxonomic levels, within the order. Our phylogenetic analyses do not support a monophyletic grouping of the members of the order Xanthomonadales and no CSIs were identified which are uniquely shared by all sequenced species within this order. However, our work has identified 10 CSIs which are specific to all members of the family Xanthomonadaceae and an additional 10 and 11 CSIs that are specific to one of two phylogenetically well-defined clades within the family Xanthomonadaceae. On the basis of the identified CSIs and the results of phylogenomic analyses, we propose a new taxonomic framework for the order Xanthomonadales. In this proposal, the families Algiphilaceae and Solimonadaceae (Nevskiaceae), which do not branch with the other members of the order Xanthomonadales, are transferred into the order Nevskiales ord. nov. The remaining members of the order Xanthomonadales are divided into two families: the family Xanthomonadaceae, containing the genus Xanthomonas and its closest relatives, and a new family, Rhodanobacteraceae fam. nov., containing the genus Rhodanobacter and its closest relatives. Additionally, we have also emended descriptions of the order Lysobacterales, the family Lysobacteraceae, and the family Nevskiaceae to indicate that they are earlier synonyms of the order Xanthomonadales, the family Xanthomonadaceae, and the family Solimonadaceae, respectively.


Assuntos
Gammaproteobacteria/classificação , Gammaproteobacteria/genética , Variação Genética , Filogenia , Análise por Conglomerados , DNA Bacteriano/química , DNA Bacteriano/genética , Mutação INDEL , Dados de Sequência Molecular , Análise de Sequência de DNA
13.
Microbiol Resour Announc ; 12(5): e0008323, 2023 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-37067409

RESUMO

This announcement reports the complete genome sequence of a non-Shiga toxin-producing Escherichia coli strain that was isolated from municipal biosolids collected from a Canadian wastewater treatment plant. This strain contains multiple metal, antimicrobial, and heat resistance genes, as determined by genome sequencing, and could be a useful bacterial model for future studies.

14.
Microbiol Resour Announc ; 11(7): e0029822, 2022 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-35658536

RESUMO

Listeria monocytogenes, a Gram-positive, rod-shaped, non-spore-forming bacterium, is an important foodborne bacterial pathogen for humans worldwide. Here, we report the complete genome sequence of a Canadian Listeria monocytogenes strain with an antimicrobial resistance (AMR) gene that was isolated from lettuce.

15.
Microbiol Resour Announc ; 11(7): e0020022, 2022 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-35658560

RESUMO

Listeria monocytogenes, a Gram-positive, rod-shaped, non-spore-forming bacterium, is an important foodborne bacterial pathogen for humans worldwide, with a high mortality rate. Here, we report the complete genome sequence of a Listeria monocytogenes strain with an antimicrobial resistance (AMR) gene, isolated from sprouts in Canada.

16.
Microbiol Resour Announc ; 11(7): e0027722, 2022 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-35658702

RESUMO

Listeria monocytogenes is a Gram-positive, rod-shaped, non-spore-forming bacterium which is an important foodborne bacterial pathogen for human worldwide with 20-30% mortality. Here, we report circular complete genome sequences of three Listeria monocytogenes strains isolated from the samples of microgreens in Canada.

17.
Microbiol Resour Announc ; 11(7): e0029622, 2022 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-35762752

RESUMO

Listeria monocytogenes is a Gram-positive, rod-shaped, non-spore-forming bacterium that is an important foodborne bacterial pathogen for humans worldwide, with high mortality rates. Here, we report the complete genome sequence of a Listeria monocytogenes strain that was isolated from kale salad in Canada.

18.
Microbiol Resour Announc ; 11(10): e0075622, 2022 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-36190249

RESUMO

Staphylococcus aureus is one of the most important bacterial pathogens causing bovine mastitis, which leads to huge economic losses worldwide. Here, we report draft genome sequences and antimicrobial resistance gene profiles of five Staphylococcus aureus strains that were isolated from bovine milk in Pakistan.

20.
Microbiol Resour Announc ; 10(25): e0041521, 2021 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-34165338

RESUMO

Raoultella planticola is a Gram-negative opportunistic bacterial pathogen associated with hospital-acquired infections in humans. Here, we report the complete genome sequence of one Raoultella planticola strain isolated from Canadian wastewater treatment facilities containing one chromosome and four plasmids with four antimicrobial resistance (AMR) genes and four metal resistance gene clusters.

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