scholarly journals Molecular characterisation of theChlamydia pecorumplasmid from porcine, ovine, bovine, and koala strains indicates plasmid-strain co-evolution

PeerJ ◽  
2016 ◽  
Vol 4 ◽  
pp. e1661 ◽  
Author(s):  
Martina Jelocnik ◽  
Nathan L. Bachmann ◽  
Helena Seth-Smith ◽  
Nicholas R. Thomson ◽  
Peter Timms ◽  
...  

Background.Highly stable, evolutionarily conserved, small, non-integrative plasmids are commonly found in members of theChlamydiaceaeand, in some species, these plasmids have been strongly linked to virulence. To date, evidence for such a plasmid inChlamydia pecorumhas been ambiguous. In a recent comparative genomic study of porcine, ovine, bovine, and koalaC. pecorumisolates, we identified plasmids (pCpec) in a pig and three koala strains, respectively. Screening of further porcine, ovine, bovine, and koalaC. pecorumisolates for pCpec showed that pCpecis common, but not ubiquitous inC. pecorumfrom all of the infected hosts.Methods.We used a combination of (i) bioinformatic mining of previously sequencedC. pecorumgenome data sets and (ii) pCpec PCR-amplicon sequencing to characterise a further 17 novel pCpecs inC. pecorumisolates obtained from livestock, including pigs, sheep, and cattle, as well as those from koala.Results and Discussion.This analysis revealed that pCpec is conserved with all eight coding domain sequences (CDSs) present in isolates from each of the hosts studied. Sequence alignments revealed that the 21 pCpecs show 99% nucleotide sequence identity, with 83 single nucleotide polymorphisms (SNPs) shown to differentiate all of the plasmids analysed in this study. SNPs were found to be mostly synonymous and were distributed evenly across all eight pCpecCDSs as well as in the intergenic regions. Although conserved, analyses of the 21 pCpecsequences resolved plasmids into 12 distinct genotypes, with five shared between pCpecs from different isolates, and the remaining seven genotypes being unique to a single pCpec. Phylogenetic analysis revealed congruency and co-evolution of pCpecs with their cognate chromosome, further supporting polyphyletic origin of the koalaC. pecorum. This study provides further understanding of the complex epidemiology of this pathogen in livestock and koala hosts and paves the way for studies to evaluate the function of this putativeC. pecorumvirulence factor.

2020 ◽  
Vol 9 (33) ◽  
Author(s):  
Saswati Biswas ◽  
Indranil Biswas

ABSTRACT Here, we report the complete genome sequence of Streptococcus mutans strain MD, which produces potent mutacins capable of inhibiting streptococci. MD is a relatively uncharacterized strain whose genome information was unavailable. This study provides useful information for comparative genomic study and for understanding the repertoire of mutacins in S. mutans.


F1000Research ◽  
2013 ◽  
Vol 2 ◽  
pp. 265 ◽  
Author(s):  
Oksana Lukjancenko ◽  
Martin Christen Thomsen ◽  
Mette Voldby Larsen ◽  
David Wayne Ussery

PanFunPro is a tool for pan-genome analysis that integrates functional domains from three Hidden Markov Models (HMM) collections, and uses this information to group homologous proteins into families based on functional domain content. We use PanFunPro to compare a set of Lactobacillus and Streptococcus genomes. The example demonstrates that this method can provide analysis of differences and similarities in protein content within user-defined sets of genomes. PanFunPro can find various applications in a comparative genomic study, starting with the basic comparison of newly sequenced isolates to already existing strains, and an estimation of shared and specific genomic content. Furthermore, it can potentially be used in the determination of target sequences for in silico bacterial identification, as well as for epidemiological studies.


mBio ◽  
2021 ◽  
Author(s):  
Laura N. Rusche

Candida auris is an emerging fungal pathogen that is thermotolerant and often resistant to standard antifungal treatments. To trace its evolutionary history, the Sanyal lab conducted a comparative genomic study focusing on the positions of centromeres in C. auris and eight other species from the Clavispora / Candida clade of yeasts (A.


2021 ◽  
Author(s):  
Abhirami Krishnamoorthy Sundaresan ◽  
Keerthana Vincent ◽  
Ganesh Babu Malli Mohan ◽  
Jayapradha Ramakrishnan

Abstract Klebsiella pneumoniae is an important ESKAPE pathogen that causes sepsis, urinary tract infections, peritonitis, intraabdominal abscesses and upper respiratory infections. The strains exhibiting multidrug resistance and hypervirulence are priority pathogens for which immediate treatment and dissemination prevention strategies are required. The hypervirulent drug resistant K. pneumoniae is associated with high mortality rates. Numbers of environmental strains also have acquired virulence genes. Hence to gain a better understanding of the spread of antimicrobial resistant genes across the country over 10 years and to delineate environmental and clinical K. pneumoniae, a comparative genomics investigation was made. This is the first comparative genomic study using India isolates of K. pneumoniae, which includes publicly available WGS of 144 clinical and 9 environmental strains collected during 2010–2020. The blaCTX-M-15 was widely distributed in clinical isolates since 2013 and increased over time from 5 % to 30 %. The co-existence of blaNDM and blaOXA was observed in 22 % of clinical strains. Diverse serotypes were found among the 153 K. pneumoniae isolates, of which, K51 (28%) and K64 (21.56%) were majorly found. Most of the K51 isolates belong to ST231 (93.02 %). And more than 50% of KL51 strains were found to have both rmpA and magA. The number of associated virulence genes (rmpA, magA, entB, ybtS, iutA, alls,) appeared to be higher in ST231-KL51 and ST23-KL1 isolates. Of greatest concern, these virulence genes are observed in environmental strains aswell. More than 97% of clinical strains have yersinibactin (ybtS), aerobactin (iutA) genes. Importantly, 98% of ESBL and 62% of carbapenamasen isolates harboured ybtS, iutA and rmpA, magA respectively. The IncF conjugative plasmids are predominant in K. pneumoniae, which contribute to the spread of AMR, and virulence genes. The increasing trend in hypervirulent strains was observed from 2017. The phylogenetic analysis separates the environmental from clinical strains and is characterized by uncommon STs and serotypes. Thus, the study illustrates the K. pneumoniae genomic surveillance in India representing the phylogenetic evolution, STs, AMR, virulence, serotype to provide more attention for immediate treatment and preventing the dissemination of K. pneumoniae.


PLoS ONE ◽  
2021 ◽  
Vol 16 (9) ◽  
pp. e0258019
Author(s):  
Ishtiaque Ahammad ◽  
Mohammad Uzzal Hossain ◽  
Anisur Rahman ◽  
Zeshan Mahmud Chowdhury ◽  
Arittra Bhattacharjee ◽  
...  

As the COVID-19 pandemic continues to ravage across the globe and take millions of lives and like many parts of the world, the second wave of the pandemic hit Bangladesh, this study aimed at understanding its causative agent, SARS-CoV-2 at the genomic and proteomic level and provide precious insights about the pathogenesis, evolution, strengths and weaknesses of the virus. As of Mid-June 2021, over 1500 SARS-CoV-2 genomesequences have been deposited in the GISAID database from Bangladesh which were extracted and categorized into two waves. By analyzing these genome sequences, it was discovered that the wave-2 samples had a significantly greater average rate of mutation/sample (30.79%) than the wave-1 samples (12.32%). Wave-2 samples also had a higher frequency of deletion, and transversion events. During the first wave, the GR clade was the most predominant but it was replaced by the GH clade in the latter wave. The B.1.1.25 variant showed the highest frequency in wave-1 while in case of wave-2, the B.1.351.3 variant, was the most common one. A notable presence of the delta variant, which is currently at the center of concern, was also observed. Comparison of the Spike protein found in the reference and the 3 most common lineages found in Bangladesh namely, B.1.1.7, B.1.351, B.1.617 in terms of their ability to form stable complexes with ACE2 receptor revealed that B.1.617 had the potential to be more transmissible than others. Importantly, no indigenous variants have been detected so far which implies that the successful prevention of import of foreign variants can diminish the outbreak in the country.


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