Open AccessGenetic diversity and epidemiology of accessory gene regulator loci in Clostridioides difficile
Author(s) -
Yuta Okada,
Shu Okugawa,
Mahoko Ikeda,
Tatsuya Kobayashi,
Ryoichi Saito,
Yoshimi Higurashi,
Kyoji Moriya
Publication year - 2020
Publication title -
access microbiology
Language(s) - English
Resource type - Journals
ISSN - 2516-8290
DOI - 10.1099/acmi.0.000134
Subject(s) - multilocus sequence typing , biology , clade , genetics , in silico , genetic diversity , phylogenetic tree , gene , typing , genotype , population , medicine , environmental health
Quorum sensing is known to regulate bacterial virulence, and the accessory gene regulator ( agr ) loci is one of the genetic loci responsible for its regulation. Recent reports examiningClostridioides difficileshow that two agr loci, agr1 and agr2, regulate toxin production, but the diversity of agr loci and their epidemiology is unknown. In our study, in silico analysis was performed to research genetic diversity of agr , andC. difficileisolates from clinical samples underwent multilocus sequence typing (MLST) and PCR analysis of agr loci. To reveal the distribution of agr among different strains, phylogenetic analysis was also performed. In our in silico analysis, two different subtypes, named agr2R and agr2M , were found in agr2, which were previously reported. PCR analysis of 133C .difficileisolates showed that 131 strains had agr1 , 61 strains had agr2R , and 26 strains had agr2M; agr2R was mainly found in clade 1 or clade 2 organisms, whereas agr2M was only found in clade 4. With rare exception, agr1 -negative sequence types (STs) belonged to clade C-Ⅰ and C-Ⅲ, and one clade 4 strain had agr2R . Our study revealed subtypes of agr2 not previously recognized, and the distribution of several agr loci inC. difficile . These findings provide a foundation for further functional and clinical research of the agr loci.