Chowdhury Goutam, Hoshiko Yuki, Okuno Miki, Kitahara Kei, Albert M John, Miyoshi Shin-Ichi, Ogura Yoshitoshi, Dutta Shanta, Ramamurthy Thandavarayan, Mukhopadhyay Asish K
Division of Bacteriology, ICMR-National Institute of Cholera and Enteric Diseases, Kolkata, India.
Collaborative Research Centre of Okayama University for Infectious Diseases, ICMR-National Institute of Cholera and Enteric Diseases, Kolkata, India.
Microb Genom. 2025 Apr;11(4). doi: 10.1099/mgen.0.001363.
is a Gram-negative facultative anaerobic bacterium that causes diarrhoea in humans. This study shows the isolation of from hospitalized paediatric diarrhoeal cases and genome-based characteristics with putative virulence factors and antimicrobial resistance. isolates were identified by species-specific PCR, targeting the gene encoding cytolethal distending toxin (). The genome of was sequenced to identify (i) genes encoding virulence factors (ii) antibiotic resistance-encoding genes, including the mobile genetic elements and (iii) core gene-based phylogenetic relationships and pan-genome features. A total of 10 (1.2%) isolates were isolated from 854 faecal samples, of which 6 (60%) were found as the sole pathogen and the remaining 4 (40%) were identified along with other pathogens, such as enteroaggregative , rotavirus and adenovirus. Patients from whom was isolated presented cholera-like diarrhoea, i.e. with watery stool (60%) with moderate dehydration (100%), fever (20%) and abdominal pain (20%). The antimicrobial susceptibility testing of showed that most of the isolates were susceptible or reduced susceptible to most of the antibiotics except resistance to erythromycin (80%), tetracycline (50%), nalidixic acid (40%), ampicillin (40%), doxycycline (30%) and ceftriaxone (20%). In the whole-genome sequence, isolates revealed several virulence-encoding genes, namely the intimin (, attaching and effacing), the cytolethal distending toxin type II subunit A (), adhesion (, porcine attaching- and effacing-associated), non-LEE (locus of enterocyte effacement) encoded effector A () and antimicrobial resistance genes (ARGs) conferring resistance to tetracycline (, ), sulphonamides (), fluoroquinolones () and beta-lactamases ( , a). The SNP-based phylogenetic analysis of 647 whole genomes of isolates from the National Center for Biotechnology Information databases did not reveal any comparable clustering pattern based on the biological source and place of isolation. The genome of some of the was closely related to those of the isolates from China and the United Kingdom. The PFGE patterns revealed that most of the isolates were distinct clones. This study reports on the extensive genome analysis of diarrhoea-associated harbouring multiple virulence and ARGs.
是一种革兰氏阴性兼性厌氧菌，可导致人类腹泻。本研究展示了从住院儿科腹泻病例中分离出的 ，以及基于基因组的具有假定毒力因子和抗菌耐药性的特征。通过针对编码细胞致死膨胀毒素（）的基因进行种特异性 PCR 鉴定 分离株。对 的基因组进行测序，以确定（i）编码毒力因子的基因，（ii）编码抗生素耐药性的基因，包括移动遗传元件，以及（iii）基于核心基因的系统发育关系和泛基因组特征。从 854 份粪便样本中总共分离出 10 株（1.2%） 分离株，其中 6 株（60%）被发现是唯一病原体，其余 4 株（40%）与其他病原体一起被鉴定出来，如肠集聚性 、轮状病毒和腺病毒。分离出 的患者出现霍乱样腹泻，即水样便（60%）、中度脱水（100%）、发热（20%）和腹痛（20%）。对 的抗菌药敏试验表明，除对红霉素（80%）、四环素（50%）、萘啶酸（40%）、氨苄西林（40%）、强力霉素（30%）和头孢曲松（20%）耐药外，大多数分离株对大多数抗生素敏感或敏感性降低。在全基因组序列中， 分离株揭示了几个编码毒力的基因，即紧密黏附素（ ，紧密黏附和脱落）、细胞致死膨胀毒素 II 型亚基 A（）、黏附素（ ，猪紧密黏附和脱落相关）、非 LEE（肠上皮细胞脱落位点）编码效应子 A（）以及赋予对四环素（ ， ）、磺胺类药物（）、氟喹诺酮类（）和β-内酰胺酶（ ，a）耐药性的抗菌耐药基因（ARGs）。基于单核苷酸多态性（SNP）对来自美国国立生物技术信息中心数据库的 分离株的 647 个全基因组进行的系统发育分析未揭示基于生物来源和分离地点的任何可比聚类模式。部分 的基因组与来自中国和英国的分离株的基因组密切相关。脉冲场凝胶电泳（PFGE）图谱显示，大多数 分离株是不同的克隆。本研究报告了对携带多种毒力和 ARGs 的腹泻相关 的广泛基因组分析。
