Department of Microbiology, Kohat University of Science and Technology, Kohat, 26000, Pakistan.
Department of Microbiology, Women University Swabi, Swabi, Pakistan.
Arch Microbiol. 2023 Apr 7;205(5):175. doi: 10.1007/s00203-023-03523-x.
Shigellosis is the main cause of food and waterborne diarrhea and is an emerging threat to human health. The current study characterized the indigenous multidrug-resistant Shigella flexneri serotypes for their plasmid profiles and genetic diversity, to characterize the plasmid evolutionary patterns and distribution. In total, 199 identified S. flexneri isolates belonging to six different serotypes were analyzed for plasmid profiling, followed by an analysis of whole genome sequencing. All isolates of S. flexneri resistant to antibiotics harbored multiple copies of plasmids with sizes ranging from 1.25 kbp to 9.4 kbp. These isolates were clustered into 22 distinct plasmid patterns, labeled as p1-p22. Among these, p1 (24%) and p10 (13%) were the predominant plasmid profiles. All S. flexneri strains were grouped into 12 clades with a 75% similarity level. Also, a significant association was observed among the plasmid patterns, p23 and p17 with the drug-resistant patterns AMC, SXT, C (19.5%) and OFX, AMC, NA, CIP (13.5%), respectively. Moreover, the most widespread plasmid patterns p4, p10, and p1 showed a significant association with the serotypes 1b (29.16%), 2b (36%), and 7a (100%), respectively. After plasmid sequence assembly and annotation analysis, a variety of small plasmids that vary in size from 973 to 6200 bp were discovered. Many of these plasmids displayed high homology and coverage with plasmids from non-S. flexneri. Several novel plasmids of small size were discovered in multidrug-resistant S. flexneri. The data also showed that plasmid profile analysis is more consistent than antibiotic susceptibility pattern analysis for identifying epidemic strains of S. flexneri isolated in Pakistan.
志贺菌病是食源性和水源性腹泻的主要原因，也是对人类健康的新兴威胁。本研究对地方性多重耐药福氏志贺菌血清型的质粒图谱和遗传多样性进行了特征分析，以描述质粒进化模式和分布。共分析了 199 株鉴定为福氏志贺菌的分离株，这些分离株属于六个不同的血清型，用于质粒图谱分析，随后进行全基因组测序分析。所有对抗生素耐药的福氏志贺菌分离株都携带大小在 1.25 kbp 至 9.4 kbp 之间的多个拷贝质粒。这些分离株被聚类为 22 个不同的质粒图谱，标记为 p1-p22。其中，p1（24%）和 p10（13%）是主要的质粒图谱。所有福氏志贺菌菌株分为 12 个进化枝，相似度为 75%。此外，还观察到质粒图谱 p23 和 p17 与耐药模式 AMC、SXT、C（19.5%）和 OFX、AMC、NA、CIP（13.5%）之间存在显著关联。此外，最广泛的质粒图谱 p4、p10 和 p1 分别与血清型 1b（29.16%）、2b（36%）和 7a（100%）显著相关。在质粒序列组装和注释分析后，发现了多种大小从 973 到 6200 bp 不等的小型质粒。这些质粒中的许多与非福氏志贺菌的质粒具有高度同源性和覆盖度。在多重耐药福氏志贺菌中发现了几种小型新型质粒。数据还表明，与抗生素药敏模式分析相比，质粒图谱分析更能一致地识别在巴基斯坦分离的福氏志贺菌流行株。
