摘要
目的探究侵袭性非伤寒沙门菌(iNTS)的基因组和毒力特征。方法针对收集的7株iNTS菌株开展全基因组测序,通过与相关数据库进行比对检索,对菌株的血清型和基因组信息以及毒力因子进行鉴定、注释和分析。结果 7株iNTS菌株中有6株单相菌,包括1株鼠伤寒血清型、2株I 4,[5],12∶i∶-(ST34型)、2株肠炎血清型、1株科瓦利斯血清型和1株未知血清型I 4,[5],12∶d∶-(ST279型)。基因组组分未发现较一致规律,不同血清型菌株间差别大于同种血清型不同来源菌株。不同血清型沙门菌之间毒力因子分布差异较明显,尚未发现iNTS菌株共有的毒力因子分布特征,荚膜/免疫逃逸、毒素、周生鞭毛、肠菌素Salmochelin可能与菌株高侵袭性相关。所有测试菌株均含有Ⅲ型和VI型分泌系统,且科瓦利斯沙门菌和I 4,[5],12∶d∶-沙门菌的Ⅲ型和VI型分泌系统蛋白数量分别高于其他菌株。分泌系统效应蛋白SseI在部分沙门菌基因组中可能存在与侵袭性增强相关的假基因化。结论暂未在毒力基因水平观察到与iNTS菌株高侵袭性相关的共性致病机制,仍需从功能转录组和蛋白质组层面进行进一步的分析和研究,以确定iNTS发生和传播的遗传基础。
Objective To investigate the genomic and virulence characteristics of seven invasive non-typhoidal Salmonella(iNTS) isolates. Methods Based on the collection of seven iNTS strains, whole genome sequencing were performed. The serotypes, genomes and virulence factors were identified, annotated and analyzed according to the comparison of genome data and relevant databases. Results Among the seven tested iNTS isolates, six were monophasic, including one Salmonella Typhimurium and two Salmonella I 4, [5], 12∶i∶-(ST34 type), two Salmonella Enteritidis, one Salmonella Corvallis and one unknown serotype with the antigenic formulae of I 4, [5], 12∶d∶-(ST279 type). No consistent rule was found in genomic components and relevant parameter differences varies much between different serotypes than those of the same serotype from different sources. The distribution of virulence factors(VF) was significantly different among different Salmonella serotypes, but the common VF characteristics in iNTS strains were not found, though Capsule/Immune evasion, toxin, peritrichousflagella and Salmochelin may be associated with high invasiveness. All tested isolates contained type Ⅲ and type VI secretion systems. The number of secretion protein, type Ⅲ for S. Corvallis and type VI for Salmonella I 4, [5], 12∶d∶-was the highest among the seven isolates. Pseudogenization of the secreted effector SseI may exist among some Salmonella serotypes which may contribute to the enhancement of Salmonella invasiveness. Conclusion The common characteristic differences of virulence factor between iNTS and gastroenteritis NTS were not observed at the moment, and highly invasive pathogenic mechanisms still require further analysis and research at the functional transcriptome and proteomic levels to determine the genetic basis of iNTS occurrence and transmission.
作者
胡豫杰
王伟
许学斌
王艳
崔鑫楠
徐进
李凤琴
HU Yujie;WANG Wei;XU Xuebin;WANG Yan;CUI Xinnan;XU Jin;LI Fengqin(Key Laboratory of Food Safety Risk Assessment of Health,China National Center for Food Safety Risk Assessment,Beijing 100021,China;Institute of Pathogen Microbiology,Shanghai Municipal Center for Disease Control&Prevention,Shanghai 200336,China;Department of Clinical Laboratory,Beijing Jishuitan Hospital,Beijing 100035,China;Food Science and Engineering College,Beijing University of Agriculture,Beijing 102206,China)
出处
《中国食品卫生杂志》
CSCD
北大核心
2021年第3期249-255,共7页
Chinese Journal of Food Hygiene
基金
国家重点研发计划(2018YFC1603900)。
