The emergence of the tetrathionate reductase operon in the Escherichia coli/Shigella pan-genome.
The emergence of the tetrathionate reductase operon in the Escherichia coli/Shigella pan-genome.
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大肠杆菌致病变异体(致病变种)通常具有明确的毒力特征，由于大肠杆菌基因组具有相当大的可塑性，因此对杂交特性的进化很敏感。我们已经从用于研究动物的纯化饲料中分离出一株菌株，这进一步证明了大肠杆菌获得新的遗传元件的能力，从而有可能出现新的致病变种。利用下一代测序获得全基因组图谱，我们报道了一株非典型的大肠杆菌EcoFA807-17，它具有四硫代酸还原酶(TTR)操纵子，能够利用四硫代酸作为电子受体，从而促进哺乳动物肠道等厌氧环境中的呼吸。Ttr操纵子是几种肠道病原体的有效毒力因子，最突出的是肠道沙门氏菌。然而，在野生型大肠杆菌或志贺氏菌中，染色体整合的四硫酸还原酶基因的存在似乎还没有报道。因此，这种毒力因子的出现可能标志着在大肠杆菌和志贺氏菌中新的致病机制的进化，并可能潜在地改变现有检测方法的有效性，这些检测方法使用四硫酸盐还原酶作为检测肠沙门氏菌的唯一标志。近年来，一些由大肠杆菌引起的食源性疾病暴发的严重性被认为是由于所涉及的致病变种的遗传特征改变而导致的毒力增强所致。在此，我们报告分离出一株具有毒力因子的大肠杆菌，该菌株通常与沙门氏菌或柠檬酸杆菌的胃肠道感染有关。我们进一步详细研究了Genbank中的大肠杆菌、福氏志贺菌和宋内氏志贺氏菌中四硫代酸还原酶基因的范围和分布。
Escherichia coli pathogenic variants (pathovars) are generally characterized by defined virulence traits and are susceptible to the evolution of hybridized identities due to the considerable plasticity of the E. coli genome. We have isolated a strain from a purified diet intended for research animals that further demonstrates the ability of E. coli to acquire novel genetic elements leading potentially to emergent new pathovars. Utilizing next generation sequencing to obtain a whole genome profile, we report an atypical strain of E. coli, EcoFA807‐17, possessing a tetrathionate reductase (ttr) operon, which enables the utilization of tetrathionate as an electron acceptor, thus facilitating respiration in anaerobic environments such as the mammalian gut. The ttr operon is a potent virulence factor for several enteric pathogens, most prominently Salmonella enterica. However, the presence of chromosomally integrated tetrathionate reductase genes does not appear to have been previously reported in wild‐type E. coli or Shigella. Accordingly, it is possible that the appearance of this virulence factor may signal the evolution of new mechanisms of pathogenicity in E. coli and Shigella and may potentially alter the effectiveness of existing assays using tetrathionate reductase as a unique marker for the detection of Salmonella enterica. In recent years, the severity of some outbreaks of food‐borne illness ascribed to Escherichia coli has been recognized as due to enhanced virulence brought about by altered genetic characteristics of the implicated pathovars. Herein, we report the isolation of a strain of E. coli possessing a virulence factor normally associated with gastrointestinal infections by Salmonella or Citrobacter. We further provide a detailed examination of the extent and distribution of the tetrathionate reductase genes within strains of E. coli, Shigella flexneri, and Shigella sonnei deposited in Genbank.
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影响因子：
3.6
作者：
Hensel, M;Hinsley, AP;Berks, BC
通讯作者：
Berks, BC
影响因子：
3.1
作者：
Lan, R;Alles, MC;Reeves, PR
通讯作者：
Reeves, PR
影响因子：
2.2
作者：
Gomig, Franciane;Galvão, Carolina Weigert;Silveira, Rafael Bertoni da
通讯作者：
Silveira, Rafael Bertoni da
影响因子：
6.4
作者：
Bliska JB;van der Velden AW
通讯作者：
van der Velden AW
影响因子：
3.7
作者：
Chaudhuri RR;Sebaihia M;Hobman JL;Webber MA;Leyton DL;Goldberg MD;Cunningham AF;Scott-Tucker A;Ferguson PR;Thomas CM;Frankel G;Tang CM;Dudley EG;Roberts IS;Rasko DA;Pallen MJ;Parkhill J;Nataro JP;Thomson NR;Henderson IR
通讯作者：
Henderson IR