Sequence analysis on type II heat labile enterotoxin of Escherichia coli from diarrhaea patients in Liaoning Province, China
YUAN Chao-wen1, JIANG Kui-yu2, ZHANG Li-guo2, LIU Wen-xin3
1. College of Life and Health Sciences,Northeast University, Shenyang 110819, China; 2. Liaoning Center for Animal Disease Emergency, Shenyang 110161, China; 3. Laboratory of Hematology, the Affiliated Hospital of Guangdong Medical College, Zhanjiang 524001, China
Abstract：In this study, we aimed to investigate the prevalence of type II heat labile enterotoxin (LT-II) producing Pathogenic Escherichia coli, and to further analyzed the relationship between elt-II and other virulence factors. From 2014 to 2015, a total of 354 human fecal samples were collected from Liaoning Province, and then 354 E. coli strains were isolated from the fecal samples by using MacConkey agar and biochemical test. The isolated strains were further detected by using PCR method for detecting the virulence factors (elt-II, elt-I, sta, stb, K88, K99, etc.), and the elt-II gene was sequenced in LT-II positive Escherichia coli. Results showed that 139(39.2%) virulence factor positive E. coli were isolated from 354 fecal samples. Of the 139 virulence factor positive E. coli, 12(8.6%) harbored the elt-II gene. Of the 12 elt-II positive strains, 2 harbored the elt-II as the only virulence factor, 6 harbored F1 besides the elt-II gene, 1 harbored K88 besides the elt-II gene, 1 harbored astA besides the elt-II gene, and 2 harbored irp2/ astA besides the elt-II gene. The result of sequencing showed that 10 of the 12 elt-II positive strains harbored the elt-IIc1 subtype, and 2 of the 12 elt-II positive strains harbored the elt-IIc4 subtype. Results indicated that LT-II existed in human resource fecal samples, and LT-IIc1 was the mainly subtype.
袁超文, 江馗语, 张力国, 刘文鑫. 辽宁地区腹泻患者大肠杆菌分离株II型不耐热肠毒素的检测及测序分析[J]. 中国人兽共患病学报, 2016, 32(7): 644-650.
YUAN Chao-wen, JIANG Kui-yu, ZHANG Li-guo, LIU Wen-xin. Sequence analysis on type II heat labile enterotoxin of Escherichia coli from diarrhaea patients in Liaoning Province, China. Chinese Journal of Zoonoses, 2016, 32(7): 644-650.
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2016, Vol. 32 
