Zhao S, Mitchell S E, Meng J, Doyle M P, Kresovich S
Center for Food Safety and Quality Enhancement, University of Georgia, Griffin 30223, USA.
FEMS Microbiol Lett. 1995 Nov 1;133(1-2):35-9. doi: 10.1111/j.1574-6968.1995.tb07856.x.
A DNA segment located immediately upstream of the eaeA gene of enterohemorrhagic Escherichia coli O157:H7 strain HA1 was cloned and sequenced. This segment contained an open reading frame encoding a predicted protein of 156 amino acids. A database search identified similar open reading frames upstream of the eaeA gene in two other bacterial pathogens, i.e. enteropathogenic E. coli and Citrobacter freundii. The predicted amino acid sequence of the enterohemorrhagic E. coli protein shared 96.8% and 94.2% identity with the enteropathogenic E. coli and C. freundii sequences, respectively. Because the open reading frame is located within the locus of enterocyte effacement region of the E. coli chromosome, a 'hot spot' for insertion of virulence factor genes, and shares high sequence homology with attaching and effacing EPEC and C. freundii, this protein may be associated with pathogenicity of E. coli O157:H7.
对肠出血性大肠杆菌O157:H7菌株HA1的eaeA基因上游紧邻的一段DNA片段进行了克隆和测序。该片段包含一个开放阅读框，编码一个预测由156个氨基酸组成的蛋白质。数据库搜索发现，在另外两种细菌病原体（即肠致病性大肠杆菌和弗氏柠檬酸杆菌）的eaeA基因上游存在相似的开放阅读框。肠出血性大肠杆菌该蛋白质的预测氨基酸序列与肠致病性大肠杆菌和弗氏柠檬酸杆菌的序列分别具有96.8%和94.2%的同一性。由于该开放阅读框位于大肠杆菌染色体肠上皮细胞损伤区域的位点内，这是毒力因子基因插入的一个“热点”，并且与紧密黏附并消除损伤的肠致病性大肠杆菌和弗氏柠檬酸杆菌具有高度序列同源性，因此该蛋白质可能与大肠杆菌O157:H7的致病性有关。
