Yamamoto T, Echeverria P
Department of Infectious Diseases and Tropical Medicine, Research Institute, International Medical Center of Japan, Tokyo.
Infect Immun. 1996 Apr;64(4):1441-5. doi: 10.1128/iai.64.4.1441-1445.1996.
The sequence of the enteroaggregative Escherichia coli enterotoxin 1 ( EAST1) gene was present in most (or all) strains of human-colonizing enterotoxigenic E. coli (ETEC) with colonization factor antigen II (CFA/II) or CFA/IV (CS6). The EAST1 gene was also strongly associated with PCF09+ ETEC or CFA/I+ ETEC elaborating heat-liable enterotoxin (and heat-stable enterotoxin I). In contrast, CFA/I+ ETEC elaborating heat-stable enterotoxin I, CFA/III+ ETEC, or CS17+ ETEC exhibited very weak or no associated. E. coli from healthy volunteers had no EAST1 gene sequence. A CFA/I+ ETEC strain (H10407) possessed multiple copies of the EAST1 gene on the CFA/I-encoding plasmid and chromosome. In one CFA/II+ ETEC strain, the EAST1 gene was present on the CFA/II-encoding plasmid. The EAST1 gene sequences of the CFA/I+ and CFA/II+ ETEC strains were identical to each other and 99.1% homologous to the reported gene sequence of enteroaggregative E. coli. The data indicate that the EAST1 gene is distributed among ETEC strains with a case of the presence of multiple copies in a single cell and that this distribution is associated with the adherence factor type.
在大多数（或所有）携带定居因子抗原II（CFA/II）或CFA/IV（CS6）的人结肠定植产肠毒素大肠杆菌（ETEC）菌株中，存在聚集性大肠杆菌肠毒素1（EAST1）基因序列。EAST1基因还与产生不耐热肠毒素（和耐热肠毒素I）的PCF09 + ETEC或CFA/I + ETEC密切相关。相比之下，产生耐热肠毒素I的CFA/I + ETEC、CFA/III + ETEC或CS17 + ETEC表现出非常弱的相关性或无相关性。来自健康志愿者的大肠杆菌没有EAST1基因序列。一株CFA/I + ETEC菌株（H10407）在编码CFA/I的质粒和染色体上拥有多个EAST1基因拷贝。在一株CFA/II + ETEC菌株中，EAST1基因存在于编码CFA/II的质粒上。CFA/I +和CFA/II + ETEC菌株的EAST1基因序列彼此相同，与已报道的聚集性大肠杆菌基因序列同源性为99.1%。数据表明，EAST1基因在ETEC菌株中分布，在单个细胞中存在多拷贝情况，且这种分布与黏附因子类型有关。
