[Biological characteristics of an enteroinvasive Escherichia coli strain with tatABC deletion].

OBJECTIVE:To study the relationship between twin-arginine translocation system (Tat) system with the biological characteristics of enteroinvasive Escherichia coli (EIEC). METHODS:Through homologous recombination, we constructed EIEC's tatABC gene deletion strain and complementary strain, and explored their impact on bacterial form, substrate transport function as well as on HeLa cells and guinea pig's corneal invasion force. RESULTS:The tatABC gene deletion strain had apparent changes in bacterial form, loss of substrate transporter function, and significant weakened bacterial invasion force (the number of the deletion strain invading into HeLa cells was decreased significantly, and the ability of its corneal lesion capacity of the guinea pig was significantly weakened), while the complementary strain was similar to the wild strain in the above respects. CONCLUSION:EIEC's Tat protein transport system is closely related with the biological characteristics of EIEC.