Tellurite (TeO3) resistance serves as a selection trait of several pathogenic bacteria and is conferred by various detenninants including ter gene cluster fonned by two associated parts (terffXYZ and terZABCDEF). Mechanism of tellurite resistance in microorganism is not fully understood. In bacterial cells, tellurite was reduced to black metallic tellurium to fonn a black colony. The tellurite resistance operon consists of four essential genes named terBCDE. The role of individual proteins in tellurite resistance operon is still unknown. In the present study, terE gene was amplified by PCR and cloned into the expression vector pET2Ia(+) resulting in pEterE. The TerE protein was successfully expressed in E. coli strain BL2l (DE3) and purified by Ni-NTA agarose affinity column. The complementation test was perfonned to verify biological function of recombinant protein. The pKLdelE plasmid-the deletion of terE gene was transfonned into cells containing pEterE plasmid. The growth of cells containing two plasmids on LB media with K2TeO3 and fonned black colonies indicated that biological function of recombinant protein was not damaged. The co-expression of two proteins in cells was achieved by using two-plasmid systems and through that we have identified interactions among tellurite resistance proteins (Ter). The interaction among TerE protein and Ter proteins was also identified. Results showed that TerE protein has interacted with TerB and TerD proteins. The dimeric fonn of TerE protein has been also detected. The preliminary results ofthe interaction between protein TerE with other essential proteins ofTeR operon provide initial suggestions to understand mechanisms oftellurite resistance of bacteria.
Lọc theo danh mục
Lượt truy cập :
16,253,014
Xem toàn văn