Expression and regulation of the operon of in human trophoblast cells.

Brucellosis is primarily a disease of domestic animals in which the bacteria localizes to fetal tissues such as embryonic trophoblast cells and fluids containing erythritol, which stimulates . growth. The utilization of erythritol is a characteristic of the genus . The operon contains four genes (, , and ) for the utilization of erythritol, and plays a major role in the survival and multiplication of . The objective of the present study was to conduct a preliminary characterization of differential genes expression of the operon at several time points after infected embryonic trophoblast cells (HPT-8 cells). The result showed that the operon expression was higher in HPT-8 cells compared with the medium. The relative expression of , and peaked at 2 h post-infection in HPT-8 cells, and expression peaked at 3 h post-infection. The expression of , and may be inhibited by increased expression. However, the expression of the operon was stable in the presence of erythritol in cells. 2308Δ and 027Δ mutants of the operon were successfully constructed by homologous recombination, which were attenuated in RAW 264.7 murine macrophages. The characterization of the operon genes and their expression profiles in response to infection further contributes to our understanding of the molecular mechanisms of infection and the pathogenesis of brucellosis.