Preliminary study on the role of novel LysR family gene kp05372 in Klebsiella pneumoniae of forest musk deer

AbstractLysR-type transcriptional regulators are involved in the regulation of numerous cellular metabolic processes inKlebsiella pneumoniae, leading to severe infection. Earlier, we found a novel LysR family gene, namedkp05372, in a strain ofK. pneumoniae (designated GPKP) isolated from forest musk deer. To study the function of this gene in relation to the biological characteristics of GPKP, we used the suicide plasmid and conjugative transfer methods to construct deletion mutant strain GPKP- Δkp05372; moreover, we also constructed the GPKP- Δkp05372+ complemented strain. The role of this gene was determined by comparing the following characteristics of three strains: growth curves, biofilm formation, drug resistance, stress resistance, median lethal dose (LD50), organ colonization ability, and the histopathology of GPKP. Real-time polymerase chain reaction (RT-PCR) was used to test the expression level of seven genes upstream ofkp05372. There was no significant difference in the growth rates when comparing the three bacterial strains, and no significant difference was recorded at different osmotic pressures, temperatures, salt contents, or hydrogen peroxide concentrations. The GPKP- Δkp05372 mutant formed a weak biofilm, and the other two strains formed medium biofilm. The drug resistance of the GPKP- Δkp05372 mutant toward cephalothin, cotrimoxazole, and polymyxin B was changed. The acid tolerance of the deletion strain was strongerthan that of the othertwo strains. T...
Source: Journal of Zhejiang University. Science. B. - Category: Universities & Medical Training Source Type: research