[Biodegradation of triphenyltin and its effect on Klebsiella pneumoniae]

To investigate the pathway and mechanism of triphenyltin (TPhT) biodegradation by Klebsiella pneumoniae, and the effects of TPhT on cells during the degradation process, the alteration of carbon utilization ability of the strain after dealing with different concentrations of TPhT was studied by the Biolog method, and the degradation pathway of TPhT was explored by GC-MS and X-ray photoelectron spectroscopy (XPS). After degradation for 2 h, the nutrient utilization capacity of K. pneumoniae was significantly improved by 1 mg x L(-1) TPhT. Atomic force microscope observation found that exposure to TPhT changed the cellular morphology, inducing the apoptosis of some cells, but most of the cells still maintained intact and had smooth cell wall. The efficiencies of TPhT removal by intracellular enzyme were up to 66.0% within 120 h, which demonstrated that endoenzyme was more effective than the intact cells. The results of GC-MS and XPS revealed that during the biodegradation process, TPhT was transformed to diphenyltin, monophenyltin and finally inorganic tin.