A homologue of cytR is essential for initiation of biofilm formation in Pectobacterium carotovorum subsp. carotovorum

摘要

cytR is known as transcriptional repressor of nucleoside uptake and catabolism in Escherichia coli, Salmonella typhimurium and Vibrio cholerae. It was observed that AcytR mutant of Pectobacterium carotovorum subsp. carotovorum which was reported to bea flagellated and non-motile failed to produce biofilm on the surfaces of the wells of polyvinyl chloride (PVC) microtiter plates. The inability of the mutant to initiate biofilm formation on PVC surfaces was further confirmed with phase contrast microscopy. In order to consider the possibility that AcytR mutant failed to produce biofilm due to lack of motility, a non-motile, non-flagellated flhD::Tn5 (flagellar master operon) mutant was tested and it was observed that/Z/jD::Tn5 mutant reduced its ability to form biofilm on PVC surfaces. These results together suggest that inability of AcytR mutant to form biofilm on PVC surfaces was due to loss of motility at least in part. Thus it can be concluded that cytR homologue of P. carotovorum subsp. carotovorum plays an important role in initiation of biofilm formation.