Biology and Medicine

Physiological functions of the CreBC two-component regulatory system in Stenotrophomonas maltophilia

2^nd World Congress on Beneficial Microbes: Food, Pharma, Aqua & Beverages Industry

September 22-24, 2016 Phoenix, USA

Tsuey-Ching Yang, Hsin-Hui Huang and Wei-Ching Chen

National Yang-Ming University, Taiwan
Super Laboratory Co. Ltd., Taiwan

Posters & Accepted Abstracts: Biol Med (Aligarh)

Abstract:

Stenotrophomonas maltophilia occurs naturally in a variety of habitats and harbors at least 43 sets of two-component regulatory systems (TCSs) to respond environmental conditions. The CreBC TCS is a conserved regulatory system found in Escherichia coli, Aeromonas spp., Pseudomonas aeruginosa and S. maltophilia. The physiologic roles of CreBC TCS in bacterial growth, morphology, secreted protease activity and swimming were assessed. We constructed creB, creC and creBC in-frame deletion mutants KJÎ?CreB, KJÎ?CreC and KJÎ?BC in S. maltophilia KJ and compared the behaviors of wild type and mutant strains in a variety of assays. Single knockout mutants KJÎ?CreB or KJÎ?CreC and the double mutant (KJÎ?BC) displayed wild type patterns of growth and morphology. Compared to that in wild-type KJ, secreted protease activity in KJÎ?CreB was unchanged; however, secreted protease activity was significantly reduced in KJÎ?CreC and KJÎ?BC. This finding suggested that CreC can be cognate with an unidentified response regulator and governs secreted protease activity. Single gene inactivation of either creB or creC in S. maltophilia KJ resulted in mutants with enhanced swimming motility and this phenotype was augmented in the double mutant KJÎ?BC. To elucidate the underlying regulatory circuit responsible for Î?creBC-mediated swimming enhancement, morphological observation of the flagella was performed. Most KJÎ?BC cells had flagella numbers and morphology similar to those of wild-type KJ cells, ruling out the possibility that enhanced swimming motility in KJÎ?BC was due to altered flagella morphology. The exact mechanism responsible for the Î?creBC-mediated swimming enhancement is still unclear.

Biography :

Tsuey-Ching Yang is a Professor of National Yang-Ming University, Taiwan. She has published more than 50 papers in reputed journals.

Email: tcyang@ym.edu.tw