Biofilm Physiology and Cyclic-di-GMP in Escherichia coli.

摘要

Biofilm formation can occur in response to external cues, and affords bacteria living in these communities enhanced survival to antimicrobials and other stressors, compared to their free-swimming counterparts. The transition from a motile to biofilm lifestyle appears to be controlled by the bacterial messenger, cyclic-di-GMP; which is synthesized and degraded by cyclic-di-GMP metabolizing proteins. The activity of these proteins has been implicated in the regulation of biofilm-associated phenotypes; however, the physiological functions of the majority of these proteins remain unknown. In this thesis, we examined the role of genes encoding for cyclic-di-GMP metabolizing proteins in the formation and antimicrobial susceptibility of Escherichia coli biofilms. We found that deletion of genes that encode for cyclic-di-GMP metabolizing proteins does not affect the ability of E. coli to form biofilms. Furthermore, we discovered that a subset of these genes may contribute to the resistance mechanisms of biofilms to antimicrobial stress.