Construction and Analysis of a MutL Knockout Strain of Vibrio cholerae.

摘要

Most bacterial species contain a DNA mismatch repair system. In E. coli, the products of mutS, mutL, and mutH, among others, reduce the rate at which mismatch mutations occur, as well as reduce the incorporation of foreign DNA into the E. coli genome (Townsend. 2003). The absence or disruption of these genes increases the background mutation rate (Taddel, 1997). In this study, we describe the construction of a mutL deletion mutant of Vibrio cholerae. This knockout strain will be used to determine the contribution of methyl-directed DNA mismatch repair in conferring antibiotic resistance in V. cholerae. If the knockout of mutL produces a hypervariable strain of V. cholerae, the strain may also be useful in conducting directed evolution experiments at an accelerated pace. The population of V. cholerae mutants obtained in such studies may change the way targets for detection, identification, or even vaccines are chosen.