The Man-PTS subunit ⅡC is responsible for the sensitivity of Listeria monocytogenes to durancin GL.

Abstract

Target cell recognition is an important issue in the realization of bacteriocin's activity. In this report, we provide genetic and biochemical evidence of durancin GL, a new bacteriocin produced by Enterococcus durans 41D, and use ⅡC subunit in the mannose phosphotransferase system (Man‐PTS) of Listeria monocytogenes as target/receptor. First, the L. monocytogenes mutants with Man‐PTS IIC or IID deletion were constructed with the vector pHoss1. Then, the utilization of glucose and mannose and the sensitivity to durancin GL of the mutant strains were investigated. Afterward, the interactions between durancin GL and the subunits of IIC or IID in Man‐PTS of L. monocytogenes were characterized by yeast two‐hybrid system. The results showed that the L. monocytogenes mutants with either IIC or IID deletion were not only resistant to durancin GL, but also their absorption and utilization of glucose and mannose were not disturbed by the presence of durancin GL. Finally, in situ detection of the interaction between durancin GL and Man‐PTS subunits of IIC or IID by yeast two‐hybrid system revealed that there was a strong interaction between durancin GL and Man‐PTS subunit IIC. However, the interaction between durancin GL and Man‐PTS subunit IID was not present or weak. Based on the experimental evidence above, the Man‐PTS subunit IIC is responsible for the sensitivity of L. monocytogenes to bacteriocin durancin GL.