Expression of chitinases in Listeria monocytogenes is influenced by lmo0327 that encodes an internalin-like protein.

Expression of chitinases in Listeria monocytogenes is influenced by lmo0327 that encodes an internalin-like protein. Appl Environ Microbiol. 2017 Sep 08;: Authors: Paspaliari DK, Kastbjerg VG, Ingmer H, Popowska M, Larsen MH Abstract The chitinolytic system of Listeria monocytogenes thus far comprises two chitinases, ChiA and ChiB, and a lytic polysaccharide monooxygenase, Lmo2467. The role of the system in the bacterium appears to be pleiotropic, as besides mediating hydrolysis of chitin, the second most ubiquitous carbohydrate in nature, the chitinases have been deemed important for colonization of unicellular moulds, as well as mammalian hosts. In order to identify additional components of the chitinolytic system, we screened a transposon mutant library for mutants exhibiting impaired chitin hydrolysis. The screening yielded a mutant with a transposon insertion in a locus corresponding to lmo0327 of the EGD-e strain. lmo0327 encodes a large (1349 aa) cell-wall associated protein that has been proposed to possess murein hydrolase activity. Single inactivation of lmo0327, as well as of lmo0325 that codes for a putative transcriptional regulator functionally related to lmo0327, led to an almost complete abolishment of chitinolytic activity. The effect could be traced at the transcriptional level, as both chiA and chiB transcripts were dramatically decreased in the lmo0327 mutant. In accordance with that, we could barely detect ChiA a...
Source: Applied and Environmental Microbiology - Category: Microbiology Authors: Tags: Appl Environ Microbiol Source Type: research