%0 Journal Article %A McLaughlan, Anna M. %A Foster, Simon J. %T Molecular characterization of an autolytic amidase of Listeria monocytogenes EGD %D 1998 %J Microbiology, %V 144 %N 5 %P 1359-1367 %@ 1465-2080 %R https://doi.org/10.1099/00221287-144-5-1359 %K peptidoglycan hydrolase %K autolysin %K amidase %K Listeria monocytogenes %I Microbiology Society, %X The gene encoding a 102 kDa autolysin has been cloned from an expression library of Listeria monocytogenes EGD genomic DNA, using a direct screening protocol. The encoded protein has two domains, an N-terminal enzymic domain showing a high level of homology to the amidase domain of the major autolysin (atl) of Staphylococcus aureus, and a C-terminal, putative cell-wall-binding domain containing four imperfect direct repeats. In order to examine the role of the enzyme, the autolysin-encoding gene was insertionally inactivated by site-specific integration of a temperature sensitive plasmid. The enzyme accounts for 66% of the total lytic enzyme activity when L. monocytogenes walls are used as substrate and several of the major autolytic bands are missing on renaturing gels when compared to the wild-type. The enzyme does not appear to be directly involved in cell separation but has a role in motility. Characterization of the recombinant enzyme expressed in Escherichia coli has revealed it to be an amidase and to be able to hydrolyse a range of peptidoglycan substrates. %U https://www.microbiologyresearch.org/content/journal/micro/10.1099/00221287-144-5-1359