Open AccessCell wall substrate specificity of six different lysozymes and lysozyme inhibitory activity of bacterial extracts
Author(s) -
Nakimbugwe Dorothy,
Masschalck Barbara,
Deckers Daphne,
Callewaert Lien,
Aertsen Abram,
Michiels Chris W.
Publication year - 2006
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/j.1574-6968.2006.00240.x
Subject(s) - lysozyme , peptidoglycan , cell wall , egg white , bacterial cell structure , lysis , escherichia coli , bacteria , bacteriophage , micrococcus luteus , biochemistry , biology , microbiology and biotechnology , muramidase , micrococcus , enzyme , chemistry , genetics , gene
We have investigated the specificity of six different lysozymes for peptidoglycan substrates obtained by extraction of a number of gram‐negative bacteria and Micrococcus lysodeikticus with chloroform/Tris‐HCl buffer (chloroform/buffer). The lysozymes included two that are commercially available (hen egg white lysozyme or HEWL, and mutanolysin from Streptomyces globisporus or M1L), and four that were chromatographically purified (bacteriophage λ lysozyme or LaL, bacteriophage T4 lysozyme or T4L, goose egg white lysozyme or GEWL, and cauliflower lysozyme or CFL). HEWL was much more effective on M. lysodeikticus than on any of the gram‐negative cell walls, while the opposite was found for LaL. Also the gram‐negative cell walls showed remarkable differences in susceptibility to the different lysozymes, even for closely related species like Escherichia coli and Salmonella Typhimurium. These differences could not be due to the presence of lysozyme inhibitors such as Ivy from E. coli in the cell wall substrates because we showed that chloroform extraction effectively removed this inhibitor. Interestingly, we found strong inhibitory activity to HEWL in the chloroform/buffer extracts of Salmonella Typhimurium, and to LaL in the extracts of Pseudomonas aeruginosa , suggesting that other lysozyme inhibitors than Ivy exist and are probably widespread in gram‐negative bacteria.