Characterization of endolysin from a Salmonella Typhimurium-infecting bacteriophage SPN1S

• Published in: Research in microbiology Vol. 163; no. 3; pp. 233 - 241
• Main Authors: Lim, Jeong-A., Shin, Hakdong, Kang, Dong-Hyun, Ryu, Sangryeol
• Format: Journal Article
• Language: English
• Published: Issy-les-Moulineaux Elsevier Masson SAS 01.04.2012; Elsevier Masson
• Subjects: Animals; Bacteriology; Bacteriolysis; Bacteriophage; Biological and medical sciences; Chickens; Chromatography, Affinity; DNA, Viral - chemistry; DNA, Viral - genetics; Endolysin; Endopeptidases - chemistry; Endopeptidases - genetics; Endopeptidases - isolation & purification; Endopeptidases - metabolism; Enzyme Stability; Escherichia coli - genetics; Fundamental and applied biological sciences. Psychology; Gene Expression; Genome, Viral; Gram-Negative Bacteria - drug effects; Gram-Negative Bacteria - physiology; Gram-Positive Bacteria - drug effects; Gram-Positive Bacteria - physiology; Hydrogen-Ion Concentration; Microbial Viability - drug effects; Microbiology; Miscellaneous; Molecular Sequence Data; Peptidoglycan hydrolase; Recombinant Fusion Proteins - chemistry; Recombinant Fusion Proteins - genetics; Recombinant Fusion Proteins - isolation & purification; Recombinant Fusion Proteins - metabolism; Salmonella Phages - enzymology; Salmonella Phages - genetics; Salmonella Phages - isolation & purification; Salmonella Typhimurium; Salmonella typhimurium - isolation & purification; Salmonella typhimurium - virology; Sequence Analysis, DNA; Temperature; Virology; Endolysin; Peptidoglycan hydrolase; Bacteriophage; Salmonella Typhimurium; Virus; Peptidoglycan; Enzyme; Bacteria; Hydrolases; Salmonella typhimurium; Enterobacteriaceae; Phage
• DOI: 10.1016/j.resmic.2012.01.002
• ISSN: 0923-2508

The full genome sequence of bacteriophage SPN1S, which infects Salmonella, contains genes that encode homologues of holin, endolysin and Rz/Rz1-like accessory proteins, which are 4 phage lysis proteins. The ability of these proteins to lyse Escherichia coli cells when overexpressed was evaluated. In contrast to other endolysins, the expression of endolysin and Rz/Rz1-like proteins was sufficient to cause lysis. The endolysin was tagged with oligohistidine at the N-terminus and purified by affinity chromatography. The endolysin has a lysozyme-like superfamily domain, and its activity was much stronger than that of lysozyme from chicken egg white. We used the chelating agent, ethylenediaminetetraacetic acid (EDTA), to increase outer membrane permeability, and it greatly enhanced the lytic activity of SPN1S endolysin. The antimicrobial activity of endolysin was stable over broad pH and temperature ranges and was active from pH 7.0 to 10.5 and from 25 °C to 45 °C. The SPN1S endolysin could kill most of the tested Gram-negative strains, but the Gram-positive strains were resistant. SPN1S endolysin, like lysozyme, cleaves the glycosidic bond of peptidoglycan. These results suggested that SPN1S endolysin has potential as a therapeutic agent against Gram-negative bacteria.