title: Endolysin LysSA97 is synergistic with carvacrol in controlling Staphylococcus aureus in foods.
abstract: LysSA97 is an endolysin encoded by the bacteriophage SA97, the genome sequence of which has been recently revealed. LysSA97 has lytic activity against a variety of Staphylococcus strains that cause foodborne illness. In order to improve its potential as a biocontrol agent against Staphylococcus, various types of essential oil-derived active compounds were tested in combination with LysSA97; carvacrol exhibited significant synergistic effects when combined with LysSA97. The synergistic antimicrobial activity between endolysin and carvacrol in food products, including milk and beef, were investigated. While LysSA97 (376nM) and carvacrol (3.33mM) showed 0.8±0.2 and 1.0±0.0logCFU/mL reduction in Staphylococcus aureus cells, respectively; when applied alone in bacterial culture, the cocktail containing both at the same concentrations exhibited a bacterial decrease of 4.5±0.2logCFU/mL. The synergistic activity of carvacrol was also reproduced in combination with other endolysins, and their cooperative bactericidal effects were validated in ten additional S. aureus strains, including two methicillin-resistant S. aureus (MRSA), suggesting the wide application of carvacrol as a bactericidal agent coupled with endolysin. When LysSA97 and carvacrol were used in combination in foods, the synergistic activity appeared to be influenced by the total lipid content of foods, and bacteria in skim milk were more drastically inactivated than those in whole milk. Therefore, this is the first report demonstrating that endolysin and carvacrol act synergistically to inactivate S. aureus in food products.
authors.affiliation: Department of Food and Animal Biotechnology, Department of Agricultural Biotechnology, Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul 151-921, Republic of Korea.
authors.forename: Yoonjee
authors.initials: Y
authors.lastname: Chang
authors.affiliation: Department of Molecular Science and Technology, Department of Applied Chemistry and Biological Engineering, Ajou University, Suwon 16499, Republic of Korea.
authors.forename: Hyunjin
authors.initials: H
authors.lastname: Yoon
authors.affiliation: Department of Food and Animal Biotechnology, Department of Agricultural Biotechnology, Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul 151-921, Republic of Korea; Center for Food and Bioconvergence, Seoul National University, Seoul 151-742, Republic of Korea; Institute of Food Industrialization, Institutes of Green Bio Science and Technology, Seoul National University, Pyeongchang, Gangwon 232-916, Republic of Korea.
authors.forename: Dong-Hyun
authors.initials: DH
authors.lastname: Kang
authors.affiliation: Department of Food and Animal Biotechnology, Department of Agricultural Biotechnology, Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul 151-921, Republic of Korea; Center for Food and Bioconvergence, Seoul National University, Seoul 151-742, Republic of Korea.
authors.forename: Pahn-Shick
authors.initials: PS
authors.lastname: Chang
authors.affiliation: Department of Food and Animal Biotechnology, Department of Agricultural Biotechnology, Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul 151-921, Republic of Korea; Center for Food and Bioconvergence, Seoul National University, Seoul 151-742, Republic of Korea; Institute of Food Industrialization, Institutes of Green Bio Science and Technology, Seoul National University, Pyeongchang, Gangwon 232-916, Republic of Korea. Electronic address: sangryu@snu.ac.kr.
authors.forename: Sangryeol
authors.initials: S
authors.lastname: Ryu
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001435:Bacteriophages / Q000235:genetics; D061046:Biological Control Agents / Q000494:pharmacology*; D002417:Cattle; D000081007:Cymenes; D004357:Drug Synergism; D010450:Endopeptidases / Q000494:pharmacology*; D005516:Food Microbiology; D005517:Foodborne Diseases / Q000517:prevention & control*; D008460:Meat / Q000382:microbiology; D055624:Methicillin-Resistant Staphylococcus aureus / Q000187:drug effects*; D008826:Microbial Sensitivity Tests; D008892:Milk / Q000382:microbiology; D039821:Monoterpenes / Q000494:pharmacology*; D013203:Staphylococcal Infections / Q000382:microbiology / Q000517:prevention & control*
chemical_list: D000900:Anti-Bacterial Agents; D061046:Biological Control Agents; D000081007:Cymenes; D039821:Monoterpenes; C073316:carvacrol; D010450:Endopeptidases; C001143:endolysin
keywords: Carvacrol; Endolysin; Staphylococcus aureus; Synergistic effect