title: Characterization of antimicrobial lipopeptides produced by Bacillus sp. LM7 isolated from chungkookjang, a Korean traditional fermented soybean food.
abstract: A wild-type microorganism exhibiting antimicrobial activities was isolated from the Korean traditional fermented soybean food Chungkookjang and identified as Bacillus sp. LM7. During its stationary growth phase, the microorganism secreted an antimicrobial substance, which we partially purified using a simple two-step procedure involving ammonium sulfate precipitation and heat treatment. The partially purified antimicrobial substance, Anti-LM7, was stable over a broad pH range (4.0-9.0) and at temperatures up to 80 °C for 30 min, and was resistant to most proteolytic enzymes and maintained its activity in 30% (v/v) organic solvents. Anti-LM7 inhibited the growth of a broad range of Gram-positive bacteria, including Bacillus cereus and Listeria monocytogenes, but it did not inhibit lactic acid bacteria such as Lactobacillus plantarum and Lactococcus lactis subsp. Lactis. Moreover, unlike commercially available nisin and polymyxin B, Anti-LM7 inhibited certain fungal strains. Lastly, liquid chromatography-mass spectrometry analysis of Anti-LM7 revealed that it contained eight lipopeptides belonging to two families: four bacillomycin D and four surfactin analogs. These Bacillus sp. LM7-produced heterogeneous lipopeptides exhibiting extremely high stability and a broad antimicrobial spectrum are likely to be closely related to the antimicrobial activity of Chungkookjang, and their identification presents an opportunity for application of the peptides in environmental bioremediation, pharmaceutical, cosmetic, and food industries.
authors.affiliation: Bacterial Resources Research Team, Freshwater Bioresources Research Division, Nakdonggang National Institute of Biological Resource, Sangju-si, Gyeongsangbuk-do 37242, Republic of Korea.
authors.forename: Mi-Hwa
authors.initials: MH
authors.lastname: Lee
authors.affiliation: Gut Microbiome Research Group, Korea Food Research Institute, Sungnam, Gyeonggi-Do, 463-746, Republic of Korea.
authors.forename: Jiyeon
authors.initials: J
authors.lastname: Lee
authors.affiliation: Gut Microbiome Research Group, Korea Food Research Institute, Sungnam, Gyeonggi-Do, 463-746, Republic of Korea; Korea University of Science and Technology, Daejeon 305-350, Republic of Korea.
authors.forename: Young-Do
authors.initials: YD
authors.lastname: Nam
authors.affiliation: Biocenter, Gyeonggi Institute of Science & Technology Promotion(GSTEP), Suwon, Gyeonggi-do, 443-270, Republic of Korea.
authors.forename: Jong Suk
authors.initials: JS
authors.lastname: Lee
authors.affiliation: Division of Bioengineering, Incheon National University, Incheon 406-772, Republic of Korea. Electronic address: mjseo@inu.ac.kr.
authors.forename: Myung-Ji
authors.initials: MJ
authors.lastname: Seo
authors.affiliation: Korea Food Research Institute, Sungnam, Gyeonggi-Do, 463-746, Republic of Korea. Electronic address: sunghunyi@kfri.re.kr.
authors.forename: Sung-Hun
authors.initials: SH
authors.lastname: Yi
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology; D000890:Anti-Infective Agents / Q000737:chemistry / Q000494:pharmacology; D001407:Bacillus / Q000378:metabolism; D001430:Bacteriocins / Q000737:chemistry / Q000494:pharmacology; D005516:Food Microbiology; D006094:Gram-Positive Bacteria / Q000187:drug effects; D006863:Hydrogen-Ion Concentration; D007529:Isoflavones / Q000737:chemistry*; D055666:Lipopeptides / Q000737:chemistry*; D030262:Soybean Proteins / Q000737:chemistry*; D013025:Glycine max / Q000378:metabolism / Q000382:microbiology; D013696:Temperature
chemical_list: D000900:Anti-Bacterial Agents; D000890:Anti-Infective Agents; D001430:Bacteriocins; D007529:Isoflavones; D055666:Lipopeptides; D030262:Soybean Proteins; C525760:chungkookjang
keywords: Antimicrobial activity; Bacillus; Chungkookjang; Lipopeptide