title: [Purification and properties of an antimicrobial substance from marine Brevibacillus laterosporus Lh-1].
abstract: An antimicrobial substance produced by Brevibacillus laterosporus isolated from the sea sediment was purified and characterized. The antimicrobial substance was purified by ultrafiltration, DEAE-Sepharose Fast flow chromatography, CM-Sepharose Fast flow chromatography and HPLC reversed phase column chromatography, and after the final purification step, one active fraction was obtained, designated R-1. The molecular weight (MW) was accurately determined by MALDI-TOF-MS as 1608.023 Da. And its pI was determined with Rotofor Cell BIO-RAD to be 8.55. Amino acid analysis of the purified R-1 showed that it was composed of Leu, Tyr, Val, Ile, Lys, Gly, Met, Ser and Ala. Most of them were hydrophobic and neutral amino acid except Lys which was a basic amino acid. And this accorded with pI of R-1. R-1 remained active over a wide temperature range and it also was active over a broad pH rang. R-1 was insusceptible to pancreatin, pepsin and alkaline proteinase. Agar radial diffusion assay showed that R-1 had low minimun bactericidal concentration against Gram-Positive Bacteria such as Streptococcus mutans, Staphylococcus aureaus, Clostridium and Gram- egative Bacteria such as Escherichia coli Pseudomonas putrefaciens And R-1 had antibacterial activities against Candida albicans
authors.affiliation: Laboratory of Marine Enzyme and Enzyme Engineering, Yellow Sea Fisheries Research Institute, Qingdao 266071, China. zzren1012@126.com
authors.forename: Zhao-Zhen
authors.initials: ZZ
authors.lastname: Ren
authors.forename: Yuan
authors.initials: Y
authors.lastname: Zheng
authors.forename: Mi
authors.initials: M
authors.lastname: Sun
authors.forename: Jun-Zhong
authors.initials: JZ
authors.lastname: Liu
authors.forename: Yue-Jun
authors.initials: YJ
authors.lastname: Wang
mesh_terms: D000890:Anti-Infective Agents / Q000302:isolation & purification* / Q000494:pharmacology; D001951:Brevibacterium / Q000378:metabolism*; D002851:Chromatography, High Pressure Liquid; D019015:Geologic Sediments / Q000382:microbiology*; D006863:Hydrogen-Ion Concentration; D007526:Isoelectric Point; D012623:Seawater / Q000382:microbiology*; D013696:Temperature
chemical_list: D000890:Anti-Infective Agents