title: The biotechnological potential of subtilisin-like fibrinolytic enzyme from a newly isolated Lactobacillus plantarum KSK-II in blood destaining and antimicrobials.
abstract: An antimicrobial oxidative- and SDS-stable fibrinolytic alkaline protease designated as KSK-II was produced by Lactobacillus plantarum KSK-II isolated from kishk, a traditional Egyptian food. Maximum enzyme productivity was obtained in medium containing 1% lactose and 0.5% soybean flour as carbon and nitrogen sources, respectively. Purification of enzyme increased its specific activity to 1,140-fold with a recovery of 33% and molecular weight of 43.6 kDa. Enzyme activity was totally lost in the presence of ethylenediaminetetraacetic acid and was restored after addition of Fe(2+) suggesting that KSK-II is a metalloprotease and Fe(2+) acts as cofactor. Enzyme hydrolyzed not only the natural proteins but also synthetic substrates, particularly Suc-Ala-Ala-Pro-Phe-pNA. KSK-II can hydrolyze the Lys-X easier than Arg-X; thus, it was considered as a subtilisin-family protease. Its apparent Km , Vmax , and Kcat were 0.41 mM, 6.4 µmol mg(-1) min(-1) , and 28.0 s(-1) , respectively. KSK-II is industrially important from the perspectives of its maximal activity at 50°C (stable up to 70°C), ability to function at alkaline pH (10.0), stability at broad pH ranges (7.5-12.0) in addition to its stability toward SDS, H2 O2 , organic solvents, and detergents. We emphasize for the first time the potential of fibrinolytic activity for alkaline proteases used in detergents especially in blood destaining.
authors.affiliation: Research Laboratory of Bacteriology, Dept. of Microbiology, Faculty of Science, Zagazig University, Zagazig, Egypt, 44519.
authors.forename: Essam
authors.initials: E
authors.lastname: Kotb
mesh_terms: D000890:Anti-Infective Agents / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism / Q000494:pharmacology; D001419:Bacteria / Q000187:drug effects; D001426:Bacterial Proteins / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism / Q000494:pharmacology; D001709:Biotechnology; D001769:Blood / Q000187:drug effects; D003902:Detergents / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism / Q000494:pharmacology; D010450:Endopeptidases / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism / Q000494:pharmacology; D004795:Enzyme Stability; D006801:Humans; D048191:Lactiplantibacillus plantarum / Q000201:enzymology* / Q000378:metabolism; D020860:Subtilisin; D013696:Temperature
chemical_list: D000890:Anti-Infective Agents; D001426:Bacterial Proteins; D003902:Detergents; D010450:Endopeptidases; D020860:Subtilisin; C087822:alkaline protease
keywords: L. plantarum; alkaline proteases; blood destaining; fermented foods; fibrinolytic enzymes