title: The overexpression of the SAPB of Bacillus pumilus CBS and mutated sapB-L31I/T33S/N99Y alkaline proteases in Bacillus subtilis DB430: new attractive properties for the mutant enzyme.
abstract: The sapB gene encoding for Bacillus pumilus CBS protease (SAPB) and the triple mutated sapB-L31I/T33S/N99Y gene were cloned and overexpressed in the protease-deficient Bacillus subtilis DB430 using an Escherichia coli-Bacillus shuttle vector pBSMuL2. The 34,625.13 and 34,675.11-Da enzymes were purified from the culture supernatant of B. subtilis expressing the wild-type and mutated genes, respectively. The purified proteases showed the same N-terminal sequences and biochemical properties of those expressed in E. coli. Further investigations demonstrated that, compared to wild-type and other proteases, SAPB-L31I/T33S/N99Y had the highest catalytic efficiency and the best degree of hydrolysis. The mutant enzyme was also noted to exhibit a number of newly explored properties that are highly valued in the marketplace, namely considerable stability to detergents, higher resistance towards organic solvents, and potent dehairing ability. Overall, the findings indicated that SAPB-L31I/T33S/N99Y is a promising candidate for future use in a wide range of industrial and commercial applications.
authors.affiliation: Laboratory of Microorganisms and Biomolecules (LMB), Centre of Biotechnology of Sfax (CBS), University of Sfax, Road of Sidi Mansour Km 6, P.O. Box 1177, 3018 Sfax, Tunisia.
authors.forename: Nadia Zaraî
authors.initials: NZ
authors.lastname: Jaouadi
authors.forename: Bassem
authors.initials: B
authors.lastname: Jaouadi
authors.forename: Nushin
authors.initials: N
authors.lastname: Aghajari
authors.forename: Samir
authors.initials: S
authors.lastname: Bejar
mesh_terms: D001407:Bacillus / Q000235:genetics / Q000378:metabolism*; D001412:Bacillus subtilis / Q000235:genetics / Q000378:metabolism*; D001426:Bacterial Proteins / Q000235:genetics* / Q000378:metabolism; D001709:Biotechnology / Q000379:methods; D003902:Detergents / Q000737:chemistry / Q000494:pharmacology; D010450:Endopeptidases / Q000235:genetics* / Q000378:metabolism; D004926:Escherichia coli / Q000378:metabolism; D015964:Gene Expression Regulation, Bacterial; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D007220:Industrial Waste; D007700:Kinetics; D009154:Mutation; D010957:Plasmids / Q000378:metabolism; D017434:Protein Structure, Tertiary; D012492:Salts / Q000737:chemistry; D012997:Solvents / Q000737:chemistry; D013379:Substrate Specificity; D013633:Tanning; D013696:Temperature
chemical_list: D001426:Bacterial Proteins; D003902:Detergents; D007220:Industrial Waste; D012492:Salts; D012997:Solvents; D010450:Endopeptidases; C087822:alkaline protease