title: A novel detergent-stable solvent-tolerant serine thiol alkaline protease from Streptomyces koyangensis TN650.
abstract: An alkaline proteinase (STAP) was produced from strain TN650 isolated from a Tunisian off-shore oil field and assigned as Streptomyces koyangensis strain TN650 based on physiological and biochemical properties and 16S rRNA gene sequencing. Matrix assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF/MS) analysis revealed that the purified enzyme was a monomer with a molecular mass of 45125.17-Da. The enzyme had an NH2-terminal sequence of TQSNPPSWGLDRIDQTTAFTKACSIKY, thus sharing high homology with those of Streptomyces proteases. The results showed that this protease was completely inhibited by phenylmethanesulfonyl fluoride (PMSF), diiodopropyl fluorophosphates (DFP), and partially inhibited by 5,5-dithio-bis-(2-nitro benzoic acid) (DTNB), which strongly suggested its belonging to the serine thiol protease family. Using casein as a substrate, the optimum pH and temperature values for protease activity were pH 10 and 70 °C, respectively. The protease was stable at pH 7-10 and 30-60 °C for 24 h. STAP exhibited high catalytic efficiency, significant detergent stability, and elevated organic solvent resistance compared to the SG-XIV proteases from S. griseus and KERAB from Streptomyces sp. AB1. The stap gene encoding STAP was isolated, and its DNA sequence was determined. These properties make STAP a potential candidate for future application in detergent formulations and non-aqueous peptide biocatalysis.
authors.affiliation: Laboratory of Microbial Biotechnology and Engineering Enzymes (LMBEE), Centre of Biotechnology of Sfax (CBS), University of Sfax, Road of Sidi Mansour Km 6, PO Box 1177, Sfax 3018, Tunisia.
authors.forename: Mouna
authors.initials: M
authors.lastname: Ben Elhoul
authors.affiliation: Laboratory of Microbial Biotechnology and Engineering Enzymes (LMBEE), Centre of Biotechnology of Sfax (CBS), University of Sfax, Road of Sidi Mansour Km 6, PO Box 1177, Sfax 3018, Tunisia.
authors.forename: Nadia
authors.initials: N
authors.lastname: Zaraî Jaouadi
authors.affiliation: Laboratory of Microbial Biotechnology and Engineering Enzymes (LMBEE), Centre of Biotechnology of Sfax (CBS), University of Sfax, Road of Sidi Mansour Km 6, PO Box 1177, Sfax 3018, Tunisia.
authors.forename: Hatem
authors.initials: H
authors.lastname: Rekik
authors.affiliation: Laboratory of Microbial Biotechnology and Engineering Enzymes (LMBEE), Centre of Biotechnology of Sfax (CBS), University of Sfax, Road of Sidi Mansour Km 6, PO Box 1177, Sfax 3018, Tunisia.
authors.forename: Wacim
authors.initials: W
authors.lastname: Bejar
authors.affiliation: Laboratory of Natural Products Chemistry and Biomolecules (LNPCB), University of Blida 1, Road of Soumaâ, PO Box 270, 09000 Blida, Algeria.
authors.forename: Souraya
authors.initials: S
authors.lastname: Boulkour Touioui
authors.affiliation: Laboratory of Microbial Biotechnology and Engineering Enzymes (LMBEE), Centre of Biotechnology of Sfax (CBS), University of Sfax, Road of Sidi Mansour Km 6, PO Box 1177, Sfax 3018, Tunisia.
authors.forename: Maher
authors.initials: M
authors.lastname: Hmidi
authors.affiliation: Laboratory of Natural Products Chemistry and Biomolecules (LNPCB), University of Blida 1, Road of Soumaâ, PO Box 270, 09000 Blida, Algeria; National Centre for Research and Development of Fisheries and Aquaculture (CNRDPA) 11, Bd Amirouche PO Box 67, Bou Ismaïl, 42415 Tipaza, Algeria.
authors.forename: Abdelmalek
authors.initials: A
authors.lastname: Badis
authors.affiliation: Laboratory of Microbial Biotechnology and Engineering Enzymes (LMBEE), Centre of Biotechnology of Sfax (CBS), University of Sfax, Road of Sidi Mansour Km 6, PO Box 1177, Sfax 3018, Tunisia.
authors.forename: Samir
authors.initials: S
authors.lastname: Bejar
authors.affiliation: Laboratory of Microbial Biotechnology and Engineering Enzymes (LMBEE), Centre of Biotechnology of Sfax (CBS), University of Sfax, Road of Sidi Mansour Km 6, PO Box 1177, Sfax 3018, Tunisia. Electronic address: bassem.jaouadi@yahoo.fr.
authors.forename: Bassem
authors.initials: B
authors.lastname: Jaouadi
mesh_terms: D001426:Bacterial Proteins / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism; D003902:Detergents / Q000737:chemistry; D010450:Endopeptidases / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism; D004795:Enzyme Stability; D006868:Hydrolysis; D007700:Kinetics; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D057057:Serine Proteases / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism; D012997:Solvents / Q000737:chemistry; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D013302:Streptomyces / Q000201:enzymology*; D013379:Substrate Specificity; D013696:Temperature
chemical_list: D001426:Bacterial Proteins; D003902:Detergents; D012336:RNA, Ribosomal, 16S; D012997:Solvents; D010450:Endopeptidases; D057057:Serine Proteases; C087822:alkaline protease
keywords: Detergent; Protease; Streptomyces