title: Production of recombinant Bacillus subtilis chitosanase, suitable for biosynthesis of chitosan-oligosaccharides.
abstract: Chitosanases are enzymes that catalyse the hydrolysis of the β-1,4 glycosidic bond of chitosan. One of the most promising applications of this enzyme is for the bioconversion of chitosan into value-added chitosan-oligosaccharides (COS). GH46 chitosanase (Csn) from Bacillus subtilis 168 was expressed in Escherichia coli by fusing the gene encoding mature Csn to the E. coli OmpA signal peptide sequence. The recombinant enzyme was secreted into the culture supernatant. The recombinant Csn showed high specific activity and stability over a wide range of pH. The enzyme was >100 times more thermostable in the presence of the substrate, with a half-life time of activity (τ(1/2)) of approximately 20 h at 50 °C and pH 5.5. Efficient bioconversion of chitosan into different mixtures of COS, using crude culture supernatant containing secreted enzyme was demonstrated.
authors.affiliation: Molecular Biotechnology Laboratory, School of Biotechnology, Institute of Agricultural Technology, Suranaree University of Technology, Nakhon Ratchasima, Thailand.
authors.forename: Phornsiri
authors.initials: P
authors.lastname: Pechsrichuang
authors.forename: Kirana
authors.initials: K
authors.lastname: Yoohat
authors.forename: Montarop
authors.initials: M
authors.lastname: Yamabhai
mesh_terms: D000595:Amino Acid Sequence; D001412:Bacillus subtilis / Q000201:enzymology*; D001483:Base Sequence; D001709:Biotechnology / Q000379:methods*; D048271:Chitosan / Q000737:chemistry; D002855:Chromatography, Thin Layer; D003001:Cloning, Molecular; D019295:Computational Biology; D017931:DNA Primers / Q000235:genetics; D004591:Electrophoresis, Polyacrylamide Gel; D004926:Escherichia coli; D006026:Glycoside Hydrolases / Q000235:genetics* / Q000378:metabolism*; D006207:Half-Life; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008969:Molecular Sequence Data; D009844:Oligosaccharides / Q000096:biosynthesis* / Q000737:chemistry; D017422:Sequence Analysis, DNA; D013696:Temperature
chemical_list: D017931:DNA Primers; D009844:Oligosaccharides; D048271:Chitosan; D006026:Glycoside Hydrolases; C019868:chitosanase