Chitobiose production by using a novel thermostable chitinase from Bacillus licheniformis strain JS isolated from a mushroom bed.
The thermophilic Bacillus licheniformis strain JS was isolated from a bed of mushrooms, Pleurotus sajor-caju. The organism could produce a novel, single-component, thermostable chitinase that was purified by ion-exchange chromatography using DEAE-cellulose in 7.64% yield and in an 8.1-fold enhancement in purity. Its molecular weight is 22kDa. The enzyme is a chitobiosidase, since the chitin hydrolysate is N(I),N(II)-diacetylchitobiose. The optimum temperature for enzyme activity is 55°C, and the optimum pH is 8.0. It was completely inhibited by Hg(2+) ions whereas Co(2+) ions served as an activator. The thermostability of this enzyme is important in the bioconversion of chitinous waste and for the production of chitooligosaccharides.
Waghmare
Shailesh R
SR
Department of Microbiology, Shivaji University, Vidyanagar, Kolhapur 416 004, India.
Ghosh
Jai S
JS
D000363:Agaricales; D001407:Bacillus / Q000201:enzymology*; D002688:Chitinases / Q000302:isolation & purification / Q000378:metabolism*; D002852:Chromatography, Ion Exchange; D004187:Disaccharides / Q000096:biosynthesis*; D004795:Enzyme Stability
D004187:Disaccharides; C032438:chitobiose; D002688:Chitinases