Molecular cloning and characterization of a chitosanase from the chitosanolytic bacterium Burkholderia gladioli strain CHB101.
A chitosanase was purified from the culture fluid of the chitino- and chitosanolytic bacterium Burkholderia gladioli strain CHB101. The purified enzyme (chitosanase A) had a molecular mass of 28 kDa, and catalyzed the endo-type cleavage of chitosans having a low degree of acetylation (0-30%). The enzyme hydrolyzed glucosamine oligomers larger than a pentamer, but did not exhibit any activity toward N-acetylglucosamine oligomers and colloidal chitin. The gene coding for chitosanase A (csnA) was isolated and its nucleotide sequence determined. B. gladioli csnA has an ORF encoding a polypeptide of 355 amino acid residues. Analysis of the N-terminal amino acid sequence of the purified chitosanase A and comparison with that deduced from the csnA ORF suggests post-translational processing of a putative signal peptide and a possible substrate-binding domain. The deduced amino acid sequence corresponding to the mature protein showed 80% similarity to the sequences reported from Bacillus circulans strain MH-K1 and Bacillus ehimensis strain EAG1, which belong to family 46 glycosyl hydrolases.
Shimosaka
M
M
Department of Applied Biology, Faculty of Textile Science and Technology, Shinshu University, Ueda, Nagano, Japan. mashimo@giptc.shinshu-u.ac.jp
Fukumori
Y
Y
Zhang
X Y
XY
He
N J
NJ
Kodaira
R
R
Okazaki
M
M
D000595:Amino Acid Sequence; D001426:Bacterial Proteins; D001483:Base Sequence; D019117:Burkholderia / Q000145:classification / Q000201:enzymology* / Q000235:genetics; D002686:Chitin / Q000031:analogs & derivatives* / Q000378:metabolism*; D048271:Chitosan; D003001:Cloning, Molecular; D005798:Genes, Bacterial; D006026:Glycoside Hydrolases / Q000737:chemistry / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism*; D007700:Kinetics; D008969:Molecular Sequence Data; D016366:Open Reading Frames; D016415:Sequence Alignment; D013379:Substrate Specificity
D001426:Bacterial Proteins; D002686:Chitin; D048271:Chitosan; C418144:CSNA protein, Burkholderia gladioli; D006026:Glycoside Hydrolases; C019868:chitosanase