Characterization, cloning and sequencing of a thermostable endo-(1,3-1,4) beta-glucanase-encoding gene from an alkalophilic Bacillus brevis.
A Bacillus brevis gene coding for an endo-(1,3-1,4)-beta-glucanase was cloned in Escherichia coli and sequenced. The open reading frame contains a sequence of 759 nucleotides encoding a polypeptide of 252 amino acid residues. The amino acid sequence of the beta-glucanase gene showed only a 50% similarity to previously published data for Bacillus endo-(1,3-1,4)-beta-glucanases. The optimum temperature and pH for enzyme activity were 65-70 degrees C and 8-10, respectively. When held at 75 degrees C for 1 h, 75% residual activity was measured. The molecular mass was estimated to be about 29 kDa on sodium dodecyl sulphate (SDS)-polyacrylamide gel electrophoresis and the enzyme was found to be resistant to SDS.
Louw
M E
ME
Biotechnology Programme, CSIR, Pretoria, Republic of South Africa.
Reid
S J
SJ
Watson
T G
TG
D000595:Amino Acid Sequence; D001407:Bacillus / Q000201:enzymology* / Q000235:genetics / Q000302:isolation & purification; D003001:Cloning, Molecular; D004269:DNA, Bacterial; D004591:Electrophoresis, Polyacrylamide Gel; D004795:Enzyme Stability; D004926:Escherichia coli; D005798:Genes, Bacterial; D006026:Glycoside Hydrolases / Q000235:genetics* / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D008969:Molecular Sequence Data; D016415:Sequence Alignment; D013379:Substrate Specificity; D013696:Temperature
D004269:DNA, Bacterial; D006026:Glycoside Hydrolases; C028020:licheninase