Bioscience, Biotechnology, and Biochemistry
Online ISSN : 1347-6947
Print ISSN : 0916-8451
Microbiology & Fermentation Technology Regular Papers
Deduced Amino Acid Sequence and Possible Catalytic Residues of a Thermostable, Alkaline Cellulase from an Alkaliphilic Bacillus Strain
Yoshihiro HAKAMADAYuji HATADAKenzo KOIKETadashi YOSHIMATSUShuji KAWAITohru KOBAYASHISusumu ITO
Author information
JOURNALS FREE ACCESS

2000 Volume 64 Issue 11 Pages 2281-2289

Details
Abstract

  Alkaliphilic Bacillus sp. strain KSM-S237 (a relative of Bacillus pseudofirmus) produces a thermostable, alkaline endo-1,4-β-glucanase (Egl). The entire gene for the enzyme harbored a 2,472-bp open reading frame (ORF) encoding 824 amino acids, including a 30-amino-acid signal peptide. The deduced amino acid sequence of the mature enzyme (794 amino acids, 88,284 Da) showed very high similarity to those of family 5 mesophilic, alkaline Egls from some alkaliphilic bacilli. The enzyme had a region similar to a novel cellulose binding domain proposed for an Egl (EngF) from Clostridium cellulovorans. Expression of the Bacillus Egl gene in Bacillus subtilis resulted in high carboxymethy cellulase activity (2.0 g/l) in the culture broth, concomitant with the appearance of a protein band on an SDS gel at 86 kDa. Site-directed mutagenesis delineated the importance of Arg111, His151, Glu190, His262, Tyr264, and Glu305 in catalysis and/or substrate binding of the enzyme.

Information related to the author

This article cannot obtain the latest cited-by information.

© 2000 by Japan Society for Bioscience, Biotechnology, and Agrochemistry
Previous article Next article
feedback
Top