Expression in Escherichia coli of the Cellulomonas fimi Structural Gene for Endoglucanase B

Owolabi, Joshua B. and Beguin, Pierre and Kilburn, Douglas G. and Miller, Robert C. and Warren, R. Anthony J. (1988) Expression in Escherichia coli of the Cellulomonas fimi Structural Gene for Endoglucanase B. APPLIED AND ENVIRONMENTAL MICROBIOLOGY, 54 (2). pp. 518-523.

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Abstract

Endoglucanase B (EB) of Cellulomonasfimi has an Mr of 110,000 when it is produced in Escherichia coli. The level of expression of the cenB gene (encoding EB) was significantly increased by replacing its normal transcriptional and translational regulatory signals with those of the E. coli lac operon. EB was purified to homogeneity from the periplasmic fraction of E. coli in one step by affinity chromatography on microcrystalline cellulose (Avicel). Alignment of the NH2-terminal amino acid sequence with the partial nucleotide sequence of a fragment of C. fimi DNA showed that EB is preceded by a putative signal polypeptide of 33 amino acids. The signal peptide functions and is processed correctly in E. coli, even when its first 15 amino acids are replaced by the first 7 amino acids of 0-galactosidase. The intact EB polypeptide is not required for enzymatic activity. Active polypeptides with Mrs of 95,000 and 82,000 also appear in E. coli, and a deletion mutant of cenB encodes an active polypeptide with an M, of 72,000.

Item Type:	Article
Subjects:	Q Science > QH Natural history > QH301 Biology R Medicine > R Medicine (General)
Divisions:	Faculty of Medicine, Health and Life Sciences > School of Biological Sciences
Depositing User:	Mrs Patricia Nwokealisi
Date Deposited:	16 Oct 2014 09:11
Last Modified:	16 Oct 2014 09:11
URI:	http://eprints.covenantuniversity.edu.ng/id/eprint/2838

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