Sequence analysis of the Clostridium stercorarium celZ gene encoding a thermoactive cellulase (Avicelase I): Identification of catalytic and cellulose-binding domains

Sigrid Jauris, Karl P. Rücknagel, Wolfgang H. Schwarz, Peter Kratzsch, Karin Bronnenmeier, Walter L. Staudenbauer

Research output: Contribution to journalArticlepeer-review

77 Scopus citations

Abstract

The nucleotide sequence of the celZ gene coding for a thermostable endo-β-1,4-glucanase (Avicelase I) of Clostridium stercorarium was determined. The structural gene consists of an open reading frame of 2958 by which encodes a preprotein of 986 amino acids with an Mr of 109000. The signal peptide cleavage site was identified by comparison with the N-terminal amino acid sequence of Avicelase I purified from C. stercorarium culture supernatants. The recombinant protein expressed in Escherichia coli is proteolytically cleaved into catalytic and cellulose-binding fragments of about 50 kDa each. Sequence comparison revealed that the N-terminal half of Avicelase I is closely related to avocado (Persea americana) cellulase. Homology is also observed with Clostridium thermocellum endoglucanase D and Pseudomonas fuorescens cellulase. The cellulose-binding region was located in the C-terminal half of Avicelase I. It consists of a reiterated domain of 88 amino acids flanked by a repeated sequence about 140 amino acids in length. The C-terminal flanking sequence is highly homologous to the non-catalytic domain of Bacillus subtilis endoglucanase and Caldocellum saccharolyticum endoglucanase B. It is proposed that the enhanced cellulolytic activity of Avicelase I is due to the presence of multiple cellulose-binding sites.

Original languageEnglish
Pages (from-to)258-267
Number of pages10
JournalMGG Molecular & General Genetics
Volume223
Issue number2
DOIs
StatePublished - Sep 1990

Keywords

  • Avocado
  • Cellulase
  • Clostridium stercorarium
  • DNA sequence
  • Endoglucanase

Fingerprint

Dive into the research topics of 'Sequence analysis of the Clostridium stercorarium celZ gene encoding a thermoactive cellulase (Avicelase I): Identification of catalytic and cellulose-binding domains'. Together they form a unique fingerprint.

Cite this