Nucleotide sequence of the celA gene encoding a cellodextrinase of Ruminococcus flavefaciens FD-1.
The nucleotide sequence of a 3.6 kb DNA fragment containing a cellodextrinase gene (celA) from Ruminococcus flavefaciens FD-1 was determined. The gene was expressed from its own regulatory region in Escherichia coli and a putative consensus promoter sequence was identified upstream of a ribosome binding site and a TTG start codon. The complete amino acid sequence of the CelA enzyme (352 residues) was deduced and showed no significant homology to cellulases from other organisms. Two lysozyme-type active sites were found in the amino-terminal third of the enzyme. In E. coli the cloned Cel A protein was translocated into the periplasm. The lack of a typical signal sequence, and the results of transposon phoA mutagenesis experiments indicated that CelA is secreted by a mechanism other than a leader peptide.
Wang
W Y
WY
Department of Microbiology, University of Cape Town, Rondebosch, South Africa.
Thomson
J A
JA
D000595:Amino Acid Sequence; D001483:Base Sequence; D002266:Carboxymethylcellulose Sodium / Q000378:metabolism; D002480:Cellulase / Q000378:metabolism*; D003001:Cloning, Molecular; D004269:DNA, Bacterial; D004591:Electrophoresis, Polyacrylamide Gel; D005798:Genes, Bacterial; D008969:Molecular Sequence Data; D010459:Peptococcaceae / Q000201:enzymology / Q000235:genetics*; D011401:Promoter Regions, Genetic; D012270:Ribosomes / Q000378:metabolism; D012689:Sequence Homology, Nucleic Acid
D004269:DNA, Bacterial; D002480:Cellulase; D002266:Carboxymethylcellulose Sodium