Cloning of Clostridium cellulovorans endo-1,4-beta-glucanase genes.
A Clostridium cellulovorans lambda gt11 gene bank was screened for endo-1,4-beta-glucanase [EC 3.2.1.4, EGase, Carboxy Methyl Cellulase (CMCase)] genes using a chromogenic substrate. Three genes (engA, engB, and engC) were isolated. The engB expressed the most active CMCase. The engA encoded a bifunctional enzyme that displayed endo-1,4-beta-glucanase and beta-glucosidase activities. The three recombinant glucanases, when expressed in Escherichia coli, were partially degraded into multiform active enzymes as evidenced by their SDS-PAGE-CMC zymograms. None of the clones could degrade crystalline cellulose, thus supporting the hypothesis that the integrity of the C. cellulovorans cellulase complex was essential for its 'true cellulase' activity.
Shoseyov
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O
Department of Biochemistry and Biophysics, University of California, Davis 95616.
Hamamoto
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T
Foong
F
F
Doi
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RH
D002480:Cellulase / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism; D003001:Cloning, Molecular / Q000379:methods; D003013:Clostridium / Q000201:enzymology / Q000235:genetics*; D005798:Genes, Bacterial; D005810:Multigene Family; D011994:Recombinant Proteins / Q000302:isolation & purification / Q000378:metabolism; D015183:Restriction Mapping; D001617:beta-Glucosidase / Q000235:genetics / Q000378:metabolism
D011994:Recombinant Proteins; D001617:beta-Glucosidase; D002480:Cellulase