CEL1: a novel cellulose binding protein secreted by Agaricus bisporus during growth on crystalline cellulose.
The cel1 gene of Agaricus bisporus encodes a protein (CEL1) that has an architecture resembling the multi-domain fungal cellulases, although the sequence of its putative catalytic core is not matched by any other in the protein and nucleic acid data bases. The N-terminal half of the putative catalytic domain of CEL1 was expressed in Escherichia coli as a fusion protein with glutathione-S-transferase. The fusion protein was used to raise a CEL1-specific antibody. CEL1 was detected as an extracellular 49.8 kDa protein in A. bisporus cellulose-grown cultures, where it bound strongly to cellulose. CEL1 was neither an endoglucanase, a cellobiohydrolase able to hydrolyze fluorogenic cellobiosides, a beta-glucosidase, a xylanase, nor a cellobiose: quinone oxidoreductase. CEL1 was present in some fractions of culture fluid separated by electrophoresis which released soluble sugars from crystalline cellulose.
Armesilla
A L
AL
Division of Life Sciences, King's College London, London, UK.
Thurston
C F
CF
Yagüe
E
E
D000364:Agaricus / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D000595:Amino Acid Sequence; D000908:Antibodies, Fungal / Q000096:biosynthesis; D001483:Base Sequence; D002352:Carrier Proteins / Q000096:biosynthesis / Q000235:genetics / Q000276:immunology; D002480:Cellulase / Q000096:biosynthesis* / Q000235:genetics / Q000276:immunology; D002482:Cellulose / Q000378:metabolism*; D043366:Cellulose 1,4-beta-Cellobiosidase; D003001:Cloning, Molecular; D004271:DNA, Fungal / Q000235:genetics; D004926:Escherichia coli / Q000235:genetics; D005656:Fungal Proteins / Q000096:biosynthesis* / Q000235:genetics / Q000276:immunology; D005800:Genes, Fungal; D005822:Genetic Vectors; D005982:Glutathione Transferase / Q000096:biosynthesis / Q000235:genetics; D008969:Molecular Sequence Data; D011993:Recombinant Fusion Proteins / Q000096:biosynthesis / Q000235:genetics / Q000276:immunology
D000908:Antibodies, Fungal; D002352:Carrier Proteins; D004271:DNA, Fungal; D005656:Fungal Proteins; D011993:Recombinant Fusion Proteins; D002482:Cellulose; D005982:Glutathione Transferase; D002480:Cellulase; D043366:Cellulose 1,4-beta-Cellobiosidase