UniProt functional annotation for P62694

UniProt code: P62694.

Organism: Hypocrea jecorina (Trichoderma reesei).
Taxonomy: Eukaryota; Fungi; Dikarya; Ascomycota; Pezizomycotina; Sordariomycetes; Hypocreomycetidae; Hypocreales; Hypocreaceae; Trichoderma.
 
Function: Exocellobiohydrolases (CBH) that catalyzes the hydrolysis of 1,4-beta-D-glucosidic bonds in cellulose to release the disaccharide cellobiose (Ref.4). The degradation of cellulose involves an interplay between different cellulolytic enzymes. Hydrolysis starts with endoglucanases (EGs), which cut internal beta-1,4-glucosidic bonds in cellulose to reduce the polymerization degree of the substrate and create new chain ends for exocellobiohydrolases (CBHs). The CBHs release the disaccharide cellobiose from the non-reducing end of the cellulose polymer chain. Finally, beta-1,4-glucosidases hydrolyze the cellobiose and other short cello-oligosaccharides into glucose units (Probable). {ECO:0000269|Ref.4, ECO:0000305}.
 
Catalytic activity: Reaction=Hydrolysis of (1->4)-beta-D-glucosidic linkages in cellulose and cellotetraose, releasing cellobiose from the non-reducing ends of the chains.; EC=3.2.1.91; Evidence={ECO:0000269|Ref.4};
Subcellular location: Secreted {ECO:0000269|Ref.4}.
Domain: The enzyme consists of two functional domains, a catalytic core joined to a carbohydrate-binding domain (CBM) by a serine-, threonine-, and proline-rich, highly glycosylated linker sequence. {ECO:0000305|PubMed:26307003, ECO:0000305|PubMed:9746354}.
Ptm: N-glycosylated. The catalytic core domain comprises three N-linked glycans which each consist of a single N-acetylglucosamine residue. {ECO:0000269|PubMed:9746354}.
Ptm: O-glycosylated. Within the linker domain, all 8 threonines are variably glycosylated with between at least one, and up to three, mannose residues per site. All serines in this domain are at least partially glycosylated with a single mannose residue (PubMed:9746354). O-glycosylation of the cellulase linker provides protection from proteolysis. Linker glycans also contribute to binding affinity of cellobiohydrolases to cellulose (Probable). {ECO:0000269|PubMed:9746354, ECO:0000305|PubMed:26307003}.
Miscellaneous: T.reesei produces two different exocellobiohydrolases. They are unique in that they can hydrolyze crystalline cellulose in the absence of endoglucanases.
Similarity: Belongs to the glycosyl hydrolase 7 (cellulase C) family. {ECO:0000305}.

Annotations taken from UniProtKB at the EBI.