TrCel7A W40A mutagenesis 1 Tryptophan residue at active-site tunnel entrance of Trichoderma reesei cellobiohydrolase Cel7A is important to initiate degradation of crystalline cellulose*
نویسندگان
چکیده
Background: Mutation of W40 residue in a cellobiohydrolase TrCel7A causes a loss of the crystalline cellulose-degrading ability. Results: W40A mutant showed reduced specific activity towards crystalline cellulose and diffused cellulose chain from entrance of active-site tunnel. Conclusions: Trp 40 is essential for chain-end loading to initiate processive hydrolysis of TrCel7A. Significance: The mechanisms of crystalline polysaccharides degradation are clarified.
منابع مشابه
High speed atomic force microscopy visualizes processive movement of Trichoderma reesei cellobiohydrolase I on crystalline cellulose.
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