VARIANTS OF CELLOBIOHYDROLASES

摘要

Disclosed are a number of homologs and variants of Hypocrea jecorina Ce17A (formerly Trichoderma reesei cellobiohydrolase I or CBH1), nucleic acids encoding the same and methods for producing the same. The homologs and variant cellulases have the amino acid sequence of a glycosyl hydrolase of family 7A wherein one or more amino acid residues are substituted and/or deleted.

主权项

1. An isolated variant of a parent cellobiohydrolase (CBH) enzyme, wherein said variant has cellulase activity, comprises at least one amino acid substitution, has at least 80% sequence identity to SEQ ID NO:3, and has at least one improved property over said parent CBH enzyme selected from: (a) expression (Protein Content Determination), (b) PASC Hydrolysis Assay, (c) PASC Hydrolysis Assay in the Presence of EG2, (d) PASC Hydrolysis Assay After Heat Incubation, (e) Whole Hydrolysate PCS (whPCS) Assay, (f) Dilute Ammonia Corn Cob (daCC) Assay, and (g) dilute ammonia corn stover (daCS) assay; and wherein the at least one amino acid substitution is at a position selected from the group consisting of: A414, G22, R394, T417, P227, T255, V403, F280, E337, P258, T332, T296, N49, Y493, S196, G430, T246, Y247, N307, T356, Y466, S357, Q27, S387, L318, T389, Y303, Y370, K287, T285, N350, D249, F338, S113, Y492, S398, T226, Y371, A316, K346, G340, S342, D368, M374, D179, E236, Y474, G391, F418, F311, R251, T281, V104, L326, A224, and E385, wherein the position of each amino acid substitution corresponds to SEQ ID NO:3.