Site‐directed mutagenesis of the putative catalytic residues of Trichoderma reesci cellobiohydrolase I and endoglucanase I

FEBS Letters

Reinikainen, Tapani²  Claeyssens, Marc¹  Nitisinprasert, Sunee²  Keränen, Sirkka²  Saloheimo, Markku²  Teeri, Tuula T.²  Biese, Isa²  Mitsuishi, Yasushi²  Knowles, Jonathan K.C.² 

[1] Laboratorium voor Biochemie, Rijksuniversiteit Gent, K.I. Ledeganekstraat 35, B-9000 Gent, Belgium;VTT Biotechnical Laboratory, PO Box 202, SF-02151 Espoo, Finland

关键词: Site-directed mutagenesis;    Active site;    Cellulase;    Hyperglycosylation;    A;    alanine;    CBH;    cellobiohydrolase;    cbh;    gene coding for CBH;    D;    aspartic acid;    E;    glutamic acid;    EG;    endoglucanase;    egl;    gene coding for EG;    N;    asparagine;    PAGE;    polyacrylamide gel electrophoresis;    Q;    glutamine;    SDS;    sodium dodecyl sulfate;    wt;    wild-type;   

DOI  :  10.1016/0014-5793(90)81457-Y

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Site directed mutagenesis has been performed to test hypotheses concerning the putative active sites of Trichoderma reesci cellobiohydrolase I and endoglucanase I. It is shown that mutagenesis of the residue 1:126, previously proposed to be the proton donor in CBHI, did not totally inactive the enzyme while mutagenesis of the residue 1:127 in the homologous enzyme EG1 resulted in complete loss of activity. These results are compared with those obtained in similar studies of other glucanases and the effects on enzymatic activity of hyperglycosylation of the yeast produced cellulases are discussed.

【 授权许可】

Unknown