Premium
Site‐directed mutagenesis of the putative catalytic residues of Trichoderma reesci cellobiohydrolase I and endoglucanase I
Author(s) -
Mitsuishi Yasushi,
Nitisinprasert Sunee,
Saloheimo Markku,
Biese Isa,
Reinikainen Tapani,
Claeyssens Marc,
Keränen Sirkka,
Knowles Jonathan K.C.,
Teeri Tuula T.
Publication year - 1990
Publication title -
febs letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.593
H-Index - 257
eISSN - 1873-3468
pISSN - 0014-5793
DOI - 10.1016/0014-5793(90)81457-y
Subject(s) - site directed mutagenesis , mutagenesis , cellulase , enzyme , chemistry , biochemistry , residue (chemistry) , yeast , active site , trichoderma , biology , mutation , mutant , gene , microbiology and biotechnology
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.