کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1952617 | 1057218 | 2009 | 7 صفحه PDF | دانلود رایگان |
![عکس صفحه اول مقاله: Transglycosylating and hydrolytic activities of the β-mannosidase from Trichoderma reesei Transglycosylating and hydrolytic activities of the β-mannosidase from Trichoderma reesei](/preview/png/1952617.png)
A purified β-mannosidase (EC 3.2.1.25) from the fungus Trichoderma reesei has been identified as a member of glycoside hydrolase family 2 through mass spectrometry analysis of tryptic peptides. In addition to hydrolysis, the enzyme catalyzes substrate transglycosylation with p-nitrophenyl β-mannopyranoside. Structures of the major and minor products of this reaction were identified by NMR analysis as p-nitrophenyl mannobiosides and p-nitrophenyl mannotriosides containing β-(1 → 4) and β-(1 → 3) linkages. The rate of donor substrate hydrolysis increased in presence of acetonitrile and dimethylformamide, while transglycosylation was weakly suppressed by these organic solvents. Differential ultraviolet spectra of the protein indicate that a rearrangement of the hydrophobic environment of the active site following the addition of the organic solvents may be responsible for this hydrolytic activation.
Journal: Biochimie - Volume 91, Issue 5, May 2009, Pages 632–638