ISSN:
0006-3592
Keywords:
Chemistry
;
Biochemistry and Biotechnology
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Biology
,
Process Engineering, Biotechnology, Nutrition Technology
Notes:
The kinetics of the cellulase-catalyzed conversion of soluble cellulose into glucose have been studied over a range of substrate concentrations and temperatures, and at pH values ranging from 4.75 to 7.0. Lineweaver-Burk plots were linear and led to V = 6.2μM/s and Km = 13.1 mM at pH 5.8 and 25.0°C. The pK values corresponding to the free enzyme are 4.8 and 6.8 and are consistent with carboxyl and imidazole groups as the active ionizing species. These pK values were little changed in the enzyme-substrate intermediate that reacts in the ratedetermining step, suggesting that the ionizing groups are still free in this intermediate. The activation energy corresponding to V/Km is 80.6 kJ/mol, and that corresponding to V is 38.7 kJ/mol. The corresponding entropies of activation are 21 J K-1 mol-1 and -157 J K-1 mol-1, respectively.
Additional Material:
3 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/bit.260251011
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