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Title: Enzymatic properties of immobilized Alcaligenes faecalis cells with cell-associated beta-glucosidase activity

Abstract

Enzymatic properties of Alcaligenes faecalis cells immobilized in polyacrylamide were characterized and compared with those reported for the extracted enzyme, and with those measured for free cells. Many of the properties reflected those of the extracted enzyme rather than those measured in the free whole cells prior to immobilization, suggesting cell disruption during immobilization. These properties included the pH activity profile, a slightly broader pH stability profile, and the activation energy. Electron micrographs showed evidence of cell debris among the polymer matrix. The immobilized cells were not viable, and did not consume glucose. Thermal stability was less after immobilization with a half-line of 16 h at 45 degrees C, and 3.5 h at 50 degrees C. The immobilized preparation was more stable when stored lyophilized rather than in buffer, losing 23 and 52% activity, respectively, after six months. The enzyme was irreversibly inhibited by both acetate and citrate buffers. If the immobilized enzyme is to be used in conjunction with cellulases from Trichoderma reesei for cellulase saccharification, the optimal conditions would be pH 5.5 and 45 degrees C in a buffer containing no carboxylic acid groups.

Authors:
;
Publication Date:
Research Org.:
Univ of Toronto, Toronto, Ontario, Canada Dept of Chemical Engineering and Applied Chemistry
OSTI Identifier:
5872974
Resource Type:
Journal Article
Resource Relation:
Journal Name: Biotechnol. Bioeng.; (United States); Journal Volume: 26:6
Country of Publication:
United States
Language:
English
Subject:
09 BIOMASS FUELS; IMMOBILIZED CELLS; STABILITY; MICROORGANISMS; CELLULASE; CHEMICAL ANALYSIS; CHEMICAL PROPERTIES; ENZYMATIC HYDROLYSIS; ENZYME ACTIVITY; ENZYMES; GLUCOSIDASE; GROWTH; IMMOBILIZED ENZYMES; METABOLISM; CHEMICAL REACTIONS; DECOMPOSITION; GLYCOSYL HYDROLASES; HYDROLASES; HYDROLYSIS; LYSIS; O-GLYCOSYL HYDROLASES; SOLVOLYSIS; 090222* - Alcohol Fuels- Preparation from Wastes or Biomass- (1976-1989); 140504 - Solar Energy Conversion- Biomass Production & Conversion- (-1989)

Citation Formats

Wheatly, M.A., and Phillips, C.R.. Enzymatic properties of immobilized Alcaligenes faecalis cells with cell-associated beta-glucosidase activity. United States: N. p., 1984. Web. doi:10.1002/bit.260260604.
Wheatly, M.A., & Phillips, C.R.. Enzymatic properties of immobilized Alcaligenes faecalis cells with cell-associated beta-glucosidase activity. United States. doi:10.1002/bit.260260604.
Wheatly, M.A., and Phillips, C.R.. 1984. "Enzymatic properties of immobilized Alcaligenes faecalis cells with cell-associated beta-glucosidase activity". United States. doi:10.1002/bit.260260604.
@article{osti_5872974,
title = {Enzymatic properties of immobilized Alcaligenes faecalis cells with cell-associated beta-glucosidase activity},
author = {Wheatly, M.A. and Phillips, C.R.},
abstractNote = {Enzymatic properties of Alcaligenes faecalis cells immobilized in polyacrylamide were characterized and compared with those reported for the extracted enzyme, and with those measured for free cells. Many of the properties reflected those of the extracted enzyme rather than those measured in the free whole cells prior to immobilization, suggesting cell disruption during immobilization. These properties included the pH activity profile, a slightly broader pH stability profile, and the activation energy. Electron micrographs showed evidence of cell debris among the polymer matrix. The immobilized cells were not viable, and did not consume glucose. Thermal stability was less after immobilization with a half-line of 16 h at 45 degrees C, and 3.5 h at 50 degrees C. The immobilized preparation was more stable when stored lyophilized rather than in buffer, losing 23 and 52% activity, respectively, after six months. The enzyme was irreversibly inhibited by both acetate and citrate buffers. If the immobilized enzyme is to be used in conjunction with cellulases from Trichoderma reesei for cellulase saccharification, the optimal conditions would be pH 5.5 and 45 degrees C in a buffer containing no carboxylic acid groups.},
doi = {10.1002/bit.260260604},
journal = {Biotechnol. Bioeng.; (United States)},
number = ,
volume = 26:6,
place = {United States},
year = 1984,
month = 6
}
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