Purification and characterization of the {alpha}-glucuronidase from Thermoanaerobacterium sp. strain JW/SL-YS485, an important enzyme for the utilization of substituted xylans

Journal Article · Wed Mar 01 04:00:00 EST 1995 · Applied and Environmental Microbiology

OSTI ID:96192

Shao, W; Obi, S K.C.; Wiegel, J ^[1]; Puls, J ^[2]

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1. Univ. of Georgia, Athens, GA (United States)
2. Institute fur Holzchemie, Hamburg (Germany)

A cell-associated {alpha}-glucuronidase was purified to gel electrophoretic homogeneity from the thermophilic anaerobic bacterium Thermoanaerobacterium sp. strain JW/SL-YS485. This enzyme had a pI of 4.65, a molecular weight of 130,000, and two subunits; the molecular weight of each subunit was 74,000. The enzyme exhibited the highest level of activity at pH 5.4 and 60{degrees}C, as determined by a 5-min assay. The K{sub m} and k{sub cat} values of the enzyme for 4-methylglucuronosyl xylobiose were 0.76 mM and 1,083 IU/{mu}mol, respectively. The Arrhenius energy was 26.4 kJ/mol. The specific activities of the enzyme with 4-0-methylglucuronosyl xylobiose, 4-0-methylglucuronosyl xylotriose, and 4-0-methylglucuronosyl xylotetraose were 8.4, 4.8, and 3.9 IU/mg, respectively. The purified {alpha}-glucuronidase and a {beta}-xylosidase purified from the same organism interacted synergistically to hydrolyze 4-methylglucuronosyl xylotetraose.

• DOE Contract Number: FG09-89ER14059
• OSTI ID: 96192
• Journal Information: Applied and Environmental Microbiology, Journal Name: Applied and Environmental Microbiology Journal Issue: 3 Vol. 61; ISSN AEMIDF; ISSN 0099-2240
• Country of Publication: United States
• Language: English

Related Subjects

55 BIOLOGY AND MEDICINE
BASIC STUDIES
BACTERIA
BIODEGRADATION
GLUCURONIDASE
PURIFICATION
THERMOPHILIC CONDITIONS
XYLANS