Purification and characterization of thermostable xylose(glucose) isomerase from Bacillus thermoantarcticus

Citation
L. Lama et al., Purification and characterization of thermostable xylose(glucose) isomerase from Bacillus thermoantarcticus, J IND MIC B, 27(4), 2001, pp. 234-240
Citations number
41
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Biotecnology & Applied Microbiology",Microbiology
Journal title
JOURNAL OF INDUSTRIAL MICROBIOLOGY & BIOTECHNOLOGY
ISSN journal
1367-5435 → ACNP
Volume
27
Issue
4
Year of publication
2001
Pages
234 - 240
Database
ISI
SICI code
1367-5435(200110)27:4<234:PACOTX>2.0.ZU;2-N
Abstract
Xylose isomerase produced by Bacillus thermoantarcticus was purified 73-fol d to homogeneity and its biochemical, properties were determined. It was a homotetramer with a native molecular mass of 200 kDa and a: subunit molecul ar mass of 47 kDa, with an isoelectric point at 4.8. The enzyme had a K-m o f 33 mM for xylose and also accepted D-glucose as substrate. Arrhenius plot s of the enzyme activity of xylose isomerase were linear up to a temperatur e of 85 degreesC. Its optimum pH was around 7.0, and it had 80% of its maxi mum activity at pH 6.0. This enzyme required divalent cations for its activ ity and thermal stability. Mn2+, Co2+ or Mg2+ were of comparable efficiency for xylose isomerase reaction, while Mg2+ was necessary for glucose isomer ase reaction.