Characterization of Recombinant UDP-galactopyranose Mutase from Aspergillus Fumigatus

Abstract

UDP-galactopyranose mutase (UGM) is a flavin-containing enzyme that catalyzes the conversion of UDP-galactopyranose to UDP-galactofuranose, the precursor of galactofuranose, which is an important cell wall component in Aspergillus fumigatus and other pathogenic microbes. A. fumigatus UGM (AfUGM) was expressed in Escherichia coli and purified to homogeneity. The enzyme was shown to function as a homotetramer by size-exclusion chromatography and to contain ∼50% of the flavin in the active reduced form. A kcat value of 72±4s-1 and a KM value of 110±15μM were determined with UDP-galactofuranose as substrate. In the oxidized state, AfUGM does not bind UDP-galactopyranose, while UDP and UDP-glucose bind with Kd values of 33±9μM and 90±30μM, respectively. Functional and structural differences between the bacterial and eukaryotic UGMs are discussed. © 2010.

Department(s)

Chemistry

Comments

National Institute of General Medical Sciences, Grant R01GM094469

Keywords and Phrases

Aspergillosis; Flavoenzyme; Galactofuranose; Non-redox reaction; UDP-galactopyranose mutase

International Standard Serial Number (ISSN)

1096-0384; 0003-9861

Document Type

Article - Journal

Document Version

Citation

File Type

text

Language(s)

English

Rights

© 2024 Elsevier, All rights reserved.

Publication Date

01 Oct 2010

PubMed ID

20615386

Link to Full Text

Share

 
COinS