Purification and characterization of dichloromuconate cycloisomerase from Alcaligenes eutrophus JMP 134

Dichloromuconate cycloisomerase from Alcaligenes eutrophus JMP 134 was purified to homogeneity. The enzyme has an Mr of about 270,000 as determined by gel filtration and consists of six to eight subunits of identical Mr 40,000 as determined by SDS/PAGE. Mn2+ ions as well as thiol groups are required...

Full description

Saved in:
Bibliographic Details
Published inBiochemical journal Vol. 266; no. 3; pp. 877 - 883
Main Authors Kuhm, A E, Schlömann, M, Knackmuss, H J, Pieper, D H
Format Journal Article
LanguageEnglish
Published England 15.03.1990
Subjects
Alcaligenes - enzymology
Alcaligenes eutrophus
Intramolecular Lyases
Isomerases - analysis
Kinetics
Molecular Weight
Substrate Specificity
Online AccessGet full text

Cover

More Information
Summary:Dichloromuconate cycloisomerase from Alcaligenes eutrophus JMP 134 was purified to homogeneity. The enzyme has an Mr of about 270,000 as determined by gel filtration and consists of six to eight subunits of identical Mr 40,000 as determined by SDS/PAGE. Mn2+ ions as well as thiol groups are required for activity. A high Km value of about 4 mM for cis,cis-muconate explains the reported low activity with this compound. Relatively high Km values were also calculated for monochloro-substituted cis,cis-muconates (300-500 microM), in contrast with the low Km value of 20 microM for 2,4-dichloro-cis,cis-muconate. The catalytic constant of the pure enzyme was 3820 min-1 when measured with 2,4-dichloro-cis,cis-muconate.
Bibliography:ObjectType-Article-1
SourceType-Scholarly Journals-1
ObjectType-Feature-2
content type line 23
ISSN:0264-6021
1470-8728