Enzyme-catalysed non-oxidative decarboxylation of aromatic acids: I. Purification and spectroscopic properties of 2,3 dihydroxybenzoic acid decarboxylase from Aspergillus niger
Kamath, A.V.; Dasgupta, D.; Vaidyanathan, C.S.
Biochemical and Biophysical Research Communications 145(1): 586-595
1987
ISSN/ISBN: 0006-291X PMID: 3593354 Document Number: 291064
In order to understand the molecular mechanism of non-oxidative decarboxylation of aromatic acids observed in microbial systems, 2,3 dihydroxybenzoic acid (DHBA) decarboxylase from Aspergillus niger were purified to homogeneity by affinity chromatography. The enzyme (Mr 120 kDa) had four identical subunits (28 kDa each) and was specific for DHBA. It had a pH optimum of 5.2 and Km was 0.34 mM. The decarboxylation did not require any cofactors, nor did the enzyme have any pyruvoyl group at the active site. The carboxyl group and hydroxyl group in the ortho-position were required for activity. The preliminary spectroscopic properties of the enzyme are also reported.