title: Purification and characterisation of acetolactate decarboxylase from Leuconostoc lactis NCW1.
abstract: A two-step strategy involving DEAE-cellulose and POROS PI anion exchange chromatography has been developed for rapid purification of acetolactate decarboxylase (ALD) from Leuconostoc lactis NCW1. This results in 5333-fold purification with a yield of 30%. Purified ALD is a dimer of 49-kDa subunits, has a pH optimum of 6.0, a pI of 4.2 and its activity is independent of metals or branched chain amino acids. At the optimum pH, the K(m) for 2-acetolactate (ALA) was found to be 1.3 mM and the turnover number was 4000 min(-1). N-terminal sequence comparison with other ALDs showed little sequence conservation in this region. Purified ALD does not catalyse direct production of diacetyl from ALA, unlike the crude extract.
authors.affiliation: Department of Biochemistry, University College Cork, Ireland.
authors.forename: S M
authors.initials: SM
authors.lastname: O'Sullivan
authors.forename: S
authors.initials: S
authors.lastname: Condon
authors.forename: T M
authors.initials: TM
authors.lastname: Cogan
authors.forename: D
authors.initials: D
authors.lastname: Sheehan
mesh_terms: D000837:Anion Exchange Resins; D002262:Carboxy-Lyases / Q000737:chemistry / Q000302:isolation & purification* / Q000378:metabolism; D003931:Diacetyl / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D007526:Isoelectric Point; D007934:Leuconostoc / Q000201:enzymology* / Q000378:metabolism; D008970:Molecular Weight
chemical_list: D000837:Anion Exchange Resins; D002262:Carboxy-Lyases; C023746:acetolactate decarboxylase; D003931:Diacetyl