Cloning and sequencing of the gene encoding α-acetolactate decarboxylase from Leuconostoc oenos

Abstract The alsD gene encoding α-acetolactate decarboxylase was isolated from a genomic library of Leuconostoc oenos, using a screening procedure developed on microtiter plates. The nucleotide sequence of alsD encodes a putative protein of 239 amino acids showing significant similarity with other bacterial α-acetolactate decarboxylases. Upstream from alsD lies an open reading frame (alsS) which is highly similar to bacterial genes coding for catabolic α-acetolactate synthases. Northern (RNA) blotting analyses indicated the presence of a 2.4-kb dicistronic transcript of alsS and alsD. This suggests that the alsS and alsD genes are organized in a single operon.