Cloning and expression in Escherichia coli of the gene encoding a novel L-2,4-diaminobutyrate decarboxylase of Acinetobacter baumannii.

The gene encoding L-2,4-diaminobutyrate decarboxylase (DABA DC) was cloned from Acinetobacter baumannii ATCC 19606. The gene was evidently under the control of its own promoter. Interestingly, the host carrying this clone also produced an appreciable amount of 1,3-diaminopropane. Restriction mapping and subsequent subcloning of the cloned insert localized the DABA DC gene within a 2.45-kb SphI/EcoRI fragment. For endogenous production of DAP, a 1.75-kb EcoRI/PstI region downstream from the DABA DC gene was further required. Southern blot hybridization revealed some heterogeneity in the DABA DC genes among other Acinetobacter species.