Cloning, nucleotide sequence and expression in Streptomyces lividans and Escherichia coli of pabB from Lactococcus lactis subsp. lactis NCDO 496

The cloning of the gene pabB encoding the aminase activity of p-aminobenzoate (PABA) synthase in Lactococcus lactis subsp. lactis in pIJ41 was undertaken. These genes are usually expressed in Streptomyces lividans strains, which are inefficient in PABA biosynthesis. The 1.2 kb deletion in the region between the aph promoter and the cloning site in the PIJ41 was associated with the expression of the gene. The localization of the pabB complementing gene in the 1.9 kb segment was induced by the subcloning of the pBR322 and the expression of the cloned L. lactis DNA fragment in Escherichia Coli AB3295.