Aspartate Decarboxylation Encoded on the Plasmid in the Soy Sauce Lactic Acid Bacterium, Tetragenococcus halophila D10.

Tetragenococcus halophila D10 decarboxylates aspartate to alanine, but T. halophila D10 derivatives generated by a curing treatment could not (Asd(-) derivatives). We observed by electrophoresis three plasmid bands in T. halophila D10; all Asd(-) derivatives lost the largest of these bands. This plasmid, pD1, has two SalI sites. We cloned and sequenced the 10 kb SalI fragment. The DNA sequence suggests that this fragment contains the aspartate decarboxylating trait.