Abstract
A phospholipase gene of Photobacterium damselae ssp. piscicida ( ppp ) was cloned from a genomic library and its nucleotide sequence was determined. The open reading frame consisted of 1218 bp encoding a protein of 405 amino acids with a predicted molecular mass of 46 kDa. The PPP had identities (53–55%) with phospholipase and haemolysin of Vibrio spp., while it showed low identities (23–26%) with glycerophospholipid cholesterol acyltransferase of Aeromonas spp. A recombinant PPP (rPPP) with a His tag at the C‐terminus expressed in Escherichia coli and purified showed phospholipase activity. The rPPP also showed lecithin‐dependent haemolytic activity against mammalian erythrocytes and direct haemolytic activity against fish erythrocytes. The culture supernatant of wild‐type P. damselae ssp. piscicida showed phospholipase activity, while that of a PPP gene knockout mutant did not.