EXTRACELLULAR LIPASE OF PSEUDOMONAS AERUGINOSA

Abstract

Lipase of Pseudomonas aeruginosa was excreted in form of high M,- aggregates consisting of protein and lipopolysaccharide. Solubilization and isoelectric focusing in the presence of the zwitterionic detergent CHAPS yielded in an electrophoretically pure lipase protein of M, 29 kDa with an isoelectric point of 5.9. Charge shift electrophoresis showed that lipase was an amphiphilic protein, its activity was dependent on the presence of detergent. Lipase cleaved a variety of different substrates showing no positional specificity. The lipase gene was cloned and sequenced revealing the lipase consensus sequence Gly-His-Ser-His-Gly. Polyclonal antibodies were raised against purified lipase having a titer of 1400 and a detection limit in the picogram range.