title: Extracellular lipase from Pseudomonas aeruginosa is an amphiphilic protein.
abstract: Lipase (triacylglycerol acylhydrolase, EC 3.1.1.3) secreted by Pseudomonas aeruginosa PAC1R was purified from cell-free growth medium by preparative isoelectric focusing. After blotting the N-terminal amino acid sequence and the amino acid composition were determined and compared to P. fragi and P. cepacia lipases yielding significant homology between all three species. Additionally, a consensus sequence K-Y-P-i-v-l-V-H-G was identified residing at the N-terminus of Pseudomonas lipases and in the central part of Staphylococcus lipases. Treatment of lipase with the serine-specific inhibitor diethyl p-nitrophenyl phosphate caused a rapid and complete inhibition of enzyme activity indicating the presence of a serine at the catalytic site as expected from lipase consensus sequences. Upon charge-shift electrophoresis the electrophoretic mobility of purified lipase was shifted either anodally or cathodally in the presence of sodium deoxycholate and cetyltrimethylammoniumbromide, respectively. This result demonstrates that extracellular lipase of P. aeruginosa exhibits an amphiphilic character like intrinsic membrane proteins.
authors.affiliation: Lehrstuhl für Biologie der Mikroorganismen, Ruhr-Universität, Bochum, Germany.
authors.forename: K E
authors.initials: KE
authors.lastname: Jaeger
authors.forename: F J
authors.initials: FJ
authors.lastname: Adrian
authors.forename: H E
authors.initials: HE
authors.lastname: Meyer
authors.forename: R E
authors.initials: RE
authors.lastname: Hancock
authors.forename: U K
authors.initials: UK
authors.lastname: Winkler
mesh_terms: D000595:Amino Acid Sequence; D000596:Amino Acids / Q000032:analysis; D002793:Cholic Acids / Q000494:pharmacology; D003902:Detergents / Q000494:pharmacology; D007525:Isoelectric Focusing; D008049:Lipase / Q000037:antagonists & inhibitors / Q000737:chemistry* / Q000302:isolation & purification; D008969:Molecular Sequence Data; D010755:Organophosphates / Q000494:pharmacology; D011487:Protein Conformation; D011550:Pseudomonas aeruginosa / Q000201:enzymology*; D012689:Sequence Homology, Nucleic Acid
chemical_list: D000596:Amino Acids; D002793:Cholic Acids; D003902:Detergents; D010755:Organophosphates; C034789:diethyl phosphate; D008049:Lipase; C028213:3-((3-cholamidopropyl)dimethylammonium)-1-propanesulfonate