Physicochemical properties of a lipase from pseudomonas fluorescens

Abstract

The molecular weight of triacylglycerol lipase (EC 3.1.1.3) from Pseudomonas fluorescens is estimated to be approx. 33 000 by sodium dodecyl sulfate electrophoresis and Sephadex G-75 gel filtration. The lipase appears to be a single-chain protein and contains neither sugar nor lipid. The enzyme has a sedimentation coefficient ( s 20, w ) of 3.06, an intrinsic viscosity of 3.0 g/ml and a partial specific volume of 0.730 g/ml, with an isoelectric point of pH 4.46. Amino acid analysis showed that the enzyme contained few sulfur-containing amino acid residues with no disulfide links. The N-terminal residue of the enzyme was found to be alanine and optical rotation dispersion analysis showed that about 20% of the enzyme structure was in a helical configuration.