Purification and Biochemical Characterization of a Novel Alkaline (Phospho)lipase from a Newly Isolated Fusarium solani Strain

Abstract

An extracellular lipase from Fusarium solani strain (F. solani lipase (FSL)) was purified to homogeneity by ammonium sulphate precipitation, gel filtration and anion exchange chromatography. The purified enzyme has a molecular mass of 30kDa as estimated by sodium dodecyl sulphate polyacrylamide gel electrophoresis. The 12 NH(2)-terminal amino acid residues showed a high degree of homology with a putative lipase from the fungus Necteria heamatoccocae. It is a serine enzyme, like all known lipases from different origins. Interestingly, FSL has not only lipase activity but also a high phospholipase activity which requires the presence of Ca(2+) and bile salts. The specific activities of FSL were about 1,610 and 2,414U/mg on olive oil emulsion and egg-yolk phosphatidylcholine as substrates, respectively, at pH8.0 and 37°C. The (phospho)lipase enzyme was stable in the pH range of 5-10 and at temperatures below 45°C.