PURIFICATION AND PROPERTIES OF A LIPASE FROM PENICILLIUM-EXPANSUM

Penicillium expansum DSM 1994 produces a new, inducible extracellular lipase when grown in medium containing 0.1% olive oil. Maximum activit y was obtained after 4 days of incubation at 20-degrees-C. The enzyme was purified 219-fold by cross-flow filtration, ammonium sulfate preci pitation and hydrophobic interaction chromatography to a final specifi c activity of 558 U/mg. The molecular weight of the homogeneous lipase was (25 kDa) determined by gel filtration and SDS-PAGE, however, it f orms active dimers and higher aggregates as observed after native PAGE . The enzyme was identified as a glycoprotein with a pI of 5.5. The N- terminal sequence shows a homology to sequences of other lipase just b ehind their consensus sequence. Enzyme stability was enhanced by the a ddition of Tween 20 and Lubrol PX. The enzyme showed a maximum activit y at pH 9 at 45-degrees-C and was stable at a broad pH range of 6-10. Lipase of P. expansum showed a preference for triacylglycerols, but no positional specificity.