title: Purification and characterization of an extracellular lipase from Penicillium candidum.
abstract: Penicillium candidum produces and secretes a single extracellular lipase with a monomer molecular weight of 29 kDa. However, this enzyme forms dimers and higher molecular weight aggregates under nondenaturing conditions. The lipase from P. candidum was purified 37-fold using Octyl-Sepharose CL-4B and DEAE-Sephadex columns. The optimal assay conditions for lipase activity were 35 degrees C and pH 9. The lipase was stable in the pH range of 5-6 with a pl of 5.5, but rapid loss of the enzyme activity was observed above 25 degrees C. Tributyrin was found to be the best substrate for the P. candidum lipase, among those tested. Metal ions such as Fe2+ and Cu2+ inhibited enzymatic activity and only Ca2+ was able to slightly enhance lipase activity. Ionic detergents inhibited the activity of the enzyme, whereas nonionic detergents stimulated lipase activity.
authors.affiliation: Departamento de Biotecnología, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Apartado Postal 70228, México D.F. 04510, México.
authors.forename: B
authors.initials: B
authors.lastname: Ruiz
authors.forename: A
authors.initials: A
authors.lastname: Farrés
authors.forename: E
authors.initials: E
authors.lastname: Langley
authors.forename: F
authors.initials: F
authors.lastname: Masso
authors.forename: S
authors.initials: S
authors.lastname: Sánchez
mesh_terms: D000595:Amino Acid Sequence; D002118:Calcium / Q000494:pharmacology; D003300:Copper / Q000494:pharmacology; D003902:Detergents / Q000494:pharmacology; D019281:Dimerization; D004591:Electrophoresis, Polyacrylamide Gel; D004655:Emulsions; D004791:Enzyme Inhibitors / Q000494:pharmacology; D004795:Enzyme Stability; D005296:Ferrous Compounds / Q000494:pharmacology; D006863:Hydrogen-Ion Concentration; D008049:Lipase / Q000737:chemistry / Q000302:isolation & purification* / Q000378:metabolism; D008969:Molecular Sequence Data; D008970:Molecular Weight; D010407:Penicillium / Q000201:enzymology*; D017385:Sequence Homology; D013053:Spectrophotometry; D013379:Substrate Specificity; D013696:Temperature; D014280:Triglycerides / Q000378:metabolism
chemical_list: D003902:Detergents; D004655:Emulsions; D004791:Enzyme Inhibitors; D005296:Ferrous Compounds; D014280:Triglycerides; D003300:Copper; D008049:Lipase; C005830:tributyrin; D002118:Calcium