title: An extracellular carboxylesterase from the basidiomycete Pleurotus sapidus hydrolyses xanthophyll esters.
abstract: An extracellular enzyme capable of efficient hydrolysis of xanthophyll esters was purified from culture supernatants of the basidiomycete Pleurotus sapidus. Under native conditions, the enzyme exhibited a molecular mass of 430 kDa, and SDS-PAGE data suggested a composition of eight identical subunits. Biochemical characterisation of the purified protein showed an isoelectric point of 4.5, and ideal hydrolysis conditions were observed at pH 5.8 and 40 degrees C. Partial amino acid sequences were derived from N-terminal Edman degradation and from mass spectrometric ab initio sequencing of internal peptides. An 1861-bp cDNA containing an open reading frame of 1641 bp was cloned from a cDNA library that showed ca. 40% homology to Candida rugosa lipases. The P. sapidus carboxylesterase represents the first enzyme of the lipase/esterase family from a basidiomycetous fungus that has been characterised at the molecular level.
authors.affiliation: Zentrum Angewandte Chemie, Institut für Lebensmittelchemie der Universität Hannover, Wunstorfer Strasse 14, D-30453 Hannover, Germany. zorn@lci.uni-hannover.de
authors.forename: Holger
authors.initials: H
authors.lastname: Zorn
authors.forename: Henning
authors.initials: H
authors.lastname: Bouws
authors.forename: Meike
authors.initials: M
authors.lastname: Takenberg
authors.forename: Manfred
authors.initials: M
authors.lastname: Nimtz
authors.forename: Rita
authors.initials: R
authors.lastname: Getzlaff
authors.forename: Dietmar E
authors.initials: DE
authors.lastname: Breithaupt
authors.forename: Ralf G
authors.initials: RG
authors.lastname: Berger
mesh_terms: D000595:Amino Acid Sequence; D002265:Carboxylic Ester Hydrolases / Q000737:chemistry / Q000302:isolation & purification*; D004952:Esters / Q000737:chemistry; D045604:Extracellular Fluid / Q000201:enzymology; D006868:Hydrolysis; D007526:Isoelectric Point; D008049:Lipase / Q000737:chemistry / Q000302:isolation & purification; D008958:Models, Molecular; D008969:Molecular Sequence Data; D020076:Pleurotus / Q000201:enzymology*; D011487:Protein Conformation; D024341:Xanthophylls / Q000737:chemistry*
chemical_list: D004952:Esters; D024341:Xanthophylls; D002265:Carboxylic Ester Hydrolases; D008049:Lipase