title: Purification and characterization of a carboxylesterase from Pseudomonas sp. KWI-56.
abstract: An intracellular carboxylesterase from Pseudomonas sp. was overproduced in E. coli, and purified to homogeneity by a combination of hydrogen bond chromatography, gel filtration, and hydrophobic interaction chromatography. Gel filtration and SDS-PAGE suggested that the purified enzyme consisted of two subunits of molecular mass of 28 kDa. Its isoelectric point was 5.9. The enzyme was thermolabile, and showed its maximum activity at 22 degrees C (pH 7.5). Methyl propionate was hydrolyzed at the highest rate among the fatty acid methyl esters tested. PMSF, DFP, PCMB, and HgCl2 inhibited the enzyme markedly, suggesting that serine and/or cysteine is in or near the active site.
authors.affiliation: Osaka Municipal Technical Research Institute, Japan.
authors.forename: A
authors.initials: A
authors.lastname: Sugihara
authors.forename: Y
authors.initials: Y
authors.lastname: Shimada
authors.forename: T
authors.initials: T
authors.lastname: Nagao
authors.forename: T
authors.initials: T
authors.lastname: Iizumi
authors.forename: K
authors.initials: K
authors.lastname: Nakamura
authors.forename: T
authors.initials: T
authors.lastname: Fukase
authors.forename: Y
authors.initials: Y
authors.lastname: Tominaga
mesh_terms: D001483:Base Sequence; D043182:Carboxylesterase; D002265:Carboxylic Ester Hydrolases / Q000737:chemistry / Q000302:isolation & purification* / Q000378:metabolism*; D002850:Chromatography, Gel; D003470:Culture Media; D004591:Electrophoresis, Polyacrylamide Gel; D004795:Enzyme Stability / Q000187:drug effects; D005227:Fatty Acids / Q000378:metabolism; D006860:Hydrogen Bonding; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D007526:Isoelectric Point; D008670:Metals / Q000494:pharmacology; D008969:Molecular Sequence Data; D008970:Molecular Weight; D011549:Pseudomonas / Q000201:enzymology*; D013379:Substrate Specificity; D013696:Temperature; D014280:Triglycerides / Q000378:metabolism
chemical_list: D003470:Culture Media; D005227:Fatty Acids; D008670:Metals; D014280:Triglycerides; D002265:Carboxylic Ester Hydrolases; D043182:Carboxylesterase