title: Esterase EstK from Pseudomonas putida mt-2: An enantioselective acetylesterase with activity for deacetylation of xylan and poly(vinylacetate).
abstract: An extracellular esterase gene estK was identified in Pseudomonas putida mt-2 and overexpressed at high levels in Escherichia coli. The recombinant EstK enzyme was purified and characterized kinetically against p-nitrophenyl ester and other aryl-alkyl ester substrates and found to be selective for hydrolysis of acetyl ester substrates with high activity for p-nitrophenyl acetate (kcat5.5 Sec-1, KM285 µM). Recombinant EstK was found to catalyze deacetylation of acetylated beech xylan, indicating a possible in vivo function for this enzyme, and partial deacetylation of a synthetic polymer (poly(vinylacetate)). EstK was found to catalyze enantioselective hydrolysis of racemic 1-phenylethyl acetate, generating 1R-phenylethanol with an enantiomeric excess of 80.4%.
authors.affiliation: Department of Chemistry, University of Warwick, Coventry, UK.
authors.forename: Robert
authors.initials: R
authors.lastname: Millar
authors.affiliation: Department of Chemistry, University of Warwick, Coventry, UK.
authors.forename: Rahman
authors.initials: R
authors.lastname: Rahmanpour
authors.affiliation: Department of Chemistry, University of Warwick, Coventry, UK.
authors.forename: Eugenie Wei Jia
authors.initials: EWJ
authors.lastname: Yuan
authors.affiliation: Department of Chemistry, University of Warwick, Coventry, UK.
authors.forename: Catharine
authors.initials: C
authors.lastname: White
authors.affiliation: Department of Chemistry, University of Warwick, Coventry, UK.
authors.forename: Timothy D H
authors.initials: TDH
authors.lastname: Bugg
mesh_terms: D000107:Acetylation; D055162:Biocatalysis; D004950:Esterases / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*; D006868:Hydrolysis; D007700:Kinetics; D015394:Molecular Structure; D011145:Polyvinyls / Q000737:chemistry / Q000378:metabolism*; D016958:Pseudomonas putida / Q000201:enzymology*; D011994:Recombinant Proteins / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism; D013237:Stereoisomerism; D014990:Xylans / Q000737:chemistry / Q000378:metabolism*
chemical_list: D011145:Polyvinyls; D011994:Recombinant Proteins; D014990:Xylans; D004950:Esterases
keywords: Pseudomonas putida mt-2; esterase; poly(vinylacetate); xylan esterase