title: Dienelactone hydrolase from Pseudomonas cepacia.
abstract: Dienelactone hydrolases have previously been shown to play a crucial role in chlorocatechol degradation via the modified ortho cleavage pathway. Recently, the enzymes induced in 4-fluorobenzoate-utilizing bacteria have been classified into three groups on the basis of their specificity towards cis- and trans-dienelactone. The dienelactone hydrolase and the 3-oxoadipate enol-lactone hydrolase from Pseudomonas cepacia have now been purified to apparent homogeneity and characterized with respect to molecular mass and amino acid composition. The dienelactone hydrolase has a distinct preference for cis-dienelactone and did not convert the trans isomer or muconolactone, 3-oxoadipate enol-lactone, or 4-fluoromuconolactone to a significant extent. In properties like amino acid composition, pH optimum of activity, and lack of inhibition by p-chloromercuribenzoate, the P. cepacia dienelactone hydrolase differed substantially from 3-oxoadipate enol-lactone hydrolases and other dienelactone hydrolases.
authors.affiliation: Institut für Mikrobiologie, Universität Stuttgart, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Schlömann
authors.forename: K L
authors.initials: KL
authors.lastname: Ngai
authors.forename: L N
authors.initials: LN
authors.lastname: Ornston
authors.forename: H J
authors.initials: HJ
authors.lastname: Knackmuss
mesh_terms: D000595:Amino Acid Sequence; D016956:Burkholderia cepacia / Q000201:enzymology*; D002265:Carboxylic Ester Hydrolases / Q000737:chemistry / Q000302:isolation & purification* / Q000378:metabolism; D002384:Catalysis; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008969:Molecular Sequence Data; D008970:Molecular Weight; D013379:Substrate Specificity
chemical_list: D002265:Carboxylic Ester Hydrolases; C021927:3-oxoadipate enol-lactonase; C046130:carboxymethylenebutenolidase