title: Enzymatic dehalogenation of 4-chlorobenzoate by extracts from Arthrobacter sp. SU DSM 20407.
abstract: In extracts from Arthrobacter sp. SU DSM 20407 an enzyme was detectable, that converted 4-chlorobenzoate into 4-hydroxybenzoate. This conversion was also observed when no oxygen was present in the reaction mixture. Boiling for 5 min destroyed the enzyme activity. 4-Bromo- and 4-iodobenzoate were substrates for the enzyme too, but not 4-fluorobenzoate, 4-chlorophenylacetate and 4-chlorocinnamic acid. The enzyme showed optimum activity at 16 degrees C and at pH 7-7.5. The specific activity in the extracts varied between 0.5 and 5 mU/mg of protein. Zn2+ and Cu2+ inhibited the enzyme, while H2O2 slightly activated. In contrast to all other 4-chlorobenzoate dehalogenases described before the enzyme was not inhibited by EDTA, nor was it activated by Mn2+. Other divalent ions also had no effect. The molecular mass of the enzyme was 45,000 +/- 5,000 Da as judged by gel-filtration.
authors.affiliation: Institut für Mikrobiologie, Universität Hohenheim.
authors.forename: R
authors.initials: R
authors.lastname: Müller
authors.forename: R H
authors.initials: RH
authors.lastname: Oltmanns
authors.forename: F
authors.initials: F
authors.lastname: Lingens
mesh_terms: D001173:Arthrobacter / Q000201:enzymology*; D002723:Chlorobenzoates / Q000378:metabolism*; D006867:Hydrolases / Q000302:isolation & purification / Q000378:metabolism*; D062385:Hydroxybenzoates / Q000378:metabolism; D007700:Kinetics; D008970:Molecular Weight; D010226:Parabens; D013379:Substrate Specificity
chemical_list: D002723:Chlorobenzoates; D062385:Hydroxybenzoates; D010226:Parabens; D006867:Hydrolases; C042846:4-chlorobenzoate dehalogenase; C040768:4-chlorobenzoic acid; C038193:4-hydroxybenzoic acid