ISSN:
1432-072X
Keywords:
Assimilation of 2-haloalkanoic acid
;
2-Chloropropionic acid
;
Pseudomonas sp.
;
Non-stereospecificity
;
New dehalogenase
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Abstract The occurrence of a new bacterial dehalogenase acting on both the optical isomers of 2-halogenated alkanoic acids was demonstrated. When the haloalkanoic acid-utilizing bacteria were screened in a medium containing dl-2-chloropropionate as a sole carbon source, two types of bacteria were isolated: (1) a few strains utilizing both d- and l-isomers of 2-chloropropionate and (2) strains utilizing only the l-isomer. A dehalogenating enzyme was obtained from the cells of Pseudomonas sp. which is able to utilize both isomers. The crude enzyme catalyzed the dehalogenation of d- and l-2-chloropropionates to yield l- and d-isomers of lactate, respectively. The enzyme showed the same pH optimum and heat inactivation rate for the d- and l-isomers. Apparent K m values for d- and l-2-chloropropionates were 4.5 and 1.0 mM, respectively. The enzyme acted specifically on 2-haloalkanoic acids. Activity staining of disc-gels electrophoresed witg the crude enzyme preparation showed that the dehalogenation of d- and l-2-chloropropionates, monochloroacetate, dichloroacetate, 2,2-dichloropropionate, and dl-2-chlorobutyrate is due to a single protein.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00405875
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