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Characterization of the highly active polyhydroxyalkanoate synthase of Chromobacterium sp. strain USM2.

ABSTRACT: The synthesis of bacterial polyhydroxyalkanoates (PHA) is very much dependent on the expression and activity of a key enzyme, PHA synthase (PhaC). Many efforts are being pursued to enhance the activity and broaden the substrate specificity of PhaC. Here, we report the identification of a highly active wild-type PhaC belonging to the recently isolated Chromobacterium sp. USM2 (PhaC(Cs)). PhaC(Cs) showed the ability to utilize 3-hydroxybutyrate (3HB), 3-hydroxyvalerate (3HV), and 3-hydroxyhexanoate (3HHx) monomers in PHA biosynthesis. An in vitro assay of recombinant PhaC(Cs) expressed in Escherichia coli showed that its polymerization of 3-hydroxybutyryl-coenzyme A activity was nearly 8-fold higher (2,462 ± 80 U/g) than that of the synthase from the model strain C. necator (307 ± 24 U/g). Specific activity using a Strep2-tagged, purified PhaC(Cs) was 238 ± 98 U/mg, almost 5-fold higher than findings of previous studies using purified PhaC from C. necator. Efficient poly(3-hydroxybutyrate) [P(3HB)] accumulation in Escherichia coli expressing PhaC(Cs) of up to 76 ± 2 weight percent was observed within 24 h of cultivation. To date, this is the highest activity reported for a purified PHA synthase. PhaC(Cs) is a naturally occurring, highly active PHA synthase with superior polymerizing ability.

SUBMITTER: Bhubalan K

PROVIDER: S-EPMC3126384 | biostudies-literature | 2011 May

REPOSITORIES: biostudies-literature

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Characterization of the highly active polyhydroxyalkanoate synthase of Chromobacterium sp. strain USM2.

Bhubalan Kesaven K Chuah Jo-Ann JA Shozui Fumi F Brigham Christopher J CJ Taguchi Seiichi S Sinskey Anthony J AJ Rha Chokyun C Sudesh Kumar K

Applied and environmental microbiology 20110311 9

The synthesis of bacterial polyhydroxyalkanoates (PHA) is very much dependent on the expression and activity of a key enzyme, PHA synthase (PhaC). Many efforts are being pursued to enhance the activity and broaden the substrate specificity of PhaC. Here, we report the identification of a highly active wild-type PhaC belonging to the recently isolated Chromobacterium sp. USM2 (PhaC(Cs)). PhaC(Cs) showed the ability to utilize 3-hydroxybutyrate (3HB), 3-hydroxyvalerate (3HV), and 3-hydroxyhexanoat ...[more]

PMID: 21398494

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Dataset Information

Characterization of the highly active polyhydroxyalkanoate synthase of Chromobacterium sp. strain USM2.

Publications

Characterization of the highly active polyhydroxyalkanoate synthase of Chromobacterium sp. strain USM2.

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