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Poly(3-hydroxybutyrate) synthesis genes in Azotobacter sp. strain FA8.

ABSTRACT: Genes responsible for the synthesis of poly(3-hydroxybutyrate) (PHB) in Azotobacter sp. FA8 were cloned and analyzed. A PHB polymerase gene (phbC) was found downstream from genes coding for beta-ketothiolase (phbA) and acetoacetyl-coenzyme A reductase (phbB). A PHB synthase mutant was obtained by gene inactivation and used for genetic studies. The phbC gene from this strain was introduced into Ralstonia eutropha PHB-4 (phbC-negative mutant), and the recombinant accumulated PHB when either glucose or octanoate was used as a source of carbon, indicating that this PHB synthase cannot incorporate medium-chain-length hydroxyalkanoates into PHB.

SUBMITTER: Pettinari MJ

PROVIDER: S-EPMC93310 | biostudies-literature | 2001 Nov

REPOSITORIES: biostudies-literature

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Poly(3-hydroxybutyrate) synthesis genes in Azotobacter sp. strain FA8.

Pettinari M J MJ Vázquez G J GJ Silberschmidt D D Rehm B B Steinbüchel A A Méndez B S BS

Applied and environmental microbiology 20011101 11

Genes responsible for the synthesis of poly(3-hydroxybutyrate) (PHB) in Azotobacter sp. FA8 were cloned and analyzed. A PHB polymerase gene (phbC) was found downstream from genes coding for beta-ketothiolase (phbA) and acetoacetyl-coenzyme A reductase (phbB). A PHB synthase mutant was obtained by gene inactivation and used for genetic studies. The phbC gene from this strain was introduced into Ralstonia eutropha PHB-4 (phbC-negative mutant), and the recombinant accumulated PHB when either glucos ...[more]

PMID: 11679365

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