Molecular and functional characterization of the Rhodopseudomonas palustris no. 7 phosphoenolpyruvate carboxykinase gene.

ABSTRACT: The pckA gene, encoding the gluconeogenic enzyme phosphoenolpyruvate carboxykinase (PEPCK), was cloned by PCR amplification from the purple nonsulfur bacterium Rhodopseudomonas palustris No. 7. Sequencing of a 2.5-kb chromosomal SmaI-PstI fragment containing the structural gene revealed an open reading frame encoding 537 amino acids, homologous to known pckA genes. Primer extension analysis identified a transcriptional start site 72 bp upstream of the pckA initiation codon and an upstream sequence similar to sigma70 promoters. Studies of a pckA-lacZ gene fusion indicated that when cells were grown in minimal media with various carbon sources, such as succinate, malate, pyruvate, lactate, or ethanol, under both anaerobic light and aerobic dark conditions, the pckA gene was induced in log ph

SUBMITTER: Inui M 

PROVIDER: S-EPMC93706 | biostudies-literature | 1999 May

REPOSITORIES: biostudies-literature