Disease relevance of phaG

• Heterologous expression of phaG in Pseudomonas oleovorans, which is not capable of PHA synthesis from gluconate, enabled PHA synthesis on gluconate as the carbon source [1].
• Production of 3-hydroxydecanoic acid by recombinant Escherichia coli HB101 harboring phaG gene [2].

High impact information on phaG

• Transcriptional induction of phaG was observed when gluconate was provided, and PHA synthesis occurred from this carbon source [1].
• The gene phaG was cloned by phenotypic complementation of these mutants; it encoded a protein of 295 amino acids with a molecular mass of 33,876 Da, and the amino acid sequence exhibited 44% amino acid identity to the primary structure of the rhlA gene product, which is involved in the rhamnolipid biosynthesis in Pseudomonas aeruginosa PG201 [1].
• 3HD production by E. coli HB101 (pLZZGPp) harboring phaG from fructose was 587 mg/l, approximately three times that from cultivation in glucose under same culture conditions [2].
• Effect of heterologous expression of phaG [(R)-3-hydroxyacyl-ACP-CoA transferase] on polyhydroxyalkanoate accumulation from the aromatic hydrocarbon phenylacetic acid in Pseudomonas species [3].
• No transcription of phaG and no PHA accumulation was detected in the rpoN-negative mutant of P. aeruginosa neither from gluconate nor from octanoate as carbon source [4].

Biological context of phaG

• Plasmid pBHR84 complemented the phaG-negative mutant PhaG(N)-21 from P. putida [5].
• Using the PCR strategy, the complete open reading frames of two phaG genes from Pseudomonas stutzeri 1317 and Pseudomonas nitroreducens 0802 were cloned from the genomic DNA and functionally expressed in Pseudomonas putida PHAGN-21 [6].

Associations of phaG with chemical compounds

• When octanoate was used as sole carbon source, only low levels of phaG mRNA were detected in P. putida [5].
• Recombinant P. jessenii C8 harbouring the phaG gene showed a 4.1-fold increase (9.6-39% cell dry weight) in PHA accumulation when grown on phenylacetic acid (15 mM) compared with the wild-type strain [3].
• Southern hybridization experiments with digoxigenin-labeled phaG(Pp) from P. putida and genomic DNA from various pseudomonads indicate that phaG homologues are present in various other pseudomonads [5].

Analytical, diagnostic and therapeutic context of phaG

• We employed PCR to amplify this phaG homologue [5].
• Transcriptional analysis applying reverse transcriptase-polymerase chain reaction showed strong induction of phaG, encoding the transacylase, under nitrogen starvation in P. putida KT2440 and the respective rpoN-negative mutant, indicating an RpoN-independent regulation of phaG [4].

References