Molecular characterization of a regulatory protein (PhaR) involved in PHA biosynthesis
نویسندگان
چکیده
Phasins (PhaP) are polyhydroxyalkanoate (PHA) granule-associated proteins that positively affect the PHA synthesis. In the heterologous expression experiment in Escherichia coli, introduction of only phaP caused overproduction of PhaP, and apparent repression of PhaP production was observed in the presence of phaR, which is located in the downstream region of phaP. It indicates that PhaR seems to act as a regulator for the expression of phaP. Gel mobility shift assay using recombinant PhaR protein revealed that PhaR was a DNA binding protein. In vitro expression of phaP was repressed by the addition of the PhaR protein. These results suggest that the PhaR protein negatively regulates phaP expression. We here propose a plausible regulatory mechanism of PhaR that is involved in PHA biosynthesis.
منابع مشابه
The Ralstonia eutropha PhaR protein couples synthesis of the PhaP phasin to the presence of polyhydroxybutyrate in cells and promotes polyhydroxybutyrate production.
Polyhydroxyalkanoates (PHAs) are polyoxoesters that are produced by many bacteria and that accumulate as intracellular granules. Phasins (PhaP) are proteins that accumulate during PHA synthesis, bind PHA granules, and promote further PHA synthesis. Interestingly, PhaP accumulation seems to be strictly dependent on PHA synthesis, which is catalyzed by the PhaC PHA synthase. Here we have tested t...
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