A pilot field study was conducted to assess the impact of bioaugmentation with two plasmid pJP4-bearing microorganisms: the natural host, Ralstonia eutropha JMP134, and a laboratory-generated strain amenable to donor counterselection, Escherichia coli D11. The R. eutropha strain contained chromosomal genes necessary for mineralization of 2,4-dichlorophenoxyacetic acid (2,4-D), while the E. coli...

BACKGROUND For many microbial processes, the complexity of the metabolisms and the responses to transient and realistic conditions are difficult to capture in mechanistic models. The cells seem to have an innate intelligence that enables them to respond optimally to environmental changes. Some "intelligent" models have therefore been proposed and compared with a mechanistic model for fed-batch ...

The bacterium Ralstonia eutropha forms cytoplasmic granules of polyhydroxybutyrate that are a source of biodegradable thermoplastic. While much is known about the biochemistry of polyhydroxybutyrate production, the cell biology of granule formation and growth remains unclear. Previous studies have suggested that granules form either in the inner membrane, on a central scaffold, or in the cytopl...

BACKGROUND Lignocellulosic raw materials have extensively been examined for the production of bio-based fuels, chemicals, and polymers using microbial platforms. Since xylose is one of the major components of the hydrolyzed lignocelluloses, it is being considered a promising substrate in lignocelluloses based fermentation process. Ralstonia eutropha, one of the most powerful and natural produce...

Ralstonia eutropha JMP134(pJP4) and several other species of motile bacteria can degrade the herbicide 2,4-dichlorophenoxyacetate (2,4-D), but it was not known if bacteria could sense and swim towards 2,4-D by the process of chemotaxis. Wild-type R. eutropha cells were chemotactically attracted to 2,4-D in swarm plate assays and qualitative capillary assays. The chemotactic response was induced...

A heterologous metabolism of polyhydroxyalkanoate (PHA) biosynthesis and degradation was established in Escherichia coli by introducing the Ralstonia eutropha PHA biosynthesis operon along with the R. eutropha intracellular PHA depolymerase gene. By with this metabolically engineered E. coli, enantiomerically pure (R)-3-hydroxybutyric acid (R3HB) could be efficiently produced from glucose. By e...

Organic acids are considered as potential substrates for biosynthesis of polyhydroxyalkaonates. The acids may also be the metabolic inhibitors at moderate concentration levels. In this study, Ralstonia eutropha was used to elucidate the protein regulations when the bacterial cells pre-cultivated on glucose were exposed to three representative short chain organic acids, acetic, propionic and lev...

To provide 4-hydroxybutyryl-CoA for poly(3-hydroxybutyrate-co-4-hydroxybutyrate) formation from glutamate in Escherichia coli, an acetyl-CoA:4-hydroxybutyrate CoA transferase from Clostridium kluyveri, a 4-hydroxybutyrate dehydrogenase from Ralstonia eutropha, a gamma-aminobutyrate:2-ketoglutarate transaminase from Escherichia coli, and glutamate decarboxylases from Arabidopsis thaliana or E. c...