Ralstonia eutropha

A Microbial Biorealm page on the genus Ralstonia eutropha

Classification

Higher order taxa

Domain:Bacteria

Phylum:Proteobacteria

Class: Betaproteobacteria

Order: Burkholderiales

Family:Burkholderiaceae

Genus: Cupriavidus/Ralstonia/Wautersia

Species

Genus Species synonym and strains:

1. Cupriavidus necator

2. Wautersia eutropha

3. Ralstonia eutropha

    a. Ralstonia eutropha JMP 134
    b. Ralstonia eutropha H850
    c. Ralstonia eutropha H16 

NCBI: Taxonomy

NCBI: [1]

Description and significance

Photo courtesy of Dr. Bernardo Gonzalez and Danilo Perez-Pantoja From The Regents of the University of California

Ralstonia eutropha JMP 134 can be found in both soil and water. This bacterium has great potential for use in bioremediation as it is able to degrade an great number of chlorinated aromatic (chloroaromatic) compounds and chemically related pollutants. Ralstonia eutropha H16 was formerly known as Alcaligenes eutrophus which was originally isolated from sludge. Ralstonia eutropha JMP 134 and other strains belonging to this species are models for studying microbial production of “polyhydroxyalkanoates, and chemolithoautotrophic metabolism in aerobic heterotrophs.(JGI)”[1] R. eutropha strains can utilize hydrogen, carbon dioxide and organic compounds for development and is model organism for hydrogen oxidation because it can nurture on hydrogen as the sole energy source. Ralstonia eutropha JMP 134 was isolated dues to its ability to degrade the herbicide 2,4-dichlorophenoxyacetic acid, which was encoded on plasmid as having the function of degrading.

R. eutropha JMP 134 have either rod or coccus shape and has two flagella and two membranes. R. eutropha H16 is Gram negative bacterium and has rod shape. (Gram-negative means it has two membranes and have red or pink stain where as Gram-positive have only one membrane and have blue stain.) Most of the Gram-negative bacteria are pathogenic however in this case, it is not true. They both have motility and are facultative aerobes which can live in both aerobic and anaerobic environments. R. eutropha JMP 134 have multiple habitats and R. eutropha H16 have specialized habitat but both requires non-halophilic (not salty) environment. The optimal temperature is 30 degree Celsius.

Genome structure

R. eutropha JMP 134 has one megaplasmid, two chromosomes and plasmid pJP4. Megaplasmid has 60.6% of G-C (guanine and cytosine) content (a way to characterize genes), 512 proteins and one RNA at the length of 634917 bp (base pair). Chromosome 1 has 64.7% G-C content, 3439 proteins and 66 RNA at the length of 380653 bp. Chromosome 2 has 65.0% of G-C content, 2407 proteins and 20 RNA at the length of 272615 bp. Plasmid pJP4 has 64.7% G-C content, 88 proteins and no RNA found so far at the length of 87688 bp.

R. eutropha H16 has one megaplasmid pHG1 and two chromosomes. Megaplasmid pHG1 had 62.3% G-C content and 429 proteins at the length of 452156 bp, this is where essential genetic information for the “facultatively lithoautrotrophic” and anaerobic existence of its host. Related functional genes form loose clusters into groups in the megaplasmid. Lithoautotrophy-related genes are the largest functional group, which is made up of 41 genes that is responsible for the biosynthesis of four different hydrogenases. There is another cluster that is in charge of denitrification. During sequencing several enzymes involved in the “mineralization of aromatic compounds” were discovered. Chromosome 1 has 66.5% G-C content, 3651 proteins and 60 RNA at the length of 405203 bp. Chromosome 2 has 66.8% G-C content, 2555 proteins and 13 RNA at the length of 290000 bp. [2]

Ecology

Due to its evolutionary ties to eukaryotes, Thermoplasma genus can be used as model organism for researches.

Pathology

There is no known pathogen among different strains of Ralstonia eutropha.

Application to Biotechnology

Does this organism produce any useful compounds or enzymes? What are they and how are they used?

Current Research

Enter summaries of the most recent research here--at least three required

References

1. JGI Microbial Genomics [2]

2. Complete nucleotide sequence of pHG1: a Ralstonia eutropha H16 megaplasmid encoding key enzymes of H(2)-based ithoautotrophy and anaerobiosis. [3]

3. HAMAP: Ralstonia eutropha (strain JMP134) (Alcaligenes eutrophus) complete proteome [4]

Research References

1. Ralstonia eutropha H16 Encodes Two and Possibly Three Intracellular Poly[D-(�)-3-Hydroxybutyrate] Depolymerase Genes [5]

2. Process for the production of polyhydroxyoctanoate by streptomyces lividans [6]

3. Method for the continuous microbiological production of polyhydroxy butyric acid [7]

4. Integrated Recombinant Protein Expression and Purification Platform Based on Ralstonia eutropha [8]

5. The Ralstonia eutropha H16 phasin PhaP1 is targeted to intracellular triacylglycerol inclusions in Rhodococcus opacus PD630 and Mycobacterium smegmatis mc2155, and provides an anchor to target other proteins [9] Edited by student of Rachel Larsen and Kit Pogliano