''Ruegeria pomeroyi'' is a species of

Gram-negative Gram-negative bacteria are bacteria that, unlike gram-positive bacteria, do not retain the crystal violet stain used in the Gram staining method of bacterial differentiation. Their defining characteristic is that their cell envelope consists ...

, rod-shaped, aerobic

dimethylsulfoniopropionate Dimethylsulfoniopropionate (DMSP), is an organosulfur compound with the formula (CH3)2S+CH2CH2COO−. This zwitterionic metabolite can be found in marine phytoplankton, seaweeds, and some species of terrestrial and aquatic vascular plants. ...

- demethylating bacterium. Its type strain is DSS-3^T (=ATCC 700808^T =DSM 15171^T). Its genome has been sequenced.

Discovery

''Ruegeria pomeroyi'' was discovered off the coast of the Eastern United States in the laboratory of Mary Ann Moran, Ph.D. at the University of Georgia. ''R. pomeroyi'' was named after Lawrence "Larry" Pomeroy, the marine microbial ecologist who notably established in 1974 that

marine bacteria Marine prokaryotes are marine bacteria and marine archaea. They are defined by their habitat as prokaryotes that live in marine environments, that is, in the saltwater of seas or oceans or the brackish water of coastal estuaries. All cellu ...

play a substantial and pivotal role in

ocean food web A marine food web is a food web of marine life. At the base of the ocean food web are single-celled algae and other plant-like organisms known as phytoplankton. The second trophic level ( primary consumers) is occupied by zooplankton which feed o ...

dynamics. Pomeroy was also a researcher at the University of Georgia.

Genome

The genome of the ''Ruegeria pomeroyi'' type strain (DSS-3) was completed in 2004. The genome is 4,109,442 base pairs long with a megaplasmid that is 491,611 base pairs long.

Ecology

''Ruegeria pomeroyi'' is a coastal ocean bacterium in a lineage of bacteria commonly considered ecological "generalists." The relatively large genome of ''R. pomeroyi,'' as compared to other marine bacterial species, supports this concept. In line with this, ''R. pomeroyi'' has a highly versatile ability to utilize and

sequester carbon Carbon sequestration is the process of storing carbon in a carbon pool. It plays a crucial role in limiting climate change by reducing the amount of carbon dioxide in the atmosphere. There are two main types of carbon sequestration: biologic ( ...

and energy. ''R. pomeroyi'' also has the ability to degrade

(DMSP), a sulfur-containing algal osmolyte and use the sulfur to synthesize sulfur-containing amino acids. Although many marine bacteria are capable of degrading DMSP, the genes and proteins used to do so were elusive to researchers for many years. It was in ''R. pomeroyi'' that Howard and colleagues discovered the first gene that degrades DMSP. This gene (''dmdA'') codes for a protein (DmdA) that removes a methyl group (-CH3) from DMSP. The DmdA protein has since been further characterized from ''R. pomeroyi'', as well as the transcriptional response of the ''dmdA'' gene to the presence of DMSP and the sequence diversity of the ''dmdA'' gene. This demethylation process is the first step in the highly sought-after demethylation pathway of DMSP degradation in marine bacteria. Following the discovery of the ''dmdA'' gene, the gene sequence was used to establish that over half of marine bacteria, including both open-ocean and coastal bacteria, are capable of demethylating DMSP. Following the discovery of the demethylation pathway of DMSP degradation in ''R. pomeroyi'', an alternative pathway of DMSP degradation was discovered in which DMSP is cleaved in half instead of demethylated, a process which ''R. pomeroyi'' also is capable.

Discovery

Genome

Ecology

References

Further reading