Polaromonas naphthalenivorans: Difference between revisions
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==Cell structure and metabolism== | ==Cell structure and metabolism== | ||
Unlike other species from the genus <i>Polaromonas</i>, <i>P. naphthalenivorans</i> does not have flagella. (2) | |||
<i>P. naphthalenivorans</i> grows optimally at a temperature of 20oC (can grow between 4oC and 35oC) and pH of 7.0-7.5 (can grow between pH 6.0 and pH 9.0). It can be found as individual organisms that are 1-4um in diameter or in small clusters of loosely adherent cells. Colonies appear circular and convex, with a smooth surface and no pigment production. (2) | |||
<i>P. naphthalenivorans</i> has the unusual ability to store all three common types of prokaryotic cellular reserve materials (PHA, polyglucose and polyphosphate granules) during its exponential growth phase. (2) | |||
<i>P. naphthalenivorans</i> is an aerobic heterotroph that is capable of utilizing glucose and other simple sugars, and can grow with naphthalene as its sole carbon source. (2) Naphthalene degradation occurs through two pathways, both of which are chromosomally encoded. These two pathways are the naphthalene degradation upper pathway and naphthalene degradation lower pathway. The upper pathway converts naphthalene to salicylate and the lower pathway converts salicylate to pyruvate and acetyl coenzyme A via meta cleavage. (6) | |||
==Ecology== | ==Ecology== | ||
Revision as of 17:32, 29 August 2007
A Microbial Biorealm page on the genus Polaromonas naphthalenivorans
Classification
Higher order taxa
Bacteria; Protobacteria; Betaprotobacteria; Burkholderiales; Comamonadaceae, Polaromonas
Species
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NCBI: Taxonomy |
Polaramonas napthalenivorans CJ2
Description and significance
P. naphthalenivorans is an aquatic gram-negative, non-spore forming, non-motile coccus that is capable of growth with naphthalene as its sole carbon and energy source. (2)
The genus Polaromonas was proposed in 1996 and contained only one species, P. vacuolata, until 2004 when P. naphthalenivorans was discovered. (3) Strain CJ2 was isolated from coal-tar-contaminated freshwater sediment in South Glens Falls, New York, USA. (1) It was discovered using stable isotope probing (SIP), a technique that enabled researchers to follow the flow of labeled carbon atoms from naphthalene to the DNA of naturally occurring microbial populations in the environment such as P. naphthalenivorans. (4)
It is important to have the genome of P. naphthalenivorans sequenced because of its ability to efficiently remove naphthalene from solution. Naphthalene is a polycyclic aromatic hydrocarbon (PAH) that can cause contamination of soil, water or sediment and can be toxic and/or carcinogenic. (2)
Genome structure
The complete genome of P. naphthalenivorans is 4,410,291 base pairs long, with a G+C content of 61.5%. (2,5) It consists of a circular chromosome that is 4.4Mbp long and encodes 4084 proteins and eight circular plasmids that collectively encode 2195 proteins. pPNAP01 is .35Mbp long and encodes 205 proteins. pPNAP02 is .19Mbp long and encodes 161 proteins. pPNAP03 is .17Mbp long and encodes 155 proteins. pPNAP04 is .14Mbp long and encodes 136 proteins. pPNAP05 is .059Mbp long and encodes 52 proteins. pPNAP06 is .022Mbp long and encodes 20 proteins. pPNAP07 is .0099Mbp long and encodes 11 proteins. pPNAP08 is .0065Mbp long and encodes 5 proteins. (6)
Comparative 16S rDNA analysis showed that P. naphthalenivorans is related to the family Comamonadaceae, with its nearest phylogenetic relative being P. vacuolata (97.1% similar). (2)
The naphthalene catabolic genes of P. naphthalenivorans are separated into a large cluster (25,748bp) and small cluster (14,217bp) and many of these genes are homologous to the catabolic genes of Ralstonia U2, an organism that uses the gentisate pathway to convert naphthalene to central metabolites. Three open reading frames present in Ralstonia U2 (nagY, nagM and nagN) are missing in P. naphthalenivorans. (6)
Cell structure and metabolism
Unlike other species from the genus Polaromonas, P. naphthalenivorans does not have flagella. (2)
P. naphthalenivorans grows optimally at a temperature of 20oC (can grow between 4oC and 35oC) and pH of 7.0-7.5 (can grow between pH 6.0 and pH 9.0). It can be found as individual organisms that are 1-4um in diameter or in small clusters of loosely adherent cells. Colonies appear circular and convex, with a smooth surface and no pigment production. (2)
P. naphthalenivorans has the unusual ability to store all three common types of prokaryotic cellular reserve materials (PHA, polyglucose and polyphosphate granules) during its exponential growth phase. (2)
P. naphthalenivorans is an aerobic heterotroph that is capable of utilizing glucose and other simple sugars, and can grow with naphthalene as its sole carbon source. (2) Naphthalene degradation occurs through two pathways, both of which are chromosomally encoded. These two pathways are the naphthalene degradation upper pathway and naphthalene degradation lower pathway. The upper pathway converts naphthalene to salicylate and the lower pathway converts salicylate to pyruvate and acetyl coenzyme A via meta cleavage. (6)
Ecology
Describe any interactions with other organisms (included eukaryotes), contributions to the environment, effect on environment, etc.
Pathology
There are no known diseases caused by P. naphthalenivorans CJ2.
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
Edited by Christina Hopson, student of Rachel Larsen
