Thermotoga naphthophila

From Wikipedia, the free encyclopedia
Jump to navigation Jump to search

Thermotoga naphthophila
Scientific classification
T. naphthophila
Binomial name
Thermotoga naphthophila
Takahata et al. 2001

Thermotoga naphthophila is a hyperthermophilic, anaerobic, non-spore-forming, rod-shaped fermentative heterotroph, with type strain RKU-10T.[1]


Taxonomical Meaning[edit]

The taxonomic information for Thermotoga naphthophila is the following: Domain, Bacteria[2]; Phylum, Thermotogae[3] ; Order, Thermotogales[3] ; Family, Thermotogaceae[4] ; Genus, Thermotoga[4]; Species, T. naphthophila[3] . Thermotoga naphthophila is an anaerobic, sulfur-compound fixing, hyperthermophile.[2][3] The species name is originally Greek. The term "naphtha" means a light petroleum substance that dilutes minerals to bitumen and "-philos" means love. This translation of the species name combines to form "bitumen-loving".[3][5]


Thermotoga naphthophila can be found under strain types RKU-10, DSM-13996, and JCM-10882T. T. naphthophila cell size ranges within 2-7 micrometers (m) long by 0.7- 1.0 m wide.[3] Based on 16S rDNA sequences,Thermotoga petrophila, strain RKU-1, is the closest relative to T.naphthophila.[3] Other close relatives of T. naphthophila include Thermotoga maritima and Thermotoga neapolitan according to 16S rDNA analysis.[3] T. maritima has an average 5m length.[6] Strains isolated from oil reservoirs, but not considered apart of the T. naphthophila clade include the following species: T. subterranean, T. hypogea, and T. elfii.[3]

Discovery of Organism[edit]

T. naphthophila was originally discovered by Takahata in the subterranean Kubiki oil reservoir of Niigata, Japan.[2][3][5] This organism was found with another bacterium called Thermotoga petrophila, RKU-1[3]. In order to transport the species samples, they were placed into sterile glass bottles in cooler boxes with ice.[3] After arriving to the lab, the species were isolated on a medium of 0.2% yeast extract (YE) in artificial seawater at a pH of 7.[3] Hydrochloric acid (HCl) was added to the sample at room temperature after taking out the yeast extract. Containers of liquid medium were placed into 30 milliliter (mL) tubes and subsequentially exposed to H2 reduced copper furnace heat with oxygen free nitrogen.[3] Then, sodium sulfide brought the pH of the medium to a range of 6.9-7.1 and the species were purified with Gelrite plating, an agar substitute.[3] Thermotoga naphthophila naturally has a growth pH range of 5.4-9.0, but optimally prefers a pH of 7.0.[3]

Exposure Methods[edit]

T. naphthophila tolerance ranges for pH and sodium chloride (NaCl) concentrations were found using inoculated YE-mediums incubated at 80°C to view the species growth.[3] Takahata exposed the bacteria to various buffers in order to get a better understanding of pH effects. Various gas phases were used to expose the species growth in 10 mL mediums.[3] Additionally, the growth of the species was exposed to 1% cellulose, kerosene, light oil, chitin, crude oil and A-heavy oil in duplicates of 30 mL mediums.[3] Takahata utilized a high performance liquid chromatography (HPLC) and guanine and cytosine (GC) concentrations to collect metabolic product data from the species. Electron acceptors such as sulfate, thiosulfate, and elemental sulfur were investigated on YE-based mediums.[3] A polymerase chain reaction (PCR) technique was used to amplify the DNA base sequence and collect the gyrase B (gyrB) subunit gene from true micro-organisms identified above.[3]

Preliminary Characteristics[edit]

Optimum Growth[edit]

T. naphthophila and T. petrophila can grow at temperatures ranging between 47-88°C on yeast extract, peptone, glucose, fructose, ribose, arabinose, sucrose, lactose maltose and starch as sole carbon sources.[3] While in the presence of thiosulfate, T. petrophila is inhibited and T. naphthophila continues growing. Elemental sulfur can be reduced to hydrogen sulfide through both T. petrophila and T. naphthophila.[3] According to the Takahata et. al. (2000), these two species are more phylogenetically related than any other Thermotoga species due to sugar use, elemental sulfur effects, and thiosulfate.


Thermotoga naphthophila is a rod-shaped species.[3] It has 2-7m in length by 0.8-1.2 m in width and multiple flagella.[3][5] It also possesses a unique morphology trait exclusive to the Thermotoga genus, an outer sheath-like structure dubbed a “toga”.[3] T. naphthophila is a hyperthermophile with an optimal temperature of 80°C (176°F), but can survive in 48-86°C (118.4-186.8°F).[3][5][7] According to a 16S rDNA sequence analysis, its 1,809,823 GC content was 46.1 mol% which increases thermostability of the DNA.[3][4][5]


T. naphthophila requires yeast extract, peptone, glucose, galactose, fructose, mannitol, ribose, arabinose, sucrose, lactose, maltose or starch as the sole carbon and energy source for nutrient requirements.[3] Thermotoga naphthophila was unable to survive on proteins, amino acids, organic acids, alcohols, chitin, or hydrocarbons as a sole carbon and energy source.[3] According to the Takahata, lactate, acetate, carbon dioxide, and hydrogen gas are its end products from glucose fermentation. Thermotoga naphthophila is unique, when compared to T. petrophila, in that it reduces elemental sulfur to hydrogen sulfide, but in the presence of elemental sulfur, its growth rate and cellular yield decrease.[3] T. naphthophila also reduces thiosulfate to hydrogen sulfide at a lower rate.[3] According to the previously mentioned article, the microbe’s growth rate and cellular yield is not affected in the presence of thiosulfate.


No known studies have identified Thermotoga naphthophila as pathogenic.[3] Takahata et. al. observed the organism’s sensitivity to various antibiotics on agar plates for 7 days at 70 °C. T. naphthophila is sensitive to 100 µg rifampicin, streptomycin, vancomycin or chloramphenicol per milliliter.[3] Thermotoga naphthophila is a unique species of the Thermotoga genus in that it is one of the two known Thermotogales to have an operon in its genome that encodes for a phosphotransferase system sugar transporter (PTS).[3][8] The PTS is a multicomponent system discovered by Saul Roseman in 1964. The PTS involves enzymes of the plasma membrane and in the cytoplasm.[8] It is used by bacteria for active transport to intake sugar using phosphoenolpyruvate (PEP) as the source of energy.[3][8] The only other known Thermotoga with a PTS sugar transporter is Thermotoga sp. RQ2.[8]


Thermotoga naphthophila RKU-10 and Thermotoga petrophila RKU-1 since both were discovered in the same area, they can provide the first information on gene distribution that occurs through horizontal gene transfer (HGT) in hydrothermal ecosystems.[9] Microbes in the order Thermotogales are used for chemical and food industrial processes due to their extreme thermophilic activity.[10]

Thermotoga naphthophila RKU-10 was used to clone the β-galactosidase gene which is classified as a member of the GH-42 family[11],.[12] Wallace et. al. (2015), used the β-galactosidase gene to alleviate gastrointestinal cancer drug toxicity by observing structures and inhibition of the β-Glucuronidases micro-biome which is associated with the gene in Thermotoga naphthophila.[12]


  1. ^ Y. Takahata; M. Nishijima; T. Hoaki & T. Maruyama (September 2001). "Thermotoga petrophila sp. nov. and Thermotoga naphthophila sp. nov., two hyperthermophilic bacteria from the Kubiki oil reservoir in Niigata, Japan". International Journal of Systematic and Evolutionary Microbiology. 51 (Pt 5): 1901–1909. doi:10.1099/00207713-51-5-1901. PMID 11594624.
  2. ^ a b c Blöchl, E.; Burggraf, S.; Fiala, G.; Lauerer, G.; Huber, R.; Segerer, A.; Stetter, K.O.; Völkl, P. (1995). "Isolation, taxonomy and phylogeny of hyperthermophilic microorganisms". World J Microbial Biotechnol. 11 (1): 9–16. doi:10.1007/BF00339133. PMID 24414408.
  3. ^ a b c d e f g h i j k l m n o p q r s t u v w x y z aa ab ac ad ae af ag ah ai aj Takahata, Y; Nishijima, M; Hoaki, T; Maruyama, T (2001-01-01). "Thermotoga petrophila sp. nov. and Thermotoga naphthophila sp. nov., two hyperthermophilic bacteria from the Kubiki oil reservoir in Niigata, Japan". International Journal of Systematic and Evolutionary Microbiology. 51 (5): 1901–1909. doi:10.1099/00207713-51-5-1901. PMID 11594624.
  4. ^ a b c "Database entry showing genome size". KEGG.Genome Net. Kyoto University Bioinformatics Center. March 15, 2017.
  5. ^ a b c d e Takahata, Y.; Nishijima, M.; Hoaki, T.; Maruyama, T. (2000). "Distribution and physiological characteristics of hyperthermo- philes in the Kubiki oil reservoir in Niigata, Japan". Appl Environ Microbiol. 66 (1): 73–79. doi:10.1128/aem.66.1.73-79.2000. PMC 91787. PMID 10618205.
  6. ^ Huber, R; Langworthy, T.A; Konig, H.; Thomm, M.; Woese, C.R.; Sleytr, U.B; Stetter, K.O (1986). "Thermotoga maritima sp. nov. represents a new genus of unique extremely thermo- philic eubacteria growing up to 90 mC". Arch Microbiol. 144 (4): 324–333. doi:10.1007/bf00409880.
  7. ^ Swithers, Kristen S.; DiPippo, Jonathan L.; Bruce, David C.; Detter, Christopher; Tapia, Roxanne; Han, Shunsheng; Saunders, Elizabeth; Goodwin, Lynne A.; Han, James (2011-10-15). "Genome Sequence of Thermotoga sp. Strain RQ2, a Hyperthermophilic Bacterium Isolated from a Geothermally Heated Region of the Seafloor near Ribeira Quente, the Azores". Journal of Bacteriology. 193 (20): 5869–5870. doi:10.1128/JB.05923-11. ISSN 0021-9193. PMC 3187219. PMID 21952543.
  8. ^ a b c d Bramley, H F; Kornberg, H L (1987-07-01). "Sequence homologies between proteins of bacterial phosphoenolpyruvate-dependent sugar phosphotransferase systems: identification of possible phosphate-carrying histidine residues". Proceedings of the National Academy of Sciences of the United States of America. 84 (14): 4777–4780. Bibcode:1987PNAS...84.4777B. doi:10.1073/pnas.84.14.4777. ISSN 0027-8424. PMC 305188. PMID 3299373.
  9. ^ "Home - Thermotoga naphthophila RKU-10". Retrieved 2017-04-04.
  10. ^ "Thermotoga". MicrobeWiki. Retrieved April 4, 2017.
  11. ^ Kong, Fansi; Wang, Yeqing; Cao, Shugui; Gao, Renjun; Xie, Guiqiu (2014-05-01). "Cloning, purification and characterization of a thermostable β-galactosidase from Thermotoga naphthophila RUK-10". Process Biochemistry. 49 (5): 775–782. doi:10.1016/j.procbio.2014.02.008.
  12. ^ a b Wallace, Bret D.; Roberts, Adam B.; Pollet, Rebecca M.; Ingle, James D.; Biernat, Kristen A.; Pellock, Samuel J.; Venkatesh, Madhu Kumar; Guthrie, Leah; O’Neal, Sara K. (2015-09-17). "Structure and Inhibition of Microbiome β-Glucuronidases Essential to the Alleviation of Cancer Drug Toxicity". Chemistry & Biology. 22 (9): 1238–1249. doi:10.1016/j.chembiol.2015.08.005. PMC 4575908. PMID 26364932.

Further reading[edit]

External links[edit]