Table 1.

Hyperthermophile diversity

Organism (references)Growth conditionsIsolation/habitatMetabolic properties
  Aquifex pyrophilus (152)85°C, pH 6.8, 3% NaClShallow MHTVc, Kolbeinsey Ridge, north off IcelandMicroaerophilic, strict chemolithoautotroph. H2, S0, and S2O32− serve as electron donors; O2 and NO3 serve as electron acceptors
  Thermocrinis ruber (147)80°C, pH 7.0–8.5, <0.4% NaClOctopus spring, YellowstoneChemolithoautotrophic microaerophile; grows chemoorganoheterotrophically on formate or formamide
  Thermotoga maritimaa (150)80°C, pH 6.5, 2.7% NaClHeated sea floors, Vulcano, Italy, and AzoresHeterotroph anaerobe. Grows on cabohydrates and proteins; H2 inhibits growth.
  T. neapolitana (24)77°C, pH 7.5Shallow marine hot spring, Naples, ItalyHeterotroph anaerobe; grows on glucose, sucrose, lactose, starch, and YEc; reduces S0 to H2S
  Thermotoga strain FjSS3-B.1 (153)80–85°C, pH 7.0Intertidal hot spring, Savusavu, FijiAnaerobe, chemoorganotroph; grows on carbohydrates, including glycogen, starch, and cellulose; produces acetate, H2, and CO2, does not reduce S0 or SO42−
Archaea: Crenarchaeota
  Sulfolobus shibatae (122)81°C, pH 3.0Acidic geothermal spring, Beppu, Kiushu Island, JapanAerobe; facultative chemolithoautotrophic growth by S0 oxidation; can grow on carbohydrates, YEc, and tryptone
  S. solfataricusb(383)87°CSolfataric fieldsHeterotroph; grows on carbohydrates
  S. islandicus(380)UnknownSolfataric fields, IcelandObligate heterotroph; grows on peptides and carbohydrates
  Stygiolobus azoricus (302)80°C, pH 2.5–3.0Solfataric fields, Sao Miguel Island, AzoresStrict anaerobe; grows chemolithoautotrophically on H2 by reducing S0to H2S; no growth by anaerobic S0 oxidation
  Acidianus infernus (301)90°C, pH 2.0, 0.2% NaClHot water, mud, and marine sediments at hot springs in Italy, the Azores, and the United StatesFacultative aerobe, obligate chemolithotrophic growth by S0 oxidation (aerobic) or by S0 reduction with H2 (anaerobic)
  A. ambivalens (106, 384)80°C, pH 2.5Solfataric source, Leirhnukur fissure, IcelandFacultative anaerobe, chemolithoautotroph; uses either S0 + O2 (yielding H2SO4) or S0 + H2 (yielding H2S) as energy source.
  Thermoproteus tenax (33, 382)88°C, pH 5.0Solfataric fields, IcelandAnaerobe, facultative chemolithoautotroph; heterotrophic growth on glucose, starch, glycogen, a few alcohols, a few organic acids, peptides, and formamide by S0 respiration; H2S required; produces acetate, isovalerate, and isobutyrate from peptone + S0
  T. neutrophilus (104, 295)85°C, pH 6.8Hot spring, IcelandAnaerobe, facultative autotroph; acetate >> succinate > propionate can be used as carbon sources
  T. uzoniensis (33)90°C, pH 5.6Uzon caldera, Kamchatka peninsulaAnaerobe; ferments peptides, producing acetate, isovalerate, and isobutyrate; S0 stimulates growth.
  Pyrobaculum islandicum (148)100°C, pH 6.0Geothermal power plant, IcelandAnaerobe, facultative heterotroph (growth on peptide substrates with S0, S2O32− sulfite,l-cystine, or oxidized glutathione as electron acceptors; grows chemolithoautotrophically on CO2, S0 + H2, (produces H2S)
  P. organotrophum (148)102°C, pH 6.0Solfataric fields, Iceland, Italy, and AzoresAnaerobe, obligate heterotroph; growth on peptide substrates with S0, l-cystine, or oxidized glutathione as electron acceptor
  P. aerophilumb (355)100°C, pH 7.0, 1.5% NaClShallow marine boiling-water holes, Iischia, ItalyGrows by aerobic respiration or by dissimilatory nitrate reduction; heterotrophic growth on peptide substrates, propionate, and acetate; autotrophic growth by H2 or S2O32− oxidation; S0inhibits growth
  Thermofilum pendens(376)85–90°C, pH 5.0–6.0Solfataric fields, IcelandHeterotrophic anaerobe, mildly acidophile; grows by S0 respiration on complex peptide substrates; requires S0, H2S, and a polar lipid fraction from T. tenax
  Desulfurococcus mobilis (381)85°C, pH 6.0Solfataric fields, IcelandStrict heterotrophic anaerobe; grows on peptide substrates; S0 respiration or fermentation
  D. amylolyticus (34)90–92°C, pH 6.4Thermal springs, Kamchatka peninsulaStrict heterotrophic anaerobe; grows on peptide substrates and polysaccharides; S0 stimulates growth
  Staphylothermus marinus (103)92°C, pH 4.5–8.5, 1–3.5% NaClHeated sea floor, Vulcano, ItalyStrict anaerobe; S0dependent; heterotrophic growth on complex organic substrates; produces CO2, acetate, isovalerate, and H2S
  Thermosphaera aggregans(146)85°C, pH 6.5, 0% NaClYellowstone, Obsidian poolHeterotrophic anaerobe (YE, AA mix, glucose); S0inhibits growth
  Pyrodictium occultum (276, 321,   322)105°C, pH 5.5, 1.5% NaClMarine solfataric fields, Vulcano, ItalyStrict anaerobe; autotrophic growth on H2 + CO2 + S0(produces H2S); in the presence of YE, can grow by reduction of S2O32−
  P. abyssi (276)97°C, pH 5.5, 0.7–4.2% NaClDeep-sea MHTV, Guaymas, Mexico; shallow MHTV, Kolbeinsey Ridge, north off IcelandAnaerobe, strict heterotroph; grows by fermenting carbohydrates, cell extracts, proteins, and acetate; produces CO2, isovalerate, isobutyrate, and butanol, reduces S0 and S2O32− in the presence of H2
  P. brockii (276, 322)105°C, pH 5.5, 1.5% NaClMarine solfataric fields, Vulcano, ItalyStrict anaerobe; autotrophic growth on H2+ CO2 + S0 (produces H2S); YE stimulates growth yield; Reduces SO32−, not S2O32−
  Hyperthermus butylicus (377)95–106°C, pH 7.0, 1.7% NaClMarine solfataric field, AzoresHeterotrophic anaerobe; uses peptide mixtures as carbon and energy sources; forms H2S from S0 + H2 as accessory energy source; produces CO2, l-butanol, acetate, phenylacetate, and hydroxyphenyl acetate
  Thermodiscus maritimus(104)85°C, pH 6.5Hot sea water, Vulcano, ItalyObligate autotroph
  Pyrolobus fumarii (28)106°C, pH 5.5, 1.7% NaClDeep-sea MHTV (3,650 m), Mid-Atlantic RidgeObligate H2-dependent chemolithoautotroph, grows by NO3, S2O32−, or O2 (0.3%) reduction; S0 and several organic nutrients inhibit growth; no growth at 85°C and below
  Aeropyrum pernixa (291)90–95°C, pH 7.0, 3.5% saltCoastal solfataric MHTV, JapanStrict aerobe, heterotroph; grows on complex peptide substrates; no H2S production
  Caldococcus litoralis (385)88°C, pH 6.4, 2.5% NaClShallow MHTV, Kurile IslandsStrict anaerobic chemoorganotroph; grows on complex peptide substrates and amino acids; S0 stimulates growth (reduced to H2S)
Archaea: Euryarchaeota
  Palaeococcus ferrophilus (329)83°C, pH 6.0, 4.7% sea saltDeep-sea MHTV, Ogasawa-Bonin Arc, JapanStrict anaerobic chemoorganotroph; grows on proteinaceous substrates in the presence of S0 or Fe2+
  Thermococcus aggregans(57)88°C, pH 7.0Guaymas basin, MexicoChemoorganotrophic strict anaerobe
  T. barophilus (233)85°C, pH 7.0, 2–3% NaClMHTV (3,550 m), Mid-Atlantic RidgeObligate heterotroph; S0 stimulates growth; obligate barophile at 95–100°C
  T. guaymasensis (57)88°C, pH 7.2Guaymas basin, MexicoChemoorganotrophic anaerobe
  T. celer (378)88°C, pH 5.8, 4% NaClShallow marine solfataric field, Vulcano, ItalyObligate heterotrophic anaerobe; grows on peptide substrates by S0respiration or by fermentation; NaCl required
  T. acidaminovorans (84)85°C, pH 9.0, 1–4% NaClShallow MHTV, ItalyObligate heterotroph; grows on amino acids as sole carbon and energy source; S0 stimulates growth
  T. chitonophagus (151)85°C, pH 6.7, 2% NaClDeep-sea MHTV, Guaymas, MexicoObligate heterotrophic anaerobe; grows on chitin, YE, and meat extract; produces H2 (H2S in the presence of S0), CO2, NH3, acetate, and formate
  T. barossii (89)82.5°C, pH 6.5–7.5, 1–4% NaClJuan de Fuca RidgeObligate heterotrophic anaerobe, grows on peptides; S0 required for growth
  T. litoralis(260)85°C, pH 6.0, 1.8–6.5% NaClMarine solfataras, Vulcano and Naples, ItalyObligate heterotrophic anaerobe; grows in complex peptide substrates; S0 stimulates growth
  T. profundus(186)80°C, pH 7.5, 2–4% NaClMHTV (1,400 m), Mid-Okinawa Trough, JapanObligate heterotrophic anaerobe; S0dependent; uses complex peptide substrates, starch, pyruvate and maltose
  T. stetteri (249)75°C, pH 6.5, 2.5% NaClMarine solfararic fields, Northern KurilsStrict anaerobe, S0 dependent; uses complex peptide substrates, starch, and pectin; production of CO2, acetate, isobutyrate, isovalerate, and H2S
  T. hydrothermalisb (117)85°C, pH 6.0 2–4% NaClDeep-sea MHTV, East Pacific RiseObligate heterotrophic anaerobe; grows on proteolysis products, AA mix, and maltose in the presence of S0
  Pyrococcus furiosusb (102)100°C, pH 7.0, 2% NaClMarine solfataric fields, Vulcano, ItalyObligate heterotrophic anaerobe; grows on peptide substrates and carbohydrates; S0stimulates growth, probably by detoxifying H2 (forming H2S)
  P. woesei(379)100–103°C, pH 6.0–6.5, 3% NaClMarine solfataras, Vulcano, ItalyObligate heterotrophic anaerobe (YE, peptides, PS); S0 respiration, no fermentation
  P. abyssi (95)96°C, pH 6.8, 3% NaClDeep-sea MHTV, North Fiji BasinObligate chemoorganotroph, fermenting peptide substrates; Produces CO2, H2, acetate, propionate, isovalerate, and isobutyrate; produces H2S in the presence of S0; facultative barophilic; NaCl required
  P. horikoshiia (119)98°C, pH 7.0, 2.4% NaClOkinawa Trough, western PacificObligate heterotrophic anaerobe; Trp auxotroph
  Archaeoglobus fulgidusa (316)83°C, pH 5.5–7.5Heated sea floor, Vulcano, ItalyStrict anaerobe; chemolithoautotroph in the presence of H2, CO2, and S2O32−; heterotrophic growth on formate, formamide, lactate, glucose, starch, and peptide substrates; produces traces of methane
  A. profundus(49)82°C, pH 4.5–7.5, 0.9–3.6% NaClDeep-sea MHTV, Guaymas, MexicoStrict anaerobe, mixotroph, requires H2 for growth; uses organic acids, YE, peptide substrates as carbon sources; electron acceptors include sulfate, S2O32−, and sulfite
  Methanococcus jannaschiia (167)85°C, pH 6.0, 2–3% NaClDeep-sea MHTV (2,600 m), East Pacific RiseAutotrophic anaerobe, methanogen; NaCl and sulfide required for growth
  M. vulcanius (165)80°C, pH 6.5, 2.5% NaClEast Pacific RiseAnaerobe, methanogen; growth stimulated by YE, selenate, and tungstate; reduces S0 in the presence of CO2 and H2
  M. fervens(165)85°C, pH 6.5, 3% NaClGuaymas Basin, MexicoAnaerobe, methanogen; growth stimulated by YE, selenate, and tungstate, Casamino Acids, and trypticase
  M. igneus (48)88°C, pH 5.7, 1.8% NaClShallow MHTV, Mid-Atlantic Ridge, north off IcelandAnaerobe, methanogen, obligate chemolitho- autotroph; S0 inhibits growth
  M. infernus(166)85°C, pH 6.5, 2.5% saltDeep-sea MHTV, Mid-Atlantic RidgeChemolithotroph, obligate anaerobe, methanogen, reduces S0; YE stimulates growth
  Methanothermus fervidus (323)83°C, pH 6.5Icelandic hot springAnaerobe, methanogen; requires YE to grow in artificial medium
  M. sociabilis (292)88°C, pH 6.5Continental solfatara fields, IcelandAnaerobic S-independent autotroph; methanogen
  Methanopyrus kandleri (149)98°C, pH 6.5, 1.5% NaClDeep-sea MHTV, Guaymas, MexicoStrict anaerobe chemolithoautotroph; methanogen
  • a Fully sequenced genomes.

  • b Genome sequencing in progress

  • c Abbreviations: MHTV, marine hydrothermal vent; YE, yeast extract; AA, amino acid.