Hyperthermus

This is a curated page. Report corrections to Microbewiki.

A Microbial Biorealm page on the genus Hyperthermus

Electron micrographs of H. butylicus. Cells connected by a string of cytoplasm. From Zillig, W. et al. "Hyperthermus butylicus, a Hyperthermophilic Sulfur-Reducing Archaebacterium That Ferments Peptides." J. of Bacteriol. July, 1990. Vol. 172, No. 7. p. 3962.

Classification

Higher order taxa

Archaea; Crenarchaeota; Thermoprotei; Desulfurococcales; Pyrodictiaceae

Species

Hyperthermus butylicus

NCBI: Taxonomy Genome

Description and significance

Hyperthermus is a hyperthermophilic, sulfur reducing archaeon that grows between 95 and 106°C and at pH of 7.0. Also, it forms H₂S from elemental sulfur and molecular hydrogen as a growth-stimulating accessory energy source but not by sulfur respiration. Further, the archaeon has a characteristic smell which composes of H₂S and butyl mercaptan and the odors of 1-butanol and phenylacetic acid.

Genome structure

The genome of Hyperthermus has been completed by Brugger et al. Its genome consists of a single circular chromosome of 1,667,163 bp with a 53.7% G+C content. A total of 1672 genes were annotated, of which 1602 are protein-coding, and up to a third are specific to H. butylicus. A relatively high level of GUG and UUG start codons are predicted.

Cell structure and metabolism

The cells of Hyperthermus are irregular spherical shape (around 1.5 µm in diameter) with edges between partially flattened surfaces. The ones that grow in higher temperature often contain vacuoles within their cytoplasm, sometimes immediately below the S layer. The archaeon acquires energy by fermenting peptides, including laboratory peptide mixtures (eg, Tryptone, Trypticase, Merck peptone from casein, gelatin, and a chymotryptic digest of casein) as carbon and energy sources. No growth has been observed with starch, maltose, sucrose, lactose, glucose, galactose, ribose, lactic acid, lactic acid ethylester, glyoxylate, pyruvate, oxalate, fumarate, maleate, malate, malonate, and formate.

Ecology

The strains of Hyperthermus butylicus were isolated from the sea floor of a hot, solfataric habitat on the coast of São Miguel Island in Azores, Portugal. With its ability to live at the temperature of 106°C, it is one of the most thermophilic archaea isolated so far.

References

Brugger K, Chen L, Stark M, Zibat A, Redder P, et al.."The genome of Hyperthermus butylicus: a sulfur-reducing, peptide fermenting, neutrophilic Crenarchaeote growing up to 108 degrees C." 2007. Archaea 2:127-135.
Zillig, W., Holz, I., Janekovic, D., Klenk, H., Imsel, E., Trent, J., Wunderl, S., Fojaz, V. H., Coutinho, R., and Ferreira, T." 1990. Hyperthermus butylicus, a Hyperthermophilic Sulfur-Reducing Archaebacterium That Ferments Peptides." Journal of Bacteriology. 172:3959-3965.