Fervidicoccus

Abstract

Fer.vi.do.coc'cus L. adj. fervidus hot; L. masc. n. coccus a berry and, in biology, a coccoid cell; N.L. masc. n. Fervidicoccus coccus that grows at high temperatures. Crenarchaeota / Thermoprotei / Fervidicoccales / Fervidicoccaceae / Fervidicoccus Members of the genus Fervidicoccus are extremely thermophilic, obligately anaerobic, and organotrophic microorganisms of the phylum Crenarchaeota . 16S rRNA genes of closely related microorganisms were found in environmental DNA samples from terrestrial hot springs of Kamchatka and Kuril Islands (Russia), Iceland, Yellowstone National Park (USA), and New Zealand with temperatures of 55–84°C, where they can make up a significant fraction of the microbial community. At present, the only cultivated representative of the Fervidicoccus genus is Fervidicoccus fontis, isolated from the Treshchinnyi hot spring of Uzon Caldera, Kamchatka. It is an anaerobic organotroph growing optimally on peptides in the presence of 20–50 mg/l yeast extract at 65–70°C and pH 6.0. Elemental sulfur, if present, is reduced to H 2 S; however, it is not obligately required for growth. H 2 partially inhibits the growth of Fervidicoccus fontis . Thus, phenotypically Fervidicoccus fontis resembles other anaerobic organotrophic archaea of the phyla Crenarchaeota and Euryarchaeota , such as desulfurococci and thermococci, but differs from them by its lower growth temperature. Complete genome analysis of Fervidicoccus fontis confirmed a distinct phylogenetic position of this group. DNA G + C content (mol%) : 37.5 (genome). Type species : Fervidicoccus fontis Perevalova, Bidzhieva, Kublanov, Hinrichs, Liu, Kolganova, Lebedinsky and Bonch‐Osmolovskaya 2010, 2086.