Fervidobacterium thailandense sp. Nov., an extremely thermophilic bacterium isolated from a hot spring

Identifier:  PC:2547

Handle: https://hdl.handle.net/20.500.11797/PC2547

Authors:  Maria Carmen Portillo; Wirojne Kanoksilapatham; Patlada Pasomsup; Porranee Keawram; Alba Cuecas; Juan M. Gonzalez

Abstract:
Strain FC2004T, a strictly anaerobic, extremely thermophilic heterotroph, was isolated from a hot spring in Thailand. Typical cells of strain FC2004T were rod shaped (0.5–0.6×1.1–2.5 μm) with an outer membrane swelling out over an end. Filaments (10–30 μm long) and membrane-bound spheroids containing two or more cells inside (3–8 μm in diameter) were observed. The temperature range for growth was 60–88°C (optimum 78–80°C), pH range was 6.5–8.5 (optimum pH 7.5) and NaCl concentration range was 0 to <5 g l-1 (optimum 0.5 g l-1). S0 stimulated growth yield. S2O3 2– and NO3 - did not influence growth. Glucose, maltose, sucrose, fructose, cellobiose, CM-cellulose and starch were utilized for growth. The membrane was composed mainly of the saturated fatty acids C16:0 and C18:0. The DNA G+C content was 45.8 mol%. The 16S rRNA gene sequence of strain FC2004T revealed highest similarity to species of the genus Fervidobacterium: F. pennivorans DSM 9078T (97–96%), F. islandicum AW-1 (96%), F. changbaicum CBS-1T (96%), F. islandicum H21T (95%), F. nodosum Rt17-B1T (95%), F. riparium 1445tT (95%) and F. gondwanense AB39T (93%). Phylogenetic analysis of 16S rRNA gene sequences and average nucleotide identity analysis suggested that strain FC2004T represented a novel species within the genus Fervidobacterium, for which the name Fervidobacterium thailandense sp. nov. is proposed. The type strain is FC2004T (=JCM 18757T=ATCC BAA-2483T).