Pyrobaculum igneiluti sp. nov., a novel anaerobic hyperthermophilic archaeon that reduces thiosulfate and ferric iron.
A novel anaerobic, hyperthermophilic archaeon was isolated from a mud volcano in the Salton Sea geothermal system in southern California, USA. The isolate, named strain 521T, grew optimally at 90 °C, at pH 5.5-7.3 and with 0-2.0 % (w/v) NaCl, with a generation time of 10 h under optimal conditions. Cells were rod-shaped and non-motile, ranging from 2 to 7 µm in length. Strain 521T grew only in the presence of thiosulfate and/or Fe(III) (ferrihydrite) as terminal electron acceptors under strictly anaerobic conditions, and preferred protein-rich compounds as energy sources, although the isolate was capable of chemolithoautotrophic growth. 16S rRNA gene sequence analysis places this isolate within the crenarchaeal genus Pyrobaculum. To our knowledge, this is the first Pyrobaculum strain to be isolated from an anaerobic mud volcano and to reduce only either thiosulfate or ferric iron. An in silico genome-to-genome distance calculator reported <25 % DNA-DNA hybridization between strain 521T and eight other Pyrobaculum species. Due to its genotypic and phenotypic differences, we conclude that strain 521T represents a novel species, for which the name Pyrobaculum igneiluti sp. nov. is proposed. The type strain is 521T (=DSM 103086T=ATCC TSD-56T).
Department of Biology, Pomona College, Claremont, CA 91711, USA.
Jerry Y
JY
Lee
Department of Biology, Pomona College, Claremont, CA 91711, USA.
Brenda
B
Iglesias
Department of Biology, Pomona College, Claremont, CA 91711, USA.
Caleb E
CE
Chu
Department of Biology, Pomona College, Claremont, CA 91711, USA.
Daniel J P
DJP
Lawrence
Department of Biology, Pomona College, Claremont, CA 91711, USA.
Edward Jerome
EJ
Crane Iii
D001482:Base Composition; D002140:California; D052837:Chemoautotrophic Growth; D019641:DNA, Archaeal / Q000235:genetics; D005227:Fatty Acids / Q000737:chemistry; D005290:Ferric Compounds / Q000378:metabolism; D009693:Nucleic Acid Hybridization; D010802:Phylogeny; D041543:Pyrobaculum / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D012623:Seawater / Q000382:microbiology*; D017422:Sequence Analysis, DNA; D013885:Thiosulfates / Q000378:metabolism
D019641:DNA, Archaeal; D005227:Fatty Acids; D005290:Ferric Compounds; D012336:RNA, Ribosomal, 16S; D013885:Thiosulfates; C092844:ferric oxyhydroxide