Exilispira thermophila gen. nov., sp. nov., an anaerobic, thermophilic spirochaete isolated from a deep-sea hydrothermal vent chimney.
A novel thermophilic, anaerobic bacterium, strain RASEN(T), was isolated from a deep-sea hydrothermal vent chimney sample collected in the Iheya North field, Okinawa Trough, Japan, at a water depth of 982 m. The cells were motile, Gram-negative and helical with hooked ends, 0.23-0.28x15-27 microm in size with an approximate wavelength of 1.1-1.5 microm. Growth of the strain was observed at 37-60 degrees C (optimum 50 degrees C), in 2.5-3.5 % (w/v) NaCl (optimum 2.5-3 % NaCl) and at pH 6.0-7.5 (optimum pH 7.0). The strain grew on yeast extract only of the substrates examined in this study. The G+C content of the genomic DNA was 27.1 mol%. Major fatty acids for the strain were C(16 : 0), C(18 : 1)(Delta9) trans, C(18 : 0) and C(18 : 1)(Delta9) cis. Based on comparative 16S rRNA gene sequence analysis, strain RASEN(T) formed a deeply branching lineage within the phylum Spirochaetes and had only low levels of sequence similarity with other species of the phylum (range of similarity 72.1-80.6 %). Hence, we propose the name Exilispira thermophila gen. nov., sp. nov. The type strain of Exilispira thermophila is strain RASEN(T) (=JCM 14728(T) =NBRC 103205(T) =KCTC 5595(T)).
Subground Animalcule Retrieval (SUGAR) Program, Extremobiosphere Research Center, Japan Agency for Marine-Earth Science and Technology (JAMSTEC), Yokosuka, Kanagawa 237-0061, Japan. imachi@jamstec.go.jp
Hiroyuki
H
Imachi
Sanae
S
Sakai
Hisako
H
Hirayama
Satoshi
S
Nakagawa
Takuro
T
Nunoura
Ken
K
Takai
Koki
K
Horikoshi
D015373:Bacterial Typing Techniques; D001482:Base Composition; D004269:DNA, Bacterial / Q000235:genetics; D005227:Fatty Acids / Q000737:chemistry; D005798:Genes, Bacterial; D020459:Genes, rRNA; D007564:Japan; D008969:Molecular Sequence Data; D010641:Phenotype; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D012623:Seawater / Q000382:microbiology*; D013144:Spirochaetales / Q000737:chemistry / Q000145:classification* / Q000235:genetics* / Q000302:isolation & purification; D014871:Water Microbiology
D004269:DNA, Bacterial; D005227:Fatty Acids; D012336:RNA, Ribosomal, 16S