Isolation and characterization of Methanoculleus receptaculi sp. nov. from Shengli oil field, China.
Three strictly anaerobic, thermophilic methanogens (ZC-2T, ZC-3 and ZC-6) were isolated from Shengli oil field, China. The 16S rRNA gene sequences of the three strains were nearly identical, possessing > 99.8% sequence similarity. They also possessed high sequence similarity, 97.4%, to Methanoculleus palmolei strain INSLUZ(T) (97.4% and 97.5%, respectively), indicating that they represented a novel species within the genus Methanoculleus. Cells of strain ZC-2T were nonmotile cocci, 0.8-1.7 microm in diameter, and always occurred singly or in pairs. The three strains used H2/CO2 or sodium formate as substrates for methanogenesis but not sodium acetate, trimethylamine, monomethylamine, ethanol, dimethyl sulfide, isopropanol, isobutanol, butan-2-ol or H2/CO. Optimum growth of strain ZC-2T occurred in the presence of 0.2 M NaCl, pH 7.5-7.8 and temperature 50-55 degrees C with a specific growth rate of 0.084 h(-1). The mol% G+C content of the genomic DNA was 55.2 mol%. Based on these phenotypic and phylogenetic characteristics, strains ZC-2T, ZC-3 and ZC-6 are proposed to represent a novel species in the genus Methanoculleus and named Methanoculleus receptaculi sp. nov. The type strain is ZC-2T (CGMCC 1.5087T=DSM 18860T).
Cheng
Lei
L
Biogas Institute of Ministry of Agriculture, Chengdu, China.
Qiu
Tian-Lei
TL
Li
Xia
X
Wang
Wei-Dong
WD
Deng
Yu
Y
Yin
Xiao-Bo
XB
Zhang
Hui
H
D002681:China; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D019638:Methanomicrobiaceae / Q000737:chemistry* / Q000145:classification / Q000302:isolation & purification* / Q000502:physiology; D008969:Molecular Sequence Data; D010578:Petroleum / Q000382:microbiology*; D010802:Phylogeny; D014871:Water Microbiology
D004269:DNA, Bacterial; D010578:Petroleum