Desulfurococcaceae, the Second Family of the Extremely Thermophilic, Anaerobic, Sulfur-Respiring Thermoproteales

摘要: Summary Two novel species of anaerobic thermophilic archaebacteria isolated from acidic hot springs Iceland, Desulfurococcus mucosus and mobilis , representing a second family, termed Desulfurococcaceae the order Thermoproteales are described. They utilize yeast extract or casein its tryptic digest, but not casamino acids, as carbon sources, by sulfur respiration with production H 2 S CO fermentation. The pH optimum growth is 5.5 to 6, temperature 85 °C. archaebacterial nature evident their insensitivity towards vancomycin, streptomycin chloramphenicol, lack murein cell wall, presence phytanol polyisoprenoid dialcohols in lipids, composition properties DNA dependent RNA polymerase. closely related recently described thermoacidophilic sulfur-respiring Thermoproteus tenax first Thermoproteaceae . Of other divisions archaebacteria, Sulfolobus nearest relative. has slimy polymer attached envelope. possesses flagellae monopolar polytrichous arrangement.