title: Ecology of sulfur-oxidizing bacteria in hot acid soils.
abstract: Hot acid soils in Yellowstone National Park are rich in elemental sulfur and harbor extensive populations of sulfur-oxidizing bacteria. Thiobacillus thiooxidans is found at temperatures below 55 C, and at temperatures from 55 to 85 C Sulfolobus acidocaldarius is present. The distribution of these bacteria as a function of temperature was measured by a most-probable-number dilution method, and their activity in situ was assessed by use of a new technique permitting measurement of (14)CO(2) fixation. From these data it is concluded that sulfur-oxidizing bacteria are responsible for production of sulfuric acid in these acidic thermal habitats. Physical and chemical parameters of this unusual soil habitat were also measured and are described.
mesh_terms: D013856:Acidithiobacillus thiooxidans / Q000254:growth & development / Q000302:isolation & purification / Q000378:metabolism; D001419:Bacteria / Q000254:growth & development / Q000302:isolation & purification / Q000378:metabolism*; D001431:Bacteriological Techniques; D002245:Carbon Dioxide / Q000378:metabolism; D002247:Carbon Isotopes; D004463:Ecology; D006358:Hot Temperature; D006863:Hydrogen-Ion Concentration; D012988:Soil Microbiology; D013455:Sulfur / Q000378:metabolism*; D013464:Sulfuric Acids / Q000096:biosynthesis; D013855:Thiobacillus; D014959:Wyoming
chemical_list: D002247:Carbon Isotopes; D013464:Sulfuric Acids; D002245:Carbon Dioxide; D013455:Sulfur