Microbial Life at 90 C: the Sulfur Bacteria of Boulder Spring

作者：T. D. Brock, Melissa L. Brock, Thomas L. Bott, Mercedes R. Edwards · 发表于：Journal of Bacteriology · 年份：1971 · DOI：10.1128/jb.107.1.303-314.1971 · 被引用次数：106 · 研究领域：Methane Hydrates and Related Phenomena、Microbial Community Ecology and Physiology、Isotope Analysis in Ecology

The physiology of the bacteria living in Boulder Spring (Yellowstone National Park) at 90 to 93 C was studied with radioactive isotope techniques under conditions approximating natural ones. Cover slips were immersed in the spring; after a fairly even, dense coating of bacteria had developed, these cover slips were incubated with radioactive isotopes under various conditions and then counted in a gas flow or liquid scintillation counter. Uptake of labeled compounds was virtually completely inhibited by formaldehyde, hydrochloric acid, and mercuric bichloride, and inhibition was also found with streptomycin and sodium azide. The water of Boulder Spring contains about 3 mug of sulfide per ml. Uptake of labeled compounds occurs only if sulfide or another reduced sulfur compound is present during incubation. The pH optimum for uptake of radioactive compounds by Boulder Spring bacteria is 9.2, a value near that of the natural spring water (8.9). Many experiments with a variety of compounds were performed to determine the temperature optimum for uptake of labeled compounds. The results with all the compounds were generally similar, with broad temperature optima between 80 and 90 C, and with significant uptake in boiling (93 C) but not in superheated water (97 C). The results show that the bacteria of Boulder Spring are able to function at the temperature of their environment, although they function better at temperatures somewhat lower. The fine structure of these bacteria has been...