Thermomicrobium, a New Genus of Extremely Thermophilic Bacteria JACKSON, THOMAS J. and RAMALEY, ROBERT F. and MEINSCHEIN, WARREN G.,, 23, 28-36 (1973), doi = https://doi.org/10.1099/00207713-23-1-28, publicationName = Microbiology Society, issn = 1466-5026, abstract= A new, extremely thermophilic bacterium from an alkaline hot spring in Yellowstone National Park is described. The organism is gram negative and occurs as pleomorphic rods, often appearing in pairs. It is an obligate aerobe and grows optimally at 70 to 75 C at a pH of 8.2 to 8.5 with a generation time of 5.5 h. When grown in culture, the organism has a very pronounced pink color due to cellular carotenoid pigments. The deoxyribonucleic acid base ratio as determined by cesium chloride density gradient ultracentrifugation was found to be 64.3 mol% guanine plus cytosine. Nutritional studies with the new organism demonstrated a more restricted growth in comparison to organisms belonging to the genus Thermus. In studies involving defined carbon sources, it was shown that the new organism grew well only on sucrose or glycerol when glutamate served as an additional nutritional source. The organism is regarded as belonging to a new genus, for which the name Thermomicrobium is proposed. This genus is placed in the family A chromobacteraceae. The type species of the new genus is Thermomicrobium roseum sp. nov., of which ATCC 27502 is the type strain., language=, type=