Fatty acid composition of Thermus aquaticus at different growth temperatures

✍ Scribed by Heinen, Wolfgang ;Klein, Harold P. ;Volkmann, Carol M.

• Publisher: Springer-Verlag
• Year: 1970
• Weight: 205 KB
• Volume: 72
• Category: Article
• ISSN: 0003-9276
• DOI: 10.1007/bf00409525

✦ Synopsis

An extreme thermophilie bacterium, recently isolated from hot springs at Yellowstone National Park by Brock and designated as Thermus aquaticus (Brock and Freeze, 1969) has been examined for its fatty acid composition. Cells were grown either at 80~ which is the maximum temperature we have used so far, or near their lower growth limits, at 50~ (Heinen and Klein, 1969). After growth at the desired temperature, cells were harvested, washed, and extracted for lipids. The extraction, purification of the crude lipid extract, saponification, and separation of the fatty acids followed the methods of Kates et al. (1966). Methods to identify the fatty acids by gas chromatography (using 20 per cent DEGS as the stationary phase), bromination procedures, and methods for determining de novo fatty acid synthesis, have been ~ described earlier (Klein, 1965). Mass spectra were obtained on a CEC-110 double-focusing mass spectrometer.

Cells grown at 80~ (Fig. 1) contained four major fatty acids and a number of minor components. On the basis of their retention times, these four acids were tentatively identified as saturated acids of the following chain length: peak 3, normal C15; peak 4, branched (iso?) Cls; peak 5, normal C16; and peak 6, branched (iso?) C1~. The latter accounted for almost half of the total fatty acid complement. The minor components were small amounts of saturated branched and normal C1~ fatty acids (peak 1 and 2, respectively) and traces of unidentified long-chain fatty acids. Bromination of the total acid samples resulted in no change in the gas chromatographic pattern, thus supporting the contention that no unsaturated fatty acids were present in these ceUs. Finally, mass