A major glycolipid, alpha-Galf(1-3)-alpha-Galp(1-6)-beta-GlcpNAcyl(1-2)-alpha-Glcp(1-1)-2-acylalkyldiol, is obtained from Meiothermus taiwanensis. This novel glycolipid is found only when the bacterium grows above 62 degrees C, which is significantly different from those from the same bacteria incubated at 55 degrees C. Terminal galactofuranoside and 1,2-alkyldiol lipids replaced galactopyranoside and glycerol lipids, respectively, under increased growth temperature. This variation is likely necessary for bacteria for keeping the stable outer membrane and surviving under extreme environments.