Cultivation of Coryneform bacteria on n-alkanes produced trehalose lipids which were isolated and identified by 1H-n.m.r. spectroscopy and f.a.b.-mass spectrometry. Fatty acids were found as substituents at positions 2, 3, 4, and 2′ of the trehalose. On incubation up to 80 h, the trehalose lipids are associated mainly with the cell wall and only 10% are extracellular. After 80 h, the trehalose lipids are mainly extracellular. © 1991.