Occurrence of squalene and dehydrosqualene in streptomycetes

Squalene, dehydrosqualene and related hydrocarbons were found to constitute an essential part of the neutral lipid fraction extracted from mycelia and membranes of S. hygroscopicus, S. griseus and S. noursei. In comparison with the fraction of the triglycerides, these terpenoid compounds failed to incorporate (U-14C)-acetic acid throughout pulse labelling experiments. This suggested that the pertinent precursors were formed via alternative routes, for instance by catabolising branched-chain amino acids.