Tetrahymanol from the phototrophic bacterium Rhodopseudomonas palustris: first report of a gammacerane triterpene from a prokaryote

Tetrahymanol, a rare triterpene from the gammacerane series, previously detected only in a few scattered eukaryotic taxa, has been isolated for the first time from the phototrophic bacterium Rhodopseudomonas palustris. This extends the significance of geochemical markers from this series, which are abundant in marine sediments and palaeohypersaline environments.