Bacterial populations recorded in diverse sedimentary biohopanoid distributions

Bacteriohopanepolyols (BHPs) are membrane lipids produced by a wide range of prokaryotes, including many methanotrophs, methylotrophs, cyanobacteria, nitrogen fixing bacteria and purple non-sulfur bacteria. As a result of the taxanomic variation expressed by the producer organisms, BHPs offer great potential as molecular markers of bacterial populations and processes and can be used to fingerprint hopanoid-producing bacterial populations in modern environments as well as having the potential to provide a valuable record of past bacterial community structure. Here we show that the diversity of BHPs in many recent sedimentary environments is considerably more complex than previously envisaged and can be used to readily identify organic matter derived from diverse groups of organisms as well as environmentally significant bio- and geochemical processes. (C) 2007 Elsevier Ltd. All rights reserved.