Hopanoids of the methylotrophic bacteriaMethylococcus capsulatusandMethylomonassp. as possible precursors of C₂₉and C₃₀hopanoid chemical fossils

As a result of periodic acid oxidation followed by sodium borohydride reduction, the bacteriohopanepolyols, of unknown structure, from the methylotrophic bacteria Methylococcus capsulatus and 3 Methylomonas species, release a C30 hopanoid, (22S)-hopan-29-ol, as major product, and traces of the C29 hopanoid adiantol. Large amounts of hopanoids with an ethyl side chain are commonly found in almost all types of sediments. It is therefore probable that these are chemical fossils of the hopanoids from ubiquitous methylotrophic bacteria.