TABLE 4.

13C label incorporation into archaeal lipids during incubation in the presence of [13C]bicarbonateb

CultureThiosulfate (mM)Biphytane abundance (%)aBiphytane 13C atom (%)aAvg 13C in total lipids (%)
IIIIIIIVIIIIIIIV
SJ0.1381625214949494949
1.0451423184646464646
AR0.1451223204846474647
1.0371525234646464646
  • a Acyclic, monocyclic, bicyclic, and tricyclic biphytanes are indicated by I, II, III, and IV, respectively (see reference 68, but note that the structure of the tricyclic biphytane has been corrected since then [see reference 20]).

  • b After 1 day of complete oxidation of thiosulfate, 5 mM [13C]bicarbonate was added. Cells were harvested before ammonia was completely consumed.