Data from: Elemental content and stoichiometry of SAR11 chemoheterotrophic marine bacteria

We measured the carbon, nitrogen, and phosphorus content and production of
cultured SAR11 cells in the genus Pelagibacter, from members of the 1a.1
and 1a.3 lineages, which are adapted to productive coastal waters and
oligotrophic tropical/subtropical environments, respectively. The average
growing SAR11 cell contained ~6.5 fg C, from which we calculated a global
standing stock of 1.4 1013 g C. Calculations that consider uncertainties
in cell turnover rates and growth efficiencies indicate this stock could
oxidize 6 to 37% of gross ocean primary production. We also found that
SAR11 do not incorporate 3H-thymidine, but do incorporate 3H-leucine. We
estimate conversion factors of 0.74 - 1.51 kg C mol-1 leu, which are
comparable to the low end of published leucine conversion factors for
marine chemoheterotrophic bacterioplankton production. The molar ratio of
elements C:N:P in growing cells was on average 25:6:1, significantly less
than the mean (~50:10:1) for heterotrophic bacteria, indicating these
strains are C and N poor relative to P.