Table 1.

¹³Carbon enrichment of Methylosinus trichosporium OB3b cells grown on ¹³C-labeled methane with or without additional supplementation with unlabeled carbon dioxide.

Treatment	13C/12C ratio	Mean	Lower 95%	Upper 95%	Number of cells analyzed
13C-methane	0.351 ± 0.231	0.04	0.264	0.437	30
13C-methane + 12CO2 (5%)	0.134 ± 0.046	0.01	0.113	0.155	21

¹³C of cells grown on unlabeled ¹²CH₄ is 55.19 ± 0.21.