TABLE 1.

Carbon fixed into bacterial biomass during experiment 2a

TreatmentμM 13C incorporated
Arsenate + sulfide200 ± 2
Arsenate alone50 ± 4
Sulfide alone68 ± 3
Filtered arsenate + sulfide5 ± 0.5
No added electron acceptors or donors46 ± 4
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  • a The amount of carbon fixed after 11 days of incubation (∼5 mM of arsenate reduced) was measured by incorporation of 13C supplied as bicarbonate. The values are means ± standard errors; n = 2.