FIG. 2.

Physicochemical parameters, total cell counts, and MPN across the oxic-anoxic interface of the Urania basin. (A) Oxygen and sulfide concentrations; (B) sulfate, ortho-phosphate, and chloride concentrations; (C) total cell counts; (D) viable cell counts in anoxic media containing the amino acid mixture (solid bars) and in oxic media containing thiosulfate (cross-hatched bars). Only values for the media which yielded maximum MPN are shown. The percentages are percentages relative to the total cell count. The error bars indicate standard deviations.