FIG. 1.

Relationship between cell density and MeHg production. (a) OD versus cell density; (b) OD in dilutions of a culture of D. propionicus versus final MeHg concentration. Spike concentration was 800 ng of Hg liter⁻¹, and cultures were incubated for 4 h. The culture dilutions were not duplicated; lines represent the best fit determined by linear regression of the data, r² = 0.98.