FIG. 1.

Aerobic growth of S. oneidensis MR-1 (A), S. putrefaciens CN32 (B), and Shewanella sp. strain W3-18-1 (C) with NaH₂PO₄ (▪) or DNA (□) as the sole source of phosphorus. Approximately 5% of phosphorus-starved cultures were used as inocula for all strains. The DNA and NaH₂PO₄ · H₂O concentrations in M1 medium were 300 mg/liter and 133.6 mg/liter, respectively, to achieve a final P concentration of 30 mg/liter. DNA was sterilized by autoclaving with the medium. The time course for growth was inferred from the OD₆₀₀. The data points and error bars represent the means and standard deviations of triplicate cultures, respectively.