FIG 1.

S. aureus can use a variety of phosphorylated molecules as phosphate sources. A library of 58 phosphorus-containing compounds, including inorganic molecules (gray), carbohydrates (blue), amino acids (orange), and nucleotides (purple), was screened for the growth of S. aureus in defined, phosphate-depleted medium buffered to pH 7.4. Bacteria were precultured overnight in a P_i-limiting medium. Growth was monitored by assessing optical density at 600 nm (OD₆₀₀), and endpoint growth after 10 h is reported. The screen was performed in biological triplicate; error bars indicate standard deviations. An OD₆₀₀ of >0.1 (red dotted line) was used as the threshold to define phosphate sources that support growth. The black dotted line delineates growth on the positive control, P_i. The green dotted line denotes 75% of the growth on the positive control, used as the threshold to define good phosphate sources.