FIG. 2.

Regeneration of ATP from polyP and AMP as demonstrated by sustained bioluminescence from firefly luciferase (assay 2). (A) Effect of assay constituents on ATP regeneration activity. Complete reaction mixtures contained the following, except where otherwise indicated: cell extract protein at 0.5 mg/ml, 3 mM MgCl₂, AdK at 1 U/ml, polyP at 0.2 g/liter, and 2 mM AMP. Symbols: □, 1.0 μM ATP; ○, 10 μM ATP; ▸, complete reaction mixture; ■, complete reaction mixture without AMP; ◃, complete reaction mixture without AdK; ×, complete reaction mixture without polyP. (B) Demonstration of the polyP requirement for ATP regeneration (assay constituents as defined for panel A). Symbols: ◊, 10 μM ATP; ○, complete reaction mixture; □, complete reaction mixture without polyP; ■, complete reaction mixture without polyP but with polyP at 0.2 g/liter added at 30 min.