Figure 1.

Functionally active chromate reductase is expressed on the surface of purified M13-phage_Gh-ChrR. (Panel A) Map of engineered pCDisplay-4 phagmid vector endcoding Gh-ChrR (green arrows) expressed as a fusion protein with Fos-Gh-ChrR and Jun-Gh-ChrR to facilitate dimerization following phage display. (Panel B) Kinietic reduction of chromate (monitored at 370 nm) by purified M13-phage_ChrR (red squares) in comparison to M13 helper phage (blue triangles).

Notes: Measurements involved purified phage (5 × 10¹⁰ pfu/mL) in 50 mM Tris-HCl (pH 7.4), 100 mM NaCl, 0.5 mM Cr₂O₄, and 0.1 mM NADH. Chromate reduction rates for M13-phage_Gh-ChrR (ΔOD_370nm = 0.006/min) are significantly increased in comparison to that observed for helper phage alone (ΔOD_370nm = 0.004/min) (P = 0.00015).