Nsp2 has a large positive surface. A The electrostatic surface of nsp2 (red, negatively charged; white, non-polar; blue, positively charged). Residues K111, K112, and K113 are shown particularly. B Emphasized charged details of three zinc finger structures (ZnF1, ZnF2, and ZnF3) by the electrostatic surface. Residues involved in binding Zn2+ are shown as stick models (C, orange; N, blue; S, yellow; O, red).