Native gel electrophoresis (7% polyacrylamide) of the wild-type and altered adenylosuccinate lyases to examine molecular weight and conformation. Only the adenylosuccinate lyases are shown in this figure: (1) wild type, (2) M10L, (3) I123R, (4) I123W, (5) T367R, and (6) T367S. As calculated from the major bands, the molecular masses are 209 kD, 220 kD, 223 kD, 246 kD, and 202 kD, respectively. (Molecular mass standards not shown.)