Effects of signermycin B on WalK cross-linking and autophosphorylation. (a) Autophosphorylated WalK(Sm)31-450 was treated with increasing concentrations of signermycin B (lane 2, 0 μM; lane 3, 20 μM; lane 4, 40 μM; lane 5, 80 μM; lane 6, 160 μM; lane 7, 320 μM; lane 8, 640 μM) and cross-linked with glutaraldehyde. Lane 1, autophosphorylated HK in the absence of glutaraldehyde and signermycin B (control). (b) WalK(Sm)31-450 was autophosphorylated in the presence of increasing concentrations of signermycin B (lane 1, 0 μM; lane 2, 20 μM; lane 3, 40 μM; lane 4, 80 μM; lane 5, 160 μM; lane 6, 320 μM; lane 7, 640 μM).