Figure 4: The two cardiac MD::GFP molecules in the asymmetric unit for both the Apo and the OM+ structures differ in the rotation of the LAH and GFP.
From: Structural basis for drug-induced allosteric changes to human β-cardiac myosin motor activity
In both structures, the B chain converter domains, LAH and GFP, are rotated ∼15° from the near-rigour configuration towards the pre-power stroke state. (a) The core MD (residues 2–708) of the Apo-A and B chains is aligned to show the rotation of the B chain converter domain and LAH (coloured tan). The A chain GFP domain is not shown for clarity. (b) The A and B chains of OM+ structure are similarly aligned and enlarged to show the rotation of the LAH. The A chain OM molecule is shown as a space-filling model in the centre of the image. The B chain converter domain and LAH are coloured tan. The arrows indicate the direction of rotation of the SH3-like domain, the LAH, the converter domain and the relay helix of the B chain relative to the A chain. The point of rotation in both structures is G708, immediately above OM and marked by an arrowhead in b. Perhaps as a consequence of the rotation, the B chain converter domains, LAH and GFP, are less well defined in both structures with higher crystallographic atomic displacement parameters.
