Figure 3

Structure of the MDC hetero-tetramer. a Schematic drawing of the structure of the MDC hetero-tetramer. The two domains of MdcA, AN and AC, are shown in yellow and orange, respectively. MdcC is shown in light blue, MdcD in cyan, and MdcE in green. The side chain of Ser25 in MdcC, the site of attachment of the prosthetic group, is shown as a stick model. A malonate bound in the active site of MdcA is shown as a sphere model (black) and labeled Mal. The bound position of CoA is also indicated (gray). The two active sites are indicated with the red asterisks, and the direct distance between them indicated with the red arrow. b Structure of the MDC hetero-tetramer, after 90° rotation around the vertical axis from a. c Structure of MdcA. d Structure of MdcC. e Molecular surface of MdcC colored based on sequence conservation⁵⁰. Purple: highly conserved, cyan: poorly conserved. The view is related to that of d after a 90° rotation around the vertical axis