Fig. 2
Crystal structures of β-cardiac myosin and description of the converter/ELC interface. a X-ray structure of β-cardiac myosin S1 complexed with MgADP in the post-rigor state (PR-S1). b Interface between the converter and the ELC as found in the PR state. This interface involves mainly electrostatic interactions between a cluster of negatively charged residues of the ELC (D136; E135 and E139) and positively charged residues of the heavy chain (R723 and R780). Side chains of interacting residues (sticks) and polar interactions (yellow lines) are represented. Four converter mutations studied in this work (R719W; R723G; I736T; G741R) are colored in light blue. c Structure alignment of converters of the Myosin 2 superfamily. MYH7: bovine (Bos taurus) β-cardiac myosin; ScMyo2: bay scallop (Argopecten irradians) Myosin 2; SqMyo2: longfin inshore squid (Dorytheutis pealeii) Myosin 2; SmMyo2: chicken (Gallus gallus) gizzard smooth muscle myosin 2. d Superimposition of several Myo2 converter structures: from PR-S1 colored in green; from SqMyo2 (PDB code 3I5F, pink); from SmMyo2 (PDB code 1BR1, orange); from ScMyo2 in the PPS (PDB code 1QVI, purple) and Rigor (PDB code 1SR6, cyan) states. e Location of the top loop (deep teal blue) and the side loop (sand yellow) in the cartoon representation of the crystal structure of the β-cardiac myosin PR-S1 (gray) with the converter colored in light green and the ELC colored in light pink. The top loop is part of the converter/ELC interface
