1SR6:
reference: Myosin subfragment 1 structures reveal a partially bound nucleotide and a complex salt bridge that helps couple nucleotide and actin binding., Risal D, Gourinath S, Himmel DM, Szent-Gyorgyi AG, Cohen C, Proc Natl Acad Sci U S A 2004 Jun 15;101(24):8930-5. Epub 2004 Jun 7. PMID: 15184651

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