6FTK:
reference: NMR Structure of the FIV gp36 C-Terminal Heptad Repeat and Membrane-Proximal External Region., Grimaldi M, Buonocore M, Scrima M, Stillitano I, D'Errico G, Santoro A, Amodio G, Eletto D, Gloria A, Russo T, Moltedo O, Remondelli P, Tosco A, Wienk HLJ, D'Ursi AM, Int J Mol Sci. 2020 Mar 16;21(6). pii: ijms21062037. doi: 10.3390/ijms21062037. PMID: 32188158

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