1W5H: An Anti-Parallel Four Helix Bundle.
reference: Coiled coils at the edge of configurational heterogeneity. Structural analyses of parallel and antiparallel homotetrameric coiled coils reveal configurational sensitivity to a single solvent-exposed amino acid substitution., Yadav MK, Leman LJ, Price DJ, Brooks CL 3rd, Stout CD, Ghadiri MR, Biochemistry. 2006 Apr 11;45(14):4463-73. PMID: 16584182

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