1MEK:
reference: Structure determination of the N-terminal thioredoxin-like domain of protein disulfide isomerase using multidimensional heteronuclear 13C/15N NMR spectroscopy., Kemmink J, Darby NJ, Dijkstra K, Nilges M, Creighton TE, Biochemistry 1996 Jun 18;35(24):7684-91. PMID: 8672469

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