2HPP:
reference: Structures of the noncovalent complexes of human and bovine prothrombin fragment 2 with human PPACK-thrombin., Arni RK, Padmanabhan K, Padmanabhan KP, Wu TP, Tulinsky A, Biochemistry 1993 May 11;32(18):4727-37. PMID: 8387813

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