1X9O:
reference: A model of the acid sphingomyelinase phosphoesterase domain based on its remote structural homolog purple acid phosphatase., Seto M, Whitlow M, McCarrick MA, Srinivasan S, Zhu Y, Pagila R, Mintzer R, Light D, Johns A, Meurer-Ogden JA, Protein Sci. 2004 Dec;13(12):3172-86. PMID: 15557261

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