1QMD:
reference: Characterisation of the calcium-binding C-terminal domain of Clostridium perfringens alpha-toxin., Naylor CE, Jepson M, Crane DT, Titball RW, Miller J, Basak AK, Bolgiano B, J Mol Biol 1999 Dec 3;294(3):757-70. PMID: 10610794

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