6BQ5:
reference: Crystal structure of thermospermine synthase from Medicago truncatula and substrate discriminatory features of plant aminopropyltransferases., Sekula B, Dauter Z, Biochem J. 2018 Feb 23;475(4):787-802. doi: 10.1042/BCJ20170900. PMID: 29367265

This OCA Structure page
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