3TC2:
reference: Structure of a post-translationally processed heterodimeric double-headed Kunitz-type serine protease inhibitor from potato., Meulenbroek EM, Thomassen EA, Pouvreau L, Abrahams JP, Gruppen H, Pannu NS, Acta Crystallogr D Biol Crystallogr. 2012 Jul;68(Pt 7):794-9. doi:, 10.1107/S090744491201222X. Epub 2012 Jun 15. PMID: 22751664

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