4G2U:
reference: Structure of Ostertagia ostertagi ASP-1: insights into disulfide-mediated cyclization and dimerization., Borloo J, Geldhof P, Peelaers I, Van Meulder F, Ameloot P, Callewaert N, Vercruysse J, Claerebout E, Strelkov SV, Weeks SD, Acta Crystallogr D Biol Crystallogr. 2013 Apr;69(Pt 4):493-503. doi:, 10.1107/S0907444912050019. Epub 2013 Mar 9. PMID: 23519657

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