Investigating the effects of double mutation C30A/C75A on onconase structure: studies at atomic resolution Katarzyna Kurpiewska a* , Gerard Torrent b , Marc Ribó b , Joanna I. Loch a , Maria Vilanova b and Krzysztof Lewiński a a Faculty of Chemistry, Department of Crystal Physics and Crystal Chemistry, Protein Crystallography Group, Jagiellonian University, Ingardena 3, Kraków, 30060, Poland b Facultat de Ciències, Departament de Biologia, Laboratorid’Enginyeria de Proteїnes, Universitat de Girona, Maria Aurèlia Capmany 69, Campus de Montilivi, Girona, 17071, Spain *Corresponding author: kurpiewska@chemia.uj.edu.pl address: Faculty of Chemistry, Jagiellonian University, Ingardena 3, 30060, Kraków, Poland telephone: ++48 12 663 29 21 fax: ++ 48 12 634 05 15 Abbreviations: dmONC– double mutant C30A/C75A onconase ONC – onconase RI– ribonuclease inhibitor r.m.s. – root mean square RNase 1– human pancreatic ribonuclease A RNase A– bovine pancreatic ribonuclease A wtONC– wild type onconase Biopolymers This article has been accepted for publication and undergone full peer review but has not been through the copyediting, typesetting, pagination and proofreading process which may lead to differences between this version and the Version of Record. Please cite this article as an ‘Accepted Article’, doi: 10.1002/bip.22403 © 2013 Wiley Periodicals, Inc.