Sweers et al. Nanoscale Research Letters 2011, 6:270 http://www.nanoscalereslett.com/content/6/1/270 Abbreviations AFM: Atomic force microscopy; SPI: single-point nanoindentation. Acknowledgements The authors thank Kirsten van Leijenhorst-Groener for protein expression and purification and Sissi de Beer for advice on HarmoniX. Authors’ contributions VS and MLB supervised the project, KKMS performed the research, and analyzed the results. KOW, MLB, and KKMS interpreted the results. All authors critically discussed the results and the manuscript. Competing interests The authors declare that they have no competing interests. Received: 7 December 2010 Accepted: 30 March 2011 Published: 30 March 2011 References 1. Dobson CM: Protein folding and misfolding. Nature 2003, 426:884-890. 2. Hoyer W, Antony T, Cherny D, Heim G, Jovin TM, Subramaniam V: Dependence of α-synuclein aggregate morphology on solutions conditions. J Mol Biol 2002, 322:383-393. 3. 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