PMC:2726924 / 17698-18252 JSONTXT

{"project":"2_test","denotations":[{"id":"19345691-15663944-62520796","span":{"begin":115,"end":117},"obj":"15663944"},{"id":"19345691-16475820-62520797","span":{"begin":552,"end":554},"obj":"16475820"}],"text":"Amyloid fibril preparation\nRecombinant wild-type β2m was expressed in Escherichia coli and purified to homogeneity.26 The recombinant wild-type protein contained all 99 residues plus the N-terminal methionine, and the single disulfide bond was oxidised. Fibrils were formed by incubation of the protein (0.3–0.5 mg/ml) for 2–8 weeks at pH 2.5 in 25 mM sodium phosphate and 25 mM sodium acetate buffer containing 0.03% (wt/vol) sodium azide at 37 °C. At pH 7.0, fibrils were grown by elongation of heparin-stabilised seeds from fibrils formed at pH 2.5.24"}