Fig. 2

Bex1 has the physical identity as an IDP. a The purification scheme to obtain the recombinant Bex1 protein. b Coomassie brilliant blue (CBB) staining of purified Bex1 protein. c Far-UV circular dichroism (CD) spectrum of the recombinant Bex1 protein at 10, 25 and 37°C. A typical random coil CD spectrum was detected for the Bex1 protein. The measurements of a typical structured protein, albumin, are shown for comparison. Θ, molar ellipticity. c Two-dimensional nuclear magnetic resonance (2D-NMR) spectrum of the ¹⁵N-labelled recombinant Bex1 protein. The ¹H-¹⁵N heteronuclear single quantum coherence (HSQC) spectrum was measured at pH 7.3 and 10, 25 and 37°C. The spectrum of a typical structured protein, ubiquitin, are shown for comparison. Signals observed around 6.8–7.6 ppm in Bex1 plots were derived from side-chain amide groups