Figure 1.

Chiralities of the disulfide bridge with χ_S−S torsional angle values of −90° (A) and +90° (B). Coloring: H—cyan, C—gray, O—red, N—blue, S—yellow, free electron pairs—magenta. In (A) distance relations leading to typical cross peaks in NOESY-type spectra are marked (small arrows). Distance relations originating either from the H^α (orange) or the H^β protons (green) are indicated only for one of the two cysteines. (C,D) Chemical shift correlation of cysteine C^β and H^β2 (C), H^β3 (D), respectively. Chemical shift data and correlations are obtained and visualized from the Biological Magnetic Resonance Data Bank (BMRB) using a modified PyBMRB python module. Distribution values which are outside 10 times the standard deviation were removed from each correlation data set. Contour levels reflect the total number of correlations within.