Fig. 3.

Conformational alterations of AtHIRD11 by metals. (A) Circular dichroism (CD) analyses using AtHIRD11 with different concentrations of Cu²⁺. AtHIRD11 alone (4.6 µM) is shown by a grey broken line. The [AtHIRD11]:[Cu²⁺] ratios are 1:0.5 (4.6 µM:2.3 µM, grey solid line), 1:5 (4.6 µM:23 µM, black broken line), and 1:50 (4.6 µM:230 µM, black solid line). Values are means of four measurements. (B) Effects of different metal cations on conformational changes of AtHIRD11. CD values at 200nm are compared. The white column showing the value without metal (NM) is standardized (100%). The [AtHIRD11]:[Cu²⁺] ratios are 1:0.5 (light grey columns), 1:5 (dark grey columns), and 1:50 (black columns). The concentrations of AtHIRD11 and Cu²⁺ were the same as in A. (C) Composition of secondary structures in AtHIRD11 as predicted by DICHROWEB (http://dichroweb.cryst.bbk.ac.uk/html/home.shtml). H1, H2, S1, S2, T, and U indicate regular helix, distorted helix, regular β-strand, distorted β-strand, turn, and unordered contents, respectively. The white columns represent the value without metal. The [AtHIRD11]:[Cu²⁺] ratios are 1:0.5 (light grey columns), 1:5 (dark grey columns), and 1:50 (black columns). The concentrations of AtHIRD11 and Cu²⁺ were the same as in A. In B and C, values and bars indicate means and SD of four measurements, respectively. *Significant differences (P < 0.05) in comparison with the value without metal were determined by Student’s t-test.