BIOINORGANIC CHEMISTRY A Short Course Second Edition

POTASSIUM-DEPENDENT MOLECULES 219

Figure 5.8

Closed and opened views of the potassium ion channel pore according to reference 25. S4 helix of PDB: 1ORQ. Visualized

using CambridgeSoft Chem3D Ultra 10.0 with notations in ChemDraw Ultra 10.0. (Printed with permission of CambridgeSoft Corpora-tion.) (See color plate)

External Internal

ARG 126

ARG 126

ARG 123

ARG 117

ARG 123

ARG 117

Closed

External Internal

Opened

10 Å 15 Å 10 Å

10 Å 15 Å 10 Å