BIOINORGANIC CHEMISTRY A Short Course Second Edition

POTASSIUM-DEPENDENT MOLECULES 217

Figure 5.7 View of the K + ion channel, the pore helix, and helices S1 – S6, PDB: 1ORQ.
Visualized using CambridgeSoft Chem3D Ultra 10.0 with notations in ChemDraw
Ultra 10.0. (Printed with permission of CambridgeSoft Corporation.) (See color
plate)

S4, cyan

S1, red

S2

S5, red

G200

tyr199

gly198 val197

thr196

K+ ions

gly220

asp62

arg126 arg123

arg133

arg120 arg117

S3b, rose

S3a, rose

pore helix, red

S6, blue

Extracellular side

Intracellular side