Table 2.
Effective radii of some physiologically significant inorganic and organic anions and osmolytes that potentially permeate anion channels.
| Anion | Effective radius (nm) | Reference |
|---|---|---|
| Cl− | 0.181 | [44] |
| NO3− | 0.212 | [44] |
| HPO42− | 0.275 | Unpublished calculation |
| Gluconate | 0.349 | [44] |
| Aspartate | 0.339 | Unpublished calculation |
| Glutamate | 0.345 | [44] |
| Taurine | 0.263 | [285] |
| Proline | 0.28 | [285] |
| Myo-inositol | 0.306 | [285] |
| Betaine | 0.285 | [285] |
| GPC | 0.367 | [285] |
| ATP4− | 0.57–0.58 | [212] |
| HATP3− | 0.56–0.58 | Unpublished calculation |
| MgATP2− | 0.59–0.61 | [212] |
| ADP3− | 0.53–0.56 | Unpublished calculation |
| UTP4− | 0.53–0.54 | Unpublished calculation |
The unhydrated radii were calculated as a geometric mean of three dimensions according to the formula: RX = (1 / 2) (l1l2l3)1/3 where l1, l2 and l3 are ion dimensions estimated from space-filling models. The dimension data were taken either from the indicated references or calculated using Molecular Modeling Pro computer software (Norgwyn Montgomery Software Inc., North Wales, PA).
GPC — Glycerophosphocholine.