Table 3.
Comparison of Heme Solvent Accessibility between A.thaliana Cyt c 6A and Cyt c 6 for Which Structures Have Been Determined with X-ray Crystallography
| solvent exposure Å2a | ||||
|---|---|---|---|---|
| Pdb code | E m,7(mV) | total heme | porphyrin ringe | |
| Cytochrome c 6A | ||||
| Arabidopsis thaliana wild-type | 2dge11 | 71b,d/94c,5 | 70.4 | 15.9 |
| I17A/G18A oxidized | 2ce05 | 83b·d/89c·5 | 78.9 | 21.6 |
| I17A/G18A reduced | 2ce15 | 79.6 | 20.6 | |
| I17A/G18A/V52Q oxidized | 2v07d | 168b·d | 97.2 | 19.8 |
| Cytochrome c 6 | ||||
| Arthrospira maxima | 1f1f32 | 314c,47 | 62.3 | 17.9 |
| Cladophora glomerata | 1ls948 | 355 b,48 | 60.9 | 11.2 |
| Chlamydomonas reinhardtii | 1cyi/1cyj31 | 370c,49 | 70.0 | 9.4 |
| Monoraphidium braunii | 1ctj16 | 358c,50 | 60.7 | 7.4 |
| Phormidium laminosum | 2v08d | 325b,d | 57.7 | 14.7 |
| Porphyra yezoensis | 1gdv51 | 52.1 | 10.1 | |
| Scenedesmus obliquus | ||||
| oxidized | 1c6o4 | 73.6 | 8.8 | |
| reduced | 1c6r4 | 67.4 | 12.0 | |
a Calculated with NACCESS.52 b Obtained by CV. c Potentiometric titration. d Present work. e Cβ, O1, and O2 atoms were excluded from the calculation.