TABLE 4.
The effect of mutants of Phormidium cytochrome f on their interaction with Phormidium PC in the presence of the Zn2+ ion
| Class* | Mutant† | Complexes formed per 1000 trajectories† | % WT | 10−8 × k2 (M−1 s−1)† |
|---|---|---|---|---|
| Q7E | 271 ± 3 | 121 | 66 ± 3 | |
| WT | 225 ± 5 | 100 | 57 ± 3 | |
| I | Complex formation ≥ 89% WT | |||
| E14A | 222 ± 5 | 99 | 56 ± 4 | |
| D42A | 211 ± 6 | 94 | 54 ± 3 | |
| D79A | 205 ± 5 | 91 | 53 ± 3 | |
| D199A | 198 ± 3 | 88 | 62 ± 3 | |
| D109A | 191 ± 4 | 85 | 49 ± 3 | |
| D108A | 181 ± 4 | 81 | 47 ± 3 | |
| II | Complex formation between 59 and 77% WT | |||
| E198A | 173 ± 2 | 77 | 45 ± 3 | |
| Q7R | 172 ± 5 | 76 | 45 ± 3 | |
| D63A | 168 ± 6 | 75 | 44 ± 3 | |
| E217A | 165 ± 3 | 73 | 43 ± 3 | |
| E125A | 161 ± 2 | 72 | 42 ± 3 | |
| E91A | 161 ± 6 | 72 | 42 ± 3 | |
| E92A | 161 ± 5 | 72 | 42 ± 3 | |
| E212A | 153 ± 6 | 68 | 41 ± 3 | |
| E34A | 152 ± 6 | 68 | 40 ± 3 | |
| D205A | 144 ± 4 | 64 | 38 ± 3 | |
| D187A | 139 ± 5 | 62 | 37 ± 3 | |
| E96A | 138 ± 6 | 61 | 37 ± 3 | |
| E192A | 132 ± 4 | 59 | 35 ± 3 | |
| III | Complex formation between 50 and 59% WT | |||
| E165A | 120 ± 1 | 53 | 32 ± 3 | |
| D188A | 119 ± 4 | 53 | 32 ± 3 | |
| D87A | 116 ± 3 | 52 | 32 ± 3 | |
| D122A | 112 ± 3 | 50 | 31 ± 3 | |
| IV | Complex formation between 44 and 48% WT | |||
| E95A | 105 ± 3 | 47 | 29 ± 3 | |
| E123A | 101 ± 2 | 45 | 28 ± 2 | |
| E86A | 100 ± 3 | 45 | 27 ± 3 | |
*
Class I: complex formation was >80% WT; class II: 59–77% WT; class III: 50–59% WT; and class IV: 44–48% WT. The effects on the rates of electron transfer were identical to those on complex formation.
†
The mutants were made as described in the Methods section. The number of complexes formed and the rates of electron transfer were calculated as described for Table 1 and in the Methods section.