Table 1. Sensor properties of the different MagFRET variants.
| Variant | 1st EF-h and sequence1 | 2nd EF-hand sequence1 | K d Mg2+/mM ± SE2 | D.R. Mg2+ binding event3 | K d,1 Ca2+/µM ± SE2 | D.R. 1st Ca2+ binding event3 |
| MagFRET-1 | DTDKDEAIDYHE | DREATGKITFED | 0.15±0.02 | 49% | 10±3.7 | 19% |
| MagFRET-2 | DTDKDDAIDYHE | DREATGKITFED | 0.35±0.03 | 33% | 15±9.8 | 3.1% |
| MagFRET-3 | ATDKDEAIDYHE | DREATGKITFED | 9.2±0.7 | 58% | 4500±243 | 66% |
| MagFRET-4 | DTEKDEAIDYHE | DREATGKITFED | 8.5±0.5 | 62% | 4500±311 | 64% |
| MagFRET-5 | DTDKDEDIDYHE | DREATGKITFED | 7.4±0.5 | 74% | 1600±116 | 49% |
| MagFRET-6 | DTDKEEEIDYHE | DREATGKITFED | 15±0.8 | 50% | 7900±786 | 55% |
| MagFRET-7 | DTDKDEAIDYHE | KREATGKITFED | 0.78±0.04 | 38% | 57±5 | 23% |
| MagFRET-8 | DTDKDEAIDYHE | DREATKKITFED | 0.89±0.06 | 56% | 36±5 | 25% |
1
Mutations introduced in the first or second 12-residue metal binding loops of HsCen3 are indicated in bold and are underlined.
2
The dissociation constant (K d) for each variant's Mg2+ and first Ca2+ binding event is indicated, together with the standard error (SE).
3
A binding event's dynamic range (D.R.) is defined as the difference in emission ratio between the unbound and fully metal bound form divided by the emission ratio in the unbound form, multiplied by 100%.