Below is the list of custom synthesized peptides by Celtek Biosciences and Biomatik that we used for synthesizing [4Fe-4S]-maquettes and then studying their redox properties and biomimetic activity.

### Bioinspired Radical SAM Peptides

M_{w} |
= | 1010.16 g mol^{-1} |
pI | = | 5.24 |

ε^{red.} |
= | 1490 M^{-1} cm^{-1} |
instability index | = | 70.73 |

charge | = | -2 (at pH 8) | more info … |

M_{w} |
= | 960.10 g mol^{-1} |
pI | = | 4.37 |

ε^{red.} |
= | 1490 M^{-1} cm^{-1} |
instability index | = | 78.62 |

charge | = | -1 (at pH 8) | more info … |

M_{w} |
= | 961.14 g mol^{-1} |
pI | = | 7.96 |

ε^{red.} |
= | 1490 M^{-1} cm^{-1} |
instability index | = | 32.83 |

charge | = | neutral (at pH 8) | more info … |

### Nascent Radical SAM Maquettes

M_{w} |
= | 695.85 g mol^{-1} |
pI | = | 5.5 |

ε^{red.} |
= | est. M^{-1} cm^{-1} |
instability index | = | 53.06 |

charge | = | -1 (at pH 8) | more info … |

M_{w} |
= | 612.69 g mol^{-1} |
pI | = | 5.5 |

ε^{red.} |
= | est. M^{-1} cm^{-1} |
instability index | = | 55.02 |

charge | = | -1 (at pH 8) | more info … |

M_{w} |
= | 860.03 g mol^{-1} |
pI | = | 5.50 |

ε^{red.} |
= | 1490 M^{-1} cm^{-1} |
instability index | = | 48.28 |

charge | = | -1 (at pH 8) | more info … |

M_{w} |
= | 775.87 g mol^{-1} |
pI | = | 5.50 |

ε^{red.} |
= | 1490 M^{-1} cm^{-1} |
instability index | = | 50.02 |

charge | = | -1 (at pH 8) | more info … |

M_{w} |
= | 718.82 g mol^{-1} |
pI | = | 5.50 |

ε^{red.} |
= | 1490 M^{-1} cm^{-1} |
instability index | = | 28.99 |

charge | = | -1 (at pH 8) | more info … |

### Nascent Ferredoxin Peptides

M_{w} |
= | 639.80 g mol^{-1} |
pI | = | 5.50 |

ε^{red.} |
= | est. M^{-1} cm^{-1} |
instability index | = | 121.99 |

charge | = | -1 (at pH 8) | more info … |

M_{w} |
= | 555.64 g mol^{-1} |
pI | = | 5.50 |

ε^{red.} |
= | est. M^{-1} cm^{-1} |
instability index | = | 43.83 |

charge | = | -1 (at pH 8) | more info … |

M_{w} |
= | 802.99 g mol^{-1} |
pI | = | 5.50 |

ε^{red.} |
= | 1490 M^{-1} cm^{-1} |
instability index | = | 107.99 |

charge | = | -1 (at pH 8) | more info … |

M_{w} |
= | 718.83 g mol^{-1} |
pI | = | 5.50 |

ε^{red.} |
= | 1490 M^{-1} cm^{-1} |
instability index | = | 39.6 |

charge | = | -1 (at pH 8) | more info … |

### Ferredoxin Control Peptides

M_{w} |
= | 1527.81 g mol^{-1} |
pI | = | 5.97 |

ε^{red.} |
= | 5500 M^{-1} cm^{-1} |
instability index | = | 76.83 |

charge | = | -1 (at pH 8) | more info … |

M_{w} |
= | 1495.75 g mol^{-1} |
pI | = | 5.98 |

ε^{red.} |
= | 5500 M^{-1} cm^{-1} |
instability index | = | 76.83 |

charge | = | -1 (at pH 8) | more info … |

*Note 1:* Isoelectric point (pI) corresponds to a pH value at which net charge of protein is zero.

*Note 2:* Given that the pK_{a} of the N-terminal is expected to be in the range of 6.8 and 9.1 [10.1038/srep43748], we considered the N-terminal to be non-protonated at pH = 8.0.

*Note 3:* Molar extinction coefficients (ε) for peptides without aromatic residues were estimated from the additivity of peptide carbonyl charge transfer bands at λ = 205 nm [PubMed 14907727, 10.1002/pro.2253].

*Note 4:* The instability index provides an estimate of the stability of your protein in a test tube [10.1093/protein/4.2.155]. A protein with instability index that is smaller than 40, is predicted as stable; a value above 40 predicts that the protein may be unstable.