As shown in the following schematic representation the iron-sulfur cluster is bound by four conserved cysteine residues.

Analysis from crystallographic data suggests that HiPIP is capable of preserving its higher oxidation state by forming fewer hydrogen bonds with water.

The protein binds Fd via conserved CysXXCysXXCys structure (X stands for any amino acid).

[6] Also, the unique protein structure and dipolar interactions from peptide and intermolecular water contribute to shielding the [Fe4S4]3+ cluster from the attack of random outside electron donors, which protects itself from hydrolysis.

[7] HiPIPs take part in many oxidizing reactions in creatures, and are especially known with photosynthetic anaerobic bacteria, such as Chromatium, and Ectothiorhodospira.