Azadithiolate cofactor

An azadithiolate cofactor is an anion with the formula NH(CH₂S)₂^2-. It is used as a cofactor in the [FeFe] hydrogenases, bacterial enzymes responsible for the reversible reduction of 2 H⁺ to H₂.^[1] As a cofactor, the two thiolate functional groups are bound to each of the two irons in the active site of the enzyme. The amine functional group serves as an acid/base to transfer H⁺ from the solution to the active site.

References

^ Berggren, G., Adamska, A., Lambertz, C., Simmons, T. R., Esselborn, J., Atta, A., Gambarelli, S., Mouesca, J.-M., Reijerse, E., Lubitz, W., Happe, T., Artero, V., Fontecave, M. "Biomimetic assembly and activiation of [FeFe]-hydrogenases" Nature 2013, vol. 499, 66 doi:10.1038/nature12239

[1] Berggren, G., Adamska, A., Lambertz, C., Simmons, T. R., Esselborn, J., Atta, A., Gambarelli, S., Mouesca, J.-M., Reijerse, E., Lubitz, W., Happe, T., Artero, V., Fontecave, M. "Biomimetic assembly and activiation of [FeFe]-hydrogenases" Nature 2013, vol. 499, 66 doi:10.1038/nature12239

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