Prebiotic Environmental Conditions Impact the Type of Iron‐Sulfur Cluster Formed

Iron‐sulfur clusters are ancient cofactors that could have played a role in the prebiotic chemistry leading to the emergence of protometabolism. Previous research has shown that certain iron‐sulfur clusters can form from prebiotically plausible components, such as cysteine‐containing oligopeptides. However, it is unclear if these iron‐sulfur clusters could have survived in prebiotically plausible environments. To begin exploring this possibility, we tested the stability of iron‐sulfur clusters coordinated to a tripeptide and to N‐acetyl‐L‐cysteine methyl ester in a variety of solutions meant to mimic prebiotically plausible environments. We also assessed the impact of individual chemical components on stability. We find that iron‐sulfur clusters form over a wide variety of conditions but that the type of iron‐sulfur cluster formed is strongly impacted by the chemical environment and the coordinating scaffold. These findings support the general hypothesis that iron‐sulfur clusters were present on the prebiotic Earth and that different types of iron‐sulfur cluster predominated in different environments.