Are iron porphyrins stable enough to withstand ion bombardment?

Abstract

Porphyrin-type cofactors, especially hemes (iron porphyrins) occur in virtually all terrestrial organisms and are involved in basic metabolic processes. Therefore, hemes are regarded as evolutionary very old biomolecules. Furthermore, it has been speculated that molecules similar to heme could have also evolved on other planets or moons (Suo et al. 2007). Because of their aromaticity, porphyrins are generally very stable and can be easily detected with various analytical methods. These were among the reasons why porphyrins were presumed to be ideal biosignatures (Suo et al. 2007). However, abiotic syntheses for (metallo)porphyrins are now known (e.g., Fox and Strasdeit 2013; Pleyer et al., manuscript submitted). Consequently, these molecules may well be "false positive" biosignatures (Fox and Strasdeit 2017).