CORALS peptide biosignature detection
downstream-application
Laser desorption mass spectrometry workflow for detecting and sequencing short peptides as candidate biosignatures on icy ocean worlds such as Enceladus, demonstrated on the CORALS spaceflight prototype: a pulsed UV laser source feeding an Orbitrap mass analyser at ultrahigh mass resolving power and accuracy. Targets the 3-mer and 4-mer peptides found enriched in the psychrophile Colwellia psychrerythraea, on the premise that life persisting in cryogenic extraterrestrial brines might converge on a similar set. Adding silicon nanoparticles raises ionisation efficiency and improves mass resolving power and accuracy by suppressing metastable decay, which is what makes peptide de novo sequencing feasible; protonated peptides, their dimers and metal adducts are all detected. Sequencing rather than database matching is the only option available here, since no reference proteome exists for an unknown organism.
| Kind | downstream-application |
| Deep learning | no |
| Acquisition | DDA |
| Application area | astrobiology |
Papers
- Detection of Short Peptides as Putative Biosignatures of Psychrophiles via Laser Desorption Mass Spectrometry (2023, Astrobiology, peer-reviewed)