| Raman spectroscopy, DABITC-X-AAAARRGpra, X = 20 canonical amino acids | Eight reporter peaks were resolved at 1143, 1200, 1314, 1368, 1398, 1424, 1445, and 1601 cm⁻¹, designated P1–P8; P1 served as the internal calibrant for intensity and frequency |
|---|---|
| Raman spectroscopy, Phe against Gly, Arg, or Trp | The P1 calibrant was identical and the spectra differed across the P4–P7 envelope |
| Raman spectroscopy, canonical amino acids | Histidine showed the strongest intensity gain across P4–P6; proline showed the strongest intensity loss at P5; phenylalanine showed the largest frequency shifts at P5–P7 |
| Raman spectroscopy, phosphorylated residues | Phosphoserine, phosphothreonine, and phosphotyrosine each showed a strong intensity increase across P4–P6 relative to serine, threonine, and tyrosine; phosphoserine and phosphothreonine were nearly indistinguishable |
| Raman spectroscopy, citrulline, arginine, and glutamine | Citrulline was resolved from arginine, with glutamine as an isosteric neutral-amide reference |
| Raman spectroscopy, lysine series | Unmodified lysine and its three methylation states were separated from one another, and propionyl-, succinyl-, and glutaryl-lysine were distinguished |
Varun Dolia, Daniel K. Angell, Sofia Barros, Viplove Arora, Radhika Mehta, Geoffrey A. Lovely, Andrew C. Serino, Vivian Wang, Jacob Chamoun, Cooper Owen, Susan Klaeger, Jennie R. Lill, Nhat Vu, Jennifer A. Dionne, Jack Hu. “A single-reagent vibrational tag (VibeTag) for peptide sequencing via iterative N-terminal amino-acid identification.” ChemRxiv (). https://doi.org/10.26434/chemrxiv.15007902/v1
Values presented only in Raman spectra, heatmaps, or other plots or images were not transcribed. The supporting information is appended to the main paper