Fig. 4: Raman fingerprint of Gt-ABs.

a Confocal RS images representative of the 2 µm and 3–5 µm Gt-AB subpopulations. Every spectrum describes the biochemical features of individual Gt-ABs deposited and grouped on the gold mirror. Randomly selected areas were imaged. Scale bar corresponds to 20 µm. b Average Raman spectra obtained using an excitation wavelength of 405 nm and 10 s of exposure for 2 accumulations for each spectrum. The solid lines correspond to an average of at least 8 spectra per ABs subpopulation per growth stage ± the SEM (shaded areas). Green spectral lines correspond to ABs harvested in the stationary phase and black lines correspond to ABs of the death phase. Ranges of the spectral peaks are frequently reported and correspond to major constituents of biological samples. The Raman peaks indicating carbohydrates are highlighted in brown (370–430 cm⁻¹), nucleic acids in red (668–823 cm⁻¹), proteins in blue (1531–1641 and 1684–1697 cm⁻¹) and lipids in yellow (1750–1771 cm⁻¹). Peak intensity is given at the Y-axis (a.u.). Source data are provided as a Source data file.