Probing single cells of purple sulfur bacteria with Raman spectroscopy: carotenoids and elemental sulfur
2015
Abstract
We explored the use of Raman spectroscopy to simultaneously monitor the presence of different biomarkers (carotenoids, elemental sulfur) within single cells of the purple sulfur photosynthetic bacteria Allochromatium vinosum and A. warmingii. Raman microspectrometry using excitation at 532 nm allowed the detection of different carotenoids.
Raman signals of elemental sulfur appeared soon after feeding starved cells with sulfide. Raman spectroscopy is thus a convenient and sensitive technique to qualitatively and semiquantitatively assess the presence of different compounds of interest within single bacterial cells.