The “Raman spectroscopic signature of life” is closely related to haem function in budding yeasts

Abstract

HEM1 gene encodes δ-aminolevulinate synthase that is required for haem synthesis. It is an essential gene for yeast survival. The Raman spectra of HEM1 knockout (hem1Δ) yeast cells lacks a Raman band at 1602 cm(-1) that has been shown to reflect cell metabolic activity. This result suggests that the molecule giving rise to the"Raman spectroscopic signature of life" is closely related to haem functions in the cell. High amount of squalene is also observed in the hem1Δ strain, which is another new discovery of this study.

Photobleaching of the resonance Raman lines of cytochromes in living yeast cells

“…The potential of Raman spectroscopy for characterization the cell activity was demonstrated recently by series of studies [20][21][22][23]. Another outstanding application of the Raman spectroscopy for cells is the studies of the Raman spectra of cytochromes [24][25][26][27][28][29][30][31][32][33].…”

Molecular pathology via IR and Raman spectral imaging

“…Second, Ra-SCP can also be carried out by collecting spectra from individual cells by not utilizing the high spatial resolution (by using longer wavelength excitation and lower numerical aperture objectives) and aiming the exciting laser beam at specific targets in the cell, typically the nucleus. This method is more labor intensive, but yields in relatively short time hundreds of spectra of selected cellular features that show enormous sensitivity toward many biochemical processes, such as the metabolic activity in live yeast cells [38,39]. For example, this approach has been used very successfully to follow stem cell differentiation [40][41][42], photochemical changes in melanosomes [43] or for the detection of circulating tumor cells in flow cytometry [16,17].…”

Micro Raman spectroscopy for NETosis detection

“…Because NETosis is the process of the programmed neutrophils cell death, growth of this “citrulline” peak indicates cell death is coming soon. In a sense, similar to Hiro‐o Hamaguchi's Raman spectroscopic signature of life , this peak in neutrophil's Raman spectrum could be called Raman spectroscopic signature of death.…”

“…Raman microspectroscopy is widely used in the studies of cell biology, microbiology, and medicine for optical analysis of biological objects at the cellular level . Raman microspectroscopy allows exploring intracellular transformations and their features and helps to understand the processes occurring in the cell when studying the properties of the selective interaction of reagents in the cell . Recently, achievements in Raman microspectroscopy have opened up new prospects for the rapid and sensitive detection of bacteria of various types …”