Probing Methionine Uptake in Live Cells by Deuterium Labeling and Stimulated Raman Scattering

J Phys Chem B. 2022 Mar 3;126(8):1633-1639. doi: 10.1021/acs.jpcb.1c08343. Epub 2022 Feb 23.

Abstract

The small biomolecule methionine (Met) is a fundamental amino acid required for a vast range of biological processes such as protein synthesis, cancer metabolism, and epigenetics. However, it is still difficult to visualize the subcellular distribution of small biomolecules including Met in a minimally invasive manner. Here, we demonstrate stimulated Raman scattering (SRS) imaging of cellular uptake of deuterated methionine (d8-Met) in live HeLa cells by way of comparison to the previously used alkyne-labeled Met analogue─homopropargylglycine (Hpg). We show that the solutions of d8-Met and Hpg have similar SRS signal intensities. Furthermore, by careful image analysis with background subtraction, we succeed in the SRS imaging of cellular uptake of d8-Met with a much greater signal intensity than Hpg, possibly reflecting the increased and minimally invasive uptake kinetics of d8-Met compared with Hpg. We anticipate that d8-Met and other deuterated biomolecules will be useful for investigating metabolic processes with subcellular resolution.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acids / metabolism
  • Deuterium / chemistry
  • HeLa Cells
  • Humans
  • Methionine*
  • Spectrum Analysis, Raman* / methods

Substances

  • Amino Acids
  • Methionine
  • Deuterium