Abstract Raman microspectroscopy provides a powerful nondestructive means with high time, space and molecular specificity. We recently discovered a Raman band that sharply reflects the metabolic activity of mitochondria in a living S. Pombe cell and called it “the Raman spectroscopic signature of life” [1,2]. By using this signature, we are able to quantitatively trace the process of cell growth and death at the cellular level.

We also found [3] that this signature disappears concomitantly with a sudden appearance of a dancing body in a vacuole of a budding yeast (S. cerevisiae) cell and that the appearance of the dancing body necessarily results in a loss of the vacuole and, eventually, in an inevitable cell death. Molecular-level changes in organelles accompanying this spontaneous cell death process have been traced beautifully by time-resolved Raman imaging.

Recent developments in non-linear Raman imaging of living cells [4] will also be discussed.

References [1] Huang Y-S, Karashima T, Yamamoto M, Ogura T, Hamaguchi H. J. Raman Spectrosc. 35, 525 (2004). [2] Huang Y-S, Karashima T, Yamamoto M, Hamaguchi H. Biochemistry, 44, 10009 (2005). [3] Naito Y, To-e A, Hamaguchi H, J. Raman Spectrosc. 36, 837 (2005). [4] H. Kano and H. Hamaguchi: Appl Phys Lett 86, 121113 (2005); Opt. Express 13, 1322 (2005); Opt. Express, 14, 2798 (2006).