title: On the origin of the 1602 cm-1 Raman band of yeasts; contribution of ergosterol.
abstract: The 1602 cm(-1) Raman signature, which we call the "Raman spectroscopic signature of life" in yeasts, is a marker Raman band for cell metabolic activity. Despite the established fact that its intensity sensitively reflects the metabolic status of the cell, its molecular origin remained unclear. In this work, we propose ergosterol as the major contributor of the 1602 cm(-1) Raman signature. The theoretical isotope shift calculation for ergosterol agreed with previous observations. Furthermore, experiments showed that the Raman spectrum of ergosterol corresponds very well with the depleting spectral component in yeast that behaves together with the 1602 cm(-1) signature when the cells are under stress. This work implies that the 1602 cm(-1) Raman signature could serve as an intrinsic ergosterol marker in yeasts for the study of sterol metabolism in vivo and in a label-free manner, which could not be done by any other techniques at the current stage.
authors.affiliation: Department of Chemistry, School of Science, the University of Tokyo, 7-3-1, Hongo, Bunkyo-ku, Tokyo 113-0033 Japan.
authors.forename: Liang-da
authors.initials: LD
authors.lastname: Chiu
authors.forename: Françoise
authors.initials: F
authors.lastname: Hullin-Matsuda
authors.forename: Toshihide
authors.initials: T
authors.lastname: Kobayashi
authors.forename: Hajime
authors.initials: H
authors.lastname: Torii
authors.forename: Hiro-O
authors.initials: HO
authors.lastname: Hamaguchi
mesh_terms: D002725:Chloroform / Q000737:chemistry; D004875:Ergosterol / Q000737:chemistry*; D008928:Mitochondria / Q000737:chemistry; D012441:Saccharomyces cerevisiae / Q000166:cytology*; D013059:Spectrum Analysis, Raman
chemical_list: D002725:Chloroform; D004875:Ergosterol