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Biophysical Journal, Volume 74, Issue 6, 1 June 1998, Pages 3250-3255
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AbstractWith (resonance) Raman microscospectroscopy, it is possible to investigate the chemical constitution of a very small volume (0.5 fl) in a living cell. We have measured resonance Raman spectra in the cytoplasm of living normal, myeloperoxidase (MPO)-deficient, and cytochrome -deficient neutrophils and in isolated specific and azurophilic granule fractions, using an excitation wavelength of 413.1nm. Similar experiments were performed after reduction of the redox centers by the addition of sodium dithionite. The specific and azurophilic granules in both redox states appeared to have clearly distinguishable Raman spectra when exciting at a wavelength of 413.1nm. The azurophilic granules and the cytochrome -deficient neutrophils showed Raman spectra similar to that of the isolated MPO. The spectra of the specific granules and the MPO-deficient neutrophils corresponded very well to published cytochrome spectra. The resonance Raman spectrum of the cytoplasmic region of normal neutrophilic granulocytes could be fitted with a combination of the spectra of the specific and azurophilic granules, which shows that the Raman signal of neutrophilic granulocytes mainly originates from MPO and cytochrome , at an excitation wavelength of 413.1nm.
Abstract | Full Text | PDF (178 kb) - Continuous flow-resonance Raman spectroscopy of an intermedi...Continuous flow-resonance Raman spectroscopy of an intermediate redox state of cytochrome C
Biophysical Journal, Volume 38, Issue 2, 1 May 1982, Pages 111-116
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Biophysical Journal, Volume 95, Issue 9, 1 November 2008, Pages 4448-4455
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Abstract | Full Text | PDF (362 kb) - …more
Copyright © 1983 The Biophysical Society. All rights reserved.
Biophysical Journal, Volume 43, Issue 2, 191-205, 1 August 1983
doi:10.1016/S0006-3495(83)84340-9
Research Article
Intermediate and stable redox states of cytochrome c studied by low temperature resonance Raman spectroscopy
B. Cartling
Abstract
Stabilized intermediate redox states of cytochrome c are generated by radiolytic reduction of initially oxidized enzyme in glass matrices at liquid nitrogen temperature. In the intermediate states the heme group is reduced by hydrated electrons, whereas the protein conformation is restrained close to its oxidized form by the low-temperature glass matrix. The intermediate and stable redox states of cytochrome c at neutral and alkaline pH are studied by low-temperature resonance Raman spectroscopy using excitations in resonance with the B (Soret) and Q1 (beta) optical transitions. The assignments of the cytochrome c resonance Raman bands are discussed. The observed spectral characteristics of the intermediate states as well as of the alkaline transition in the oxidized state are interpreted in terms of oxidation-state marker modes, spin-state marker modes, heme iron--axial ligand stretching modes, totally symmetric in-plane porphyrin modes, nontotally symmetric in-plane modes, and out-of-plane modes.
