Low Temperature Spectroscopy of Cytochromes of Chemoautotrophic Organisms

Various metabolic states of chemoautotrophic organisms can be identified by corresponding reduction states of their cytochrome content. These reduction states of the cytochromes can easily be observed, qualitatively as well as quantitatively, by means of low temperature spectroscopy. Due to the inherent characteristics like high resolution and the requirement for only concentrations of light absorbing molecular species, this method permits insight in, until recently, unknown interactions of cytochromes of intact cells and of cytochrome containing cell fractions. Physical phenomena that are involved in the low temperature spectroscopy of cellular and particulate matter will be discussed. Special attention will be given to the biochemical interferences of the partially organic solvents as used in low temperature spectroscopy with the enzymic systems of living cells.