Short Communication Purification of C-Type Cytochromes from a Thermophilic Blue- Green Alga, Synechococcus vulcanus, by Hydrophobic Column Chromatography using Toyopearls

Two C-type cytochromes, c-550 and c-553, were extracted by an improved pro-cedure from a thermophilic blue-green alga, Synechococcus vulcanus, and effectively purified by a two-step hydrophobic chromatography. The first step was performed with a Toyopearl HW-65C:ammonium sulfate-66 column and the second with a butyl-Toyopearl 650 column. This work is the first to apply butyl-toyopearl 650 to protein purification. Key words: Cytochrome c-550 — Cytochrome c-553 — Hydrophobic chromato-graphy — Synechococcus vulcanus — Thermophilic blue-green alga — Toyopearl. Low molecular weight C-type cytochromes extracted and purified from a variety of algae have been extensively studied (Sugimura et al. 1968, Yakushiji 1971). These cytochromes have usually been obtained by conventional purification methods such as ammonium sulfate fractiona-tion, ion-exchange column chromatography and gel filtration. Although DEAE-cellulose is commonly used for ion-exchange column chromatography, in certain cases, cytochromes are not readily adsorbed on it and have to be chromatographed at very low salt concentrations (Koike and Katoh 1979, Ho et al. 1979). These cytochromes adsorbed not on a DEAE- but on a CM