title: Isolation and properties of the soluble c-type cytochromes of the dinoflagellate Peridinium cinctum.
abstract: Four soluble cytochromes of the c type were isolated from the freshwater dinoflagellate Peridinium cinctum collected from Lake Kinneret, Israel. Cytochrome c with alpha-band maximum at 550 nm in the reduced state had a molecular mass of 10,200 Da, pI 7.4, and Em of 278 m V. This cytochrome was active in the respiratory chain of beef heart Keilin-Hartree particles. Cytochrome c-553 had a molecular mass of 13,200 Da, pI 4.9, and Em of 384 m V, and was active in light induced electron transport of Euglena gracilis chloroplast fragments. Cytochrome c-554 had a molecular mass of 13,500 Da, pI 4.4, and Em of 326 m V. This cytochrome was inactive in light induced electron transport but competed with cytochrome c-552 of Euglena in the assay. The acidic cytochrome c-557 was present in very small quantities. The properties of the soluble c-type cytochromes of P. cinctum are compatible with the classification of dinoflagellates as primitive eucaryotes.
mesh_terms: D000818:Animals; D002417:Cattle; D002734:Chlorophyll / Q000378:metabolism; D003574:Cytochrome c Group / Q000302:isolation & purification*; D004141:Dinoflagellida / Q000201:enzymology*; D004579:Electron Transport; D005055:Euglena; D006736:Horses; D007527:Isoenzymes / Q000302:isolation & purification*; D007700:Kinetics; D008027:Light; D045342:Light-Harvesting Protein Complexes; D008929:Mitochondria, Heart / Q000201:enzymology; D010101:Oxygen Consumption; D045322:Photosynthetic Reaction Center Complex Proteins; D010940:Plant Proteins / Q000378:metabolism
chemical_list: D003574:Cytochrome c Group; D007527:Isoenzymes; D045342:Light-Harvesting Protein Complexes; D045322:Photosynthetic Reaction Center Complex Proteins; D010940:Plant Proteins; D002734:Chlorophyll