[36] Euglena Cytochromes

Publisher Summary Several cytochromes can be isolated from Euglena species, for example, c 552 , c -type 556, b -type 561 (558 and 563), and a -type 605. Only cytochrome c 552 has been highly purified and fully characterized. In the course of purification procedure of cytochrome c 552 , wild-type strains of Euglena gracilis are grown in an illuminated vessel at room temperature (25 ° ), and harvested after maximum growth is achieved. The cells are washed once with 0.9% NaCl and after centrifugation, the cell paste is stored at –15 ° C until used. Mutant strains may contain reduced amounts of cytochrome c 522 when grown under these conditions. Dark-grown Euglena strains do not contain this cytochrome. There are several methods for the extraction of the cytochrome c 552 , for example, with sulfuric acid, with digitonin, freezing and thawing, sonication, and acetone treatment. The acetone treatment gives the highest yield of cytochrome c 552 . This method also provides a high yield of ferredoxin. The freezing and thawing method is also recommended for the extraction process, although the recovery is lower and the ferredoxin is decomposed.