Isolation and fractionation of plant mitochondria and chloroplasts: Specific examples

This chapter discusses the isolation and fractionation of plant mitochondria and chloroplasts and underlines the peculiar mechanisms involved in the biosynthesis of mitochondria and chloroplast in plants, where the productive interaction of the three cellular genomes is required. Plant organelles have been studied for their unique metabolisms. The chapter describes general methods for the isolation and fractionation of plant mitochondria and chloroplasts. The methods have to be adapted for each specific purpose, and the chapter discusses some researchers' experience with problems derived from the use of different plant material. Even when working with a same plant species, for each specific purpose, the appropriate starting material must be chosen. Both mitochondria and chloroplasts are isolated from total plant extracts by differential centrifugation. The material obtained is contaminated with soluble hydrolases, other cellular fractions, membrane fragments, bacteria, and, in the case of mitochondria isolation, the presence of plastid material. © 1995, Academic Press, Inc.