The physiological reactions of mitochondria and chloroplasts can be reduced to a series of electron transfers, catalyzed by specific enzymes found within the organelles. Thus, we can study the component processes of photosynthesis and respiration by isolating the organelles and measuring specific enzyme activity associated with that organelle. - [Read Photosynthesis and Respiration - Introduction]
It is desirable to prepare subcellular fractions, either to localize proteins or to improve the sensitivity of protein detection. This procedure describes the enrichment of chloroplasts from Arabidopsis. - [Read Preparation of Arabidopsis Chloroplasts Protocol]