There are five types of compounds associated with the electron transport system. Three of these consist of enzymes whose coenzymes or prosthetic groups are known to be directly invovled in the transfer. They are: (1) Pyridine-linked dehydrogenases, which have either NAD+ or NADP+ as coenzymes; (2) Flavin-linked dehydrogenases, which are linked to flavin adenine di- nucleotides (FAD) or flavin mononucleotides [...]
The size, shape, and structural organization of mitochondria, as well as the number of these organelles per cell and their intracellular location, vary considerably depending on the organism, tissue, and physiological state of the cell examined. Some cells, usually unicellular organisms, contain a single mitochondrion. Figure 16-3 contains a photomicrograph of the single mitochondrion in the motile swarm spore of [...]
The exact mechanism that couples the energy of electron transfer to the phosphorylation of ADP remains somewhat speculative. However, at the present time the chemiosmotic-coupling hypothesis-proposed by P. Mitchell is a widely supported model. Since its initial proposal in 1961, the hypothesis has undergone modification by Mitchell and by others. For his contributions to the development of this model, Mitchell [...]