ABSTRACT
This chapter summaries the questions yet to be answered in the field of cytochrome b structure and functions, and the applications toward which the research is leading us. Even with so many open research questions to still be addressed, applications of the knowledge rapidly accumulating in this area are becoming apparent. In the forefront of potential applications is the development of strategies for prevention of and therapy for acquired immunodeficiency syndrome (AIDS). The sensor is preferentially in the cytoplasmic membrane in order that it may respond to external stimuli before lethal or irreversible internal damage is experienced. NADPH oxidase has both membrane and cytoplasmic components, making it a good candidate for the sensor. The redox sensor activation must precede the release or mobilization of calcium. The fact that such processes are operational in photosynthesis and in electron transfer in mitochondria strongly suggests that developing an ideal "lossless" sensor is a goal toward which evolution is being driven.
