Plasma membrane b-type cytochromes.- NAD(P)H-utilizing flavo-enzymes in the plant plasma membrane.- Components and organisation of the NADPH oxidase of phagocytic cells, the paradigm for an electron transport chain across the plasma membrane.- Plasma membrane-bound nitrate reductase in algae and higher plants.- NADH oxidase: a multifunctional ectoprotein of the eukaryotic cell surface.- Iron transport in yeast: the involvement of an iron reductase and oxidase.- Reduction and uptake of iron in plants.- Involvement of plasma membrane redox systems in growth control of animal and plant cells.- Possible sources of reactive oxygen during the oxidative burst in plants.- Antioxidative role of ubiquinone in animal plasma membrane.- Metal reduction by macrophages: Its role in low-density lipoprotein oxidation.- Plasma membrane protein disulfide isomerase: its role in the translocation of diphtheria toxin and HIV virus across endosomal and cell membranes.- Plasma membrane redox systems in tumor cells.

Oxidation-reduction (i.e. redox) processes at the plasma membrane of any cell have been attracting more and more attention, both in basic and in applied research, since the first workshop dealing with the plasma membrane oxidoreductases was organized in Cordoba, Spain, in 1988. This evolution is evident considering the numerous cell functions performed by plasma membrane redox systems not only in healthy cells but also in cells that escaped from the normal metabolic control (e.g. cancer cells) and cells under attack by pathogens. Plasma membrane redox processes have now been demonstrated to play an essential role in growth control and defense mechanisms of these cells. The great importance of the plasma membrane redox systems originates in the fact that they are located in the membrane which is essentially the site of communication between the living cell and its environment. We may say that the plasma membrane can be considered as the "sensory part" of the cell. No chemical substance can enter the cell interior without interaction with the plasma membrane.