Biochemistry of the Phagocytic Process

whiclh will eventually be publislhed under a single cover. There are eight contributions to the present volume, whiclh provide useful summaries of the work of the various participants. The first paper, "Evidence for a membrane-linked Ca++ carrier in rat liver andI kidlney mitoclhondria," by A. L. Lehninger and E. Carafoli, is unrelated to the others. It concerns the dynamics of Ca++ movements coupled to the energy-conserving mechaniisms in mitochontdria, and summarizes evidence for tlle occurrence of a "permease" in the inner membrane of liver and kidney mitochondria. In "The oxidation of cytoclhrome c catalysed by cytochrome oxidase and horse-radisli and cytochrome c peroxidases," T. Yonetani et al. discuss recent stu(lies on the spin-labeled cytochrome c, and the mechaniism of the reactions cited in the title. In "The role of mammalian peroxidase in iodination reactions," M. M\Iorrison et al. review the peroxidlases in mammalian tissues and pOint out differences between thiem. These includle lactoperoxidase, found in salivary, lacri-mal, hardleriain and(I mammary glands; myeloperoxidase in granulocytes (and monocytes); thyroid peroxidase in the thyroid gland; and glutathione peroxidase, a widely distributed flavoprotein. In "Studies on the relationship of chloroperoxi-dase-lhalide and chloroperoxidase-lhydrogen peroxide complexes to the mechanism of the halogeniation-reaction," L. P. Hager et al. discuss a protolleme peroxi-dase whiclh is very similar to the lhorseradish and Japanese radish peroxidases in its plhysical and chemical properties. Their studies are directedl toward defining reactions that could produce an enzyme-bound lhalogenium ion as an active intermediate in the halogenation reaction. In "1\Iyeloperoxidase-mediated antimicrobial systems and their role in leulko-cyte functioni," S. J. Klebanoff describes the iodination of bacteria tllat have been ingested by human neutrophils in the presence of labeled iodide. This reaction is believedl to be largely a consequence of the reaction of myeloperoxidase, released into the phagocytic vacuoles as a result of granule rupture, with H202 formed during the leukocyte respiratory burst (or by microbial metabolism when a HO.2-generating organism is elmployed) and the added radioactive iodide. The reaction, in wlhiclh chloride can be substituted for iodide, appears to contribute to the antimicrobial activity of the leukocyte. Neutrophils from patients with chronic granulomatous disease of childhood, which do not generate normal amounts of H2O, during plhagocytosis of bacteria, cannot kill Staphylococcus aureits and various gram negative organisms normally, but can kill organisms that generate their own hydrogen peroxide such as streptococci and pneulmococci. The recurrent infections with staphylococci and gram negative organisms that these …