Arachidonic acid undergoes iodination in the presence of hydrogen peroxide, iodide, and either eosinophil peroxidase, myeloperoxidase or lactoperoxidase. The profile of products generated by each of the three peroxidases is similar as determined by reversed-phase high-performance liquid chromatography. Structural analysis of the products indicate that: 1, each of the four double bonds in arachi...

Selective iodination at the alpha-pyrrole positions of dipyrrolyldiketone BF(2) complexes is a key procedure to afford mono- and bisiodinated derivatives as the starting materials of the coupling reactions for various utility molecules and covalently linked oligomer systems. Iodination can also be applied to the phenylene-bridging receptor dimer to obtain the derivatives selectively iodinated a...

Human salivary proteins were enzymically iodinated by the 125I-lactoperoxidase system. The proteins were than subjected to DEAE-cellulose column chromatography, preparative column electrofocusing and thin-layer polyacrylamide-gel electrofocusing. The radioactivity in the resolved protein pools and bands was determined. Results show that salivary proteins differ in their susceptibility to iodina...

Thyroid follicles perform several functions that depend upon epithelial polarity: secretion of thyroglobulin (Tg) to the apical lumen, uptake of iodide for Tg iodination, and the manufacture of thyroid hormone for delivery to the bloodstream. In this report we examine Tg processing by thyroid epithelial monolayers cultured on porous filters. Basolateral 125I uptake resulted in thyrotropin-depen...

A series of iodine( i ) complexes were prepared and their iodination potential was tested utilising the conversion antipyrine to iodo-antipyrine, results compared, especially with respect ubiquitous Barluenga's reagent.

Radioactive iodine is currently used to label proteins as a method of investigating protein metabolism in vivo or as a tracer for studies in vitro. However, recent observations indicate that changes in the molecular characteristics of proteins after iodination may lead to an apparent increase in the turnover rate in vivo (Regoeczi, 1971 ; Krohn et al., 1972). Incorporation of iodine into protei...

The topographical arrangement of chick synaptosomal plasma membrane polypeptides was examined by lactoperoxidase-catalyzed iodination and trypsin digestion of proteins exposed at the exterior surface. The ““I-labeling profile on sucrose gradients of lysed, subfractionated synaptosomes generally coincided with the activity of the membrane marker (Na+-K+)-activated ATPase, which suggested that la...

Human serum apotransferrin was exposed to the isolated myeloperoxidase-H2O2-halide system or to phorbol ester-activated human neutrophils. Such treatment resulted in a marked loss in transferrin iron binding capacity as well as concomitant iodination of transferrin. Each component of the cell-free system (myeloperoxidase, H2O2, iodide) or neutrophil system (neutrophils, phorbol ester, iodide) w...