Surface-exposed proteins of vinblastine-sensitive human lymphoid cell line of leukemic origin (CCRF-CEM) were examined by the lactoperoxidase-catalyzed iodination and two-dimensional polyacrylamide gel electrophoresis methods. Spots which comigrate with bovine brain tubulin and rabbit muscle actin were prominently labeled in the whole membrane but not in the high-speed supernatant fraction of t...

In the course of a study of the thermodynamics of the ionization of the lysyl residue of insulin (l), it was found desirable to make an iodinated derivative of insulin in order to convert the four tyrosyl residues in the monomer (molecular weight 5733 (2)) to 3,5-diiodotyrosyl groups which have lower pK values (3). Numerous properties of the iodinated derivative have been studied in order to as...

A new rapid iodination reagent, N1,N3,N5-tris[(2,4,6-trimethylpyridine)iodo(I)]-2,4,6-triphenyl-s-triazine trihexafluorophosphate, was synthesized in a modification of the established synthesis 2,4,6-triiodo-3,5-dimethylphenol presence bis(2,4,6-trimethylpyridine)iodo(I) hexafluorophosphate and used for precise post-modification mono- trisubstituted phenyl compounds. We performed triple iodinat...

The results of metabolic labeling studies and enzymatic treatments followed by analysis on polyacrylamide gels show that the external proteins of hamster fibroblast cell lines, which have been identified by lactoperoxidase-catalyzed iodination, do not contain sulphated mucopolysaccharides or hyaluronic acid and are probably unrelated to collagen. Several of the iodinated species comigrate with ...

Measurements of neck count-rates for personnel who regularly iodinated proteins with 125I showed that, generally, count rates were higher after iodination than before. The major pathway for the intake of 125I during iodination was through skin that was exposed to the free-iodine atmosphere of the fume hood. Neck count-rates were measured in 34 other subjects who were working with 125I. The rate...

Utilizing cell preparations that contained greater than 90% eosinophils and sodium azide to inhibit the lysosomal enzyme peroxidase, studies of eosinophil bactericidal activity were undertaken. Eosinophils did not kill bacteria as well as neutrophils, principally because of a reduced phagocytic capacity. In contrast to neutrophils, eosinophils had high resting iodination activity but failed to ...