The reactivities of the tyrosyl residues of calf and rabbit cytochrome bs have been examined by acylation, iodination, and titration of the proteins. These experiments distinguish residues 6 and 7 as the most exposed and reactive residues, which ionize normally and can be acetylated or iodinated to form the monoiodo or diiodo derivatives. Tyrosine 30, which is common to both cytochrome preparat...

A large number of iodine atoms can be introduced into a single molecule in a one-pot reaction using trifluoroperacetic acid-mediated electrophilic iodination methodology. The scope of this reaction was investigated extensively using several pyrazole substrates which resulted in nine polyiodo pyrazole compounds with iodine content as high as 80%. This synthetic methodology was also utilized succ...

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...