Radical directed dissociation for facile identification of iodotyrosine residues using electrospray ionization mass spectrometry.

ABSTRACT: Iodination of tyrosine residues in proteins has many uses in chemistry, biology, and medicine. Site specific identification of the sites of iodination is important for many of these uses. Reported herein is a facile method employing photodissociation and mass spectrometry to localize sites of iodination in whole proteins. Absorption of ultraviolet photons by iodotyrosine results in loss of iodine via homolytic bond dissociation. The resulting protein radical fragments in the vicinity of the iodotyrosine upon collisional activation. Analysis of the fragments within the vicinity of each tyrosine residue in the protein enables quantitative evaluation of the likelihood for iodination at each site. The results are compared with both traditional bottom up and top down mass spectrometric methods.

SUBMITTER: Sun Q 

PROVIDER: S-EPMC2878766 | biostudies-literature | 2010 May

REPOSITORIES: biostudies-literature