| Autor: |
Lin CM; Department of Biochemistry, University of Nebraska, Lincoln 68583-0718., Mihal KA, Krueger RJ |
| Jazyk: |
angličtina |
| Zdroj: |
Analytical biochemistry [Anal Biochem] 1989 Jun; Vol. 179 (2), pp. 389-95. |
| DOI: |
10.1016/0003-2697(89)90150-4 |
| Abstrakt: |
Preparation and use of N-iodoacetyltyramine in generation of 125I-labeled compounds is described. The kinetics of alkylation of N-acetylcysteine by N-iodoacetyltyramine (k2 = 3.0 M-1 s-1) and N-chloroacetyltyramine (k2 = 0.12 M-1 s-1) indicate that N-iodoacetyltyramine is more useful for labeling sulfhydryl-containing compounds to high specific activity with 125I. Conditions for preparation of carrier-free 125I-labeled N-iodoacetyl-3-monoiodotyramine in 50% yield based on starting iodide are described. The high degree of group specificity of N-iodoacetyl-3-monoiodotyramine reaction with sulfhydryl groups is demonstrated by the high reactivity toward sulfhydryl-containing bovine serum albumin and low reactivity toward N-ethylmaleimide-blocked bovine serum albumin and IgG. 125I-labeled N-iodoacetyl-3-monoiodotyramine was also used to prepare an 125I-labeled ACTH derivative that retains full biological activity, further demonstrating the selectivity toward reactions with sulfhydryl groups. |
| Databáze: |
MEDLINE |
| Externí odkaz: |
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