1. Adenosine deaminase was inactivated by 9-(4-bromoacetamidobenzyl)-adenine (I) and 9-(2-bromoacetamidobenzyl)adenine (II), two affinity labels. 2. The stoichiometry of the reaction with reagent II is reported: 1 mol reagent is bound per mol inactive enzyme. Amino acid analysis of the 6 N HCl hydrolyzate of the inactive enzyme identified CM-histidine as the main alkylation product. This is the first evidence of the presence of a histidine in the active site region. 3. The alkylation rate and involved amino acid residues were studied for both reagents I and II, at pH 8 and 5.5. The particular reactivity of a lysine near or in the active site is discussed.
|Autori:||LUCACCHINI A; BERTOLINI AD; RONCA G; SEGNINI D; ROSSI CA|
|Titolo:||AFFINITY LABELING OF HISTIDINE AND LYSINE RESIDUES IN THE ADENOSINE-DEAMINASE SUBSTRATE BINDING-SITE|
|Anno del prodotto:||1979|
|Digital Object Identifier (DOI):||10.1016/0005-2744(79)90057-3|
|Appare nelle tipologie:||1.1 Articolo in rivista|