<html>

	<head>
		<meta http-equiv="content-type" content="text/html;charset=iso-8859-1">
		<title>Mathews/van Holde/Ahern 3rd Edition</title>
	</head>

	<body bgcolor="#FFFFFF" link="#FF8000" vlink="#FF8000"
alink="#FF8000"<p>
		
		
			
				<font color="#990000" size="5">Affinity Label</font><br>
<img src="../gifs/divider.gif" width="384" height="8"><br>
</p>
			
		
		</h1>
		<p><font >Researchers can learn about the active site of an enzyme (the place on the enzyme where the reaction is catalyzed) by treating the enzyme with a substance that fits into the active site and then covalently binds to it. Such a reaction almost always irreversibly inhibits the enzyme, but leaves a &quot;tag&quot; on the enzyme at the active site. Such &quot;tagging&quot; is called <b>affinity labeling</b> because the molecule must have an <b>affinity</b> for the active site in order to bind there. An <b>affinity labeling</b> compound that is inactive until the enzyme acts on it is called a suicide inhibitor. (see also <a href="ta11p4.htm"><b>Table 11.4</b></a>, <a href="fi11p24.htm"><b>Figure 11.24</b></a><b>.</b></font></p>
		<p><font >
		<hr>
		</font><font ><b>See also: <a href="c11kkkk.htm">K</a></b></font><a href="c11kkkk.htm"><b><font size="1">M</font><font >, k</font><font size="2">CAT</font><font >, and k</font><font size="2">CAT</font><font >/K</font><font size="2">M</font></b></a><font >, <a href="suicidei.htm"><b>Suicide Inhibitor</b></a>, <a href="c11ei.htm"><b>Enzyme Inhibition</b></a>, <a href="c11mmk.htm"><b>Michaelis-Menten Kinetics</b></a>, <a href="c11akd.htm"><b>Analysis of Kinetic Data</b></a></font></p>
		<p><font >
		<hr>
		</font><font color="#990000" ><b>INTERNET LINK: </b></font><b><a href="http://ntri.tamuk.edu/cell/kinetics.html"><font >Enzyme Kinetics</font></a></b></p>
		<p><font ><b>
		<hr>
		</b></font>
	</body>

</html>
