1ye4: Difference between revisions

[[Image:1ye4.gif|left|200px]]<br /><applet load="1ye4" size="350" color="white" frame="true" align="right" spinBox="true"  

Aldo-keto reductases of family 2 employ single site replacement Lys--&gt;Arg to switch their cosubstrate preference from NADPH to NADH. X-ray crystal structures of Lys-274--&gt;Arg mutant of Candida tenuis xylose reductase (AKR2B5) bound to NAD+ and NADP+ were determined at a resolution of 2.4 and 2.3A, respectively. Due to steric conflicts in the NADP+-bound form, the arginine side chain must rotate away from the position of the original lysine side chain, thereby disrupting a network of direct and water-mediated interactions between Glu-227, Lys-274 and the cofactor 2'-phosphate and 3'-hydroxy groups. Because anchoring contacts of its Glu-227 are lost, the coenzyme-enfolding loop that becomes ordered upon binding of NAD(P)+ in the wild-type remains partly disordered in the NADP+-bound mutant. The results delineate a catalytic reaction profile for the mutant in comparison to wild-type.

1YE4 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Candida_tenuis Candida tenuis] with <scene name='pdbligand=SO4:'>SO4</scene> and <scene name='pdbligand=NAD:'>NAD</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1YE4 OCA].  

[[Category: Wilson, D K.]]

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