1n9k: Difference between revisions

[[Image:1n9k.jpg|left|200px]]<br /><applet load="1n9k" size="350" color="white" frame="true" align="right" spinBox="true"  

AphA is a periplasmic acid phosphatase of Escherichia coli belonging to class B bacterial phosphatases, which is part of the DDDD superfamily of phosphohydrolases. The crystal structure of AphA has been determined at 2.2A and its resolution extended to 1.7A on an AuCl(3) derivative. This represents the first crystal structure of a class B bacterial phosphatase. Despite the lack of sequence homology, the AphA structure reveals a haloacid dehalogenase-like fold. This finding suggests that this fold could be conserved among members of the DDDD superfamily of phosphohydrolases. The active enzyme is a homotetramer built by using an extended N-terminal arm intertwining the four monomers. The active site of the native enzyme, as prepared, hosts a magnesium ion, which can be replaced by other metal ions. The structure explains the non-specific behaviour of AphA towards substrates, while a structure-based alignment with other phosphatases provides clues about the catalytic mechanism.

1N9K is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli] with <scene name='pdbligand=MG:'>MG</scene> and <scene name='pdbligand=BR:'>BR</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Acid_phosphatase Acid phosphatase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.1.3.2 3.1.3.2] Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1N9K OCA].  

[[Category: Rossolini, G M.]]

[[Category: Thaller, M C.]]

''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 14:03:45 2008''