1aj0: Difference between revisions

New page: left|200px<br /><applet load="1aj0" size="450" color="white" frame="true" align="right" spinBox="true" caption="1aj0, resolution 2.0Å" /> '''CRYSTAL STRUCTURE OF ...
 
No edit summary
Line 1: Line 1:
[[Image:1aj0.gif|left|200px]]<br /><applet load="1aj0" size="450" color="white" frame="true" align="right" spinBox="true"  
[[Image:1aj0.gif|left|200px]]<br /><applet load="1aj0" size="350" color="white" frame="true" align="right" spinBox="true"  
caption="1aj0, resolution 2.0&Aring;" />
caption="1aj0, resolution 2.0&Aring;" />
'''CRYSTAL STRUCTURE OF A TERNARY COMPLEX OF E. COLI DIHYDROPTEROATE SYNTHASE'''<br />
'''CRYSTAL STRUCTURE OF A TERNARY COMPLEX OF E. COLI DIHYDROPTEROATE SYNTHASE'''<br />


==Overview==
==Overview==
Sulfonamides were amongst the first clinically useful antibacterial agents, to be discovered. The identification of sulfanilamide as the active, component of the dye Prontosil rubrum led to the synthesis of clinically, useful analogues. Today sulfamethoxazole (in combination with, trimethoprim), is used to treat urinary tract infections caused by, bacteria such as Escherichia coli and is also a first-line treatment for, pneumonia caused by the fungus Pneumocystis carinii, a common condition in, AIDS patients. The site of action is the de novo folate biosynthesis, enzyme dihydropteroate synthase (DHPS) where sulfonamides act as analogues, of one of the substrates, para-aminobenzoic acid (pABA). We report here, the crystal structure of E.coli DHPS at 2.0 A resolution refined to an, R-factor of 0.185. The single domain of 282 residues forms an, eight-stranded alpha/beta-barrel. The 7,8-dihydropterin pyrophosphate, (DHPPP) substrate binds in a deep cleft in the barrel, whilst, sulfanilamide binds closer to the surface. The DHPPP ligand site is highly, conserved amongst prokaryotic and eukaryotic DHPSs.
Sulfonamides were amongst the first clinically useful antibacterial agents to be discovered. The identification of sulfanilamide as the active component of the dye Prontosil rubrum led to the synthesis of clinically useful analogues. Today sulfamethoxazole (in combination with trimethoprim), is used to treat urinary tract infections caused by bacteria such as Escherichia coli and is also a first-line treatment for pneumonia caused by the fungus Pneumocystis carinii, a common condition in AIDS patients. The site of action is the de novo folate biosynthesis enzyme dihydropteroate synthase (DHPS) where sulfonamides act as analogues of one of the substrates, para-aminobenzoic acid (pABA). We report here the crystal structure of E.coli DHPS at 2.0 A resolution refined to an R-factor of 0.185. The single domain of 282 residues forms an eight-stranded alpha/beta-barrel. The 7,8-dihydropterin pyrophosphate (DHPPP) substrate binds in a deep cleft in the barrel, whilst sulfanilamide binds closer to the surface. The DHPPP ligand site is highly conserved amongst prokaryotic and eukaryotic DHPSs.


==About this Structure==
==About this Structure==
1AJ0 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 SO4, PH2 and SAN as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Dihydropteroate_synthase Dihydropteroate synthase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.5.1.15 2.5.1.15] Full crystallographic information is available from [http://ispc.weizmann.ac.il/oca-bin/ocashort?id=1AJ0 OCA].  
1AJ0 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=SO4:'>SO4</scene>, <scene name='pdbligand=PH2:'>PH2</scene> and <scene name='pdbligand=SAN:'>SAN</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Dihydropteroate_synthase Dihydropteroate synthase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.5.1.15 2.5.1.15] Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1AJ0 OCA].  


==Reference==
==Reference==
Line 15: Line 15:
[[Category: Single protein]]
[[Category: Single protein]]
[[Category: Achari, A.]]
[[Category: Achari, A.]]
[[Category: Bryant, P.K.]]
[[Category: Bryant, P K.]]
[[Category: Champness, J.N.]]
[[Category: Champness, J N.]]
[[Category: Rosemond, J.]]
[[Category: Rosemond, J.]]
[[Category: Somers, D.O.]]
[[Category: Somers, D O.]]
[[Category: Stammers, D.K.]]
[[Category: Stammers, D K.]]
[[Category: PH2]]
[[Category: PH2]]
[[Category: SAN]]
[[Category: SAN]]
Line 30: Line 30:
[[Category: transferase]]
[[Category: transferase]]


''Page seeded by [http://ispc.weizmann.ac.il/oca OCA ] on Tue Nov 20 10:53:36 2007''
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 11:45:05 2008''

Proteopedia Page Contributors and Editors (what is this?)Proteopedia Page Contributors and Editors (what is this?)

OCA