1njd: Difference between revisions

From Proteopedia
Jump to navigation Jump to search
No edit summary
No edit summary
Line 1: Line 1:
[[Image:1njd.gif|left|200px]]
[[Image:1njd.gif|left|200px]]


{{Structure
<!--
|PDB= 1njd |SIZE=350|CAPTION= <scene name='initialview01'>1njd</scene>, resolution 2.2&Aring;
The line below this paragraph, containing "STRUCTURE_1njd", creates the "Structure Box" on the page.
|SITE= <scene name='pdbsite=CAT:Catalytic+CYS'>CAT</scene>
You may change the PDB parameter (which sets the PDB file loaded into the applet)  
|LIGAND= <scene name='pdbligand=UMP:2&#39;-DEOXYURIDINE+5&#39;-MONOPHOSPHATE'>UMP</scene>
or the SCENE parameter (which sets the initial scene displayed when the page is loaded),
|ACTIVITY= <span class='plainlinks'>[http://en.wikipedia.org/wiki/Thymidylate_synthase Thymidylate synthase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.1.1.45 2.1.1.45] </span>
or leave the SCENE parameter empty for the default display.
|GENE= N229D MUTANT OF CLONED L. CASE ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=1582 Lactobacillus casei])
-->
|DOMAIN=
{{STRUCTURE_1njd|  PDB=1njd |  SCENE= }}  
|RELATEDENTRY=
|RESOURCES=<span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1njd FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1njd OCA], [http://www.ebi.ac.uk/pdbsum/1njd PDBsum], [http://www.rcsb.org/pdb/explore.do?structureId=1njd RCSB]</span>
}}


'''THYMIDYLATE SYNTHASE, MUTATION, N229D WITH 2'-DEOXYURIDINE 5'-MONOPHOSPHATE (DUMP)'''
'''THYMIDYLATE SYNTHASE, MUTATION, N229D WITH 2'-DEOXYURIDINE 5'-MONOPHOSPHATE (DUMP)'''
Line 28: Line 25:
[[Category: Finer-Moore, J.]]
[[Category: Finer-Moore, J.]]
[[Category: Stroud, R M.]]
[[Category: Stroud, R M.]]
[[Category: methyltransferase]]
[[Category: Methyltransferase]]
[[Category: nucleotide biosynthesis]]
[[Category: Nucleotide biosynthesis]]
[[Category: transferase]]
[[Category: Transferase]]
 
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sat May  3 02:36:09 2008''
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sun Mar 30 22:31:11 2008''

Revision as of 02:36, 3 May 2008

File:1njd.gif

Template:STRUCTURE 1njd

THYMIDYLATE SYNTHASE, MUTATION, N229D WITH 2'-DEOXYURIDINE 5'-MONOPHOSPHATE (DUMP)


OverviewOverview

Thymidylate synthase (TS) methylates only dUMP, not dCMP. The crystal structure of TS.dCMP shows sCMP 4-NH2 excluded from the space between Asn-229 and His-199 by the hydrogen bonding and steric properties and Asn-229. Consequently, 6-C of dCMP is over 4 A from the active site sulfhydryl. The Asn-229 side chain is prevented from flipping 180 degrees to and orientation the could hydrogen bond to dCMP by a hydrogen bond network between conserved residues. Thus, the specific binding of dUMP by TS results from occlusion of competing substrates by steric and electronic effects of residues in the active site cavity. When Asn-229 is replaced by a cysteine, the Cys-229 S gamma rotates out of the active site, and the mutant enzyme binds both dCMP and dUMP tightly but does not methylate dCMP. Thus simply admitting dCMP into the dUMP binding site of TS is not sufficient for methylation of dCMP. Structures of nucleotide complexes of TS N229D provide a reasonable explanation for the preferential methylation of dCMP instead of dUMP by this mutant. In TS N229D.dCMP, Asp-229 forms hydrogen bonds to 3-N and 40NH2 of dCMP. Neither the Asp-229 carboxyl moiety nor ordered water appears to hydrogen bond to 4-O of dUMP. Hydrogen bonds to 4-O (or 4-NH2) have been proposed to stabilize reaction intermediates. If their absence in TS N229D.dUMP persists in the ternary complex, it could explain the 10(4)-fold decrease in kcat/Km for dUMP.

About this StructureAbout this Structure

1NJD is a Single protein structure of sequence from Lactobacillus casei. Full crystallographic information is available from OCA.

ReferenceReference

Partitioning roles of side chains in affinity, orientation, and catalysis with structures for mutant complexes: asparagine-229 in thymidylate synthase., Finer-Moore JS, Liu L, Schafmeister CE, Birdsall DL, Mau T, Santi DV, Stroud RM, Biochemistry. 1996 Apr 23;35(16):5125-36. PMID:8611496 Page seeded by OCA on Sat May 3 02:36:09 2008

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

OCA