|
|
| Line 1: |
Line 1: |
| [[Image:1b5d.gif|left|200px]] | | {{Seed}} |
| | [[Image:1b5d.png|left|200px]] |
|
| |
|
| <!-- | | <!-- |
| Line 9: |
Line 10: |
| {{STRUCTURE_1b5d| PDB=1b5d | SCENE= }} | | {{STRUCTURE_1b5d| PDB=1b5d | SCENE= }} |
|
| |
|
| '''DCMP Hydroxymethylase from T4 (Intact)'''
| | ===DCMP Hydroxymethylase from T4 (Intact)=== |
|
| |
|
|
| |
|
| ==Overview==
| | <!-- |
| Bacteriophage T4 deoxycytidylate hydroxymethylase (EC 2.1.2.8), a homodimer of 246-residue subunits, catalyzes hydroxymethylation of the cytosine base in deoxycytidylate (dCMP) to produce 5-hydroxymethyl-dCMP. It forms part of a phage DNA protection system and appears to function in vivo as a component of a multienzyme complex called deoxyribonucleoside triphosphate (dNTP) synthetase. We have determined its crystal structure in the presence of the substrate dCMP at 1.6 A resolution. The structure reveals a subunit fold and a dimerization pattern in common with thymidylate synthases, despite low (approximately 20%) sequence identity. Among the residues that form the dCMP binding site, those interacting with the sugar and phosphate are arranged in a configuration similar to the deoxyuridylate binding site of thymidylate synthases. However, the residues interacting directly or indirectly with the cytosine base show a more divergent structure and the presumed folate cofactor binding site is more open. Our structure reveals a water molecule properly positioned near C-6 of cytosine to add to the C-7 methylene intermediate during the last step of hydroxymethylation. On the basis of sequence comparison and crystal packing analysis, a hypothetical model for the interaction between T4 deoxycytidylate hydroxymethylase and T4 thymidylate synthase in the dNTP-synthesizing complex has been built.
| | The line below this paragraph, {{ABSTRACT_PUBMED_10064578}}, adds the Publication Abstract to the page |
| | (as it appears on PubMed at http://www.pubmed.gov), where 10064578 is the PubMed ID number. |
| | --> |
| | {{ABSTRACT_PUBMED_10064578}} |
|
| |
|
| ==About this Structure== | | ==About this Structure== |
| Line 28: |
Line 32: |
| [[Category: Dntp synthesizing complex]] | | [[Category: Dntp synthesizing complex]] |
| [[Category: Hydroxymethylase]] | | [[Category: Hydroxymethylase]] |
| ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Fri May 2 11:05:33 2008'' | | |
| | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Mon Jun 30 18:18:14 2008'' |
