1q8f
From Proteopedia
(New page: 200px<br /><applet load="1q8f" size="450" color="white" frame="true" align="right" spinBox="true" caption="1q8f, resolution 1.70Å" /> '''Crystal Structure of...) |
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| - | [[Image:1q8f.gif|left|200px]]<br /><applet load="1q8f" size=" | + | [[Image:1q8f.gif|left|200px]]<br /><applet load="1q8f" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1q8f, resolution 1.70Å" /> | caption="1q8f, resolution 1.70Å" /> | ||
'''Crystal Structure of the E.coli pyrimidine nucleoside hydrolase yeiK'''<br /> | '''Crystal Structure of the E.coli pyrimidine nucleoside hydrolase yeiK'''<br /> | ||
==Overview== | ==Overview== | ||
| - | Enzymes with nucleoside hydrolase (NH) activity are crucial for salvaging | + | Enzymes with nucleoside hydrolase (NH) activity are crucial for salvaging nucleic acid components in purine auxotrophic protozoan parasites, but are also present in prokaryotes and higher eukaryotes. Here we analyze the distribution of genes encoding for putative NH proteins and characterize the yeiK gene product from Escherichia coli as a pyrimidine-specific NH. The crystal structure of YeiK to 1.7 A defines the structural basis for its substrate specificity and identifies residues involved in the catalytic mechanism that differ from both nonspecific and purine-specific NHs. Large differences in the tetrameric quaternary structure compared to nonspecific protozoan NHs are brought forth by minor differences in the interacting surfaces. The first structural and functional characterization of a nonparasitic, pyrimidine nucleoside-specific NH suggests a possible role for these enzymes in the metabolism of tRNA nucleosides. The high catalytic efficiency of YeiK toward 5-fluorouridine could be exploited for suicide gene therapy in cancer treatment. |
==About this Structure== | ==About this Structure== | ||
| - | 1Q8F 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 CA and GOL as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Ribosylpyrimidine_nucleosidase Ribosylpyrimidine nucleosidase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.2.2.8 3.2.2.8] Full crystallographic information is available from [http:// | + | 1Q8F 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=CA:'>CA</scene> and <scene name='pdbligand=GOL:'>GOL</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Ribosylpyrimidine_nucleosidase Ribosylpyrimidine nucleosidase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.2.2.8 3.2.2.8] Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1Q8F OCA]. |
==Reference== | ==Reference== | ||
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[[Category: open alpha-beta structure]] | [[Category: open alpha-beta structure]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 14:36:55 2008'' |
Revision as of 12:36, 21 February 2008
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Crystal Structure of the E.coli pyrimidine nucleoside hydrolase yeiK
Overview
Enzymes with nucleoside hydrolase (NH) activity are crucial for salvaging nucleic acid components in purine auxotrophic protozoan parasites, but are also present in prokaryotes and higher eukaryotes. Here we analyze the distribution of genes encoding for putative NH proteins and characterize the yeiK gene product from Escherichia coli as a pyrimidine-specific NH. The crystal structure of YeiK to 1.7 A defines the structural basis for its substrate specificity and identifies residues involved in the catalytic mechanism that differ from both nonspecific and purine-specific NHs. Large differences in the tetrameric quaternary structure compared to nonspecific protozoan NHs are brought forth by minor differences in the interacting surfaces. The first structural and functional characterization of a nonparasitic, pyrimidine nucleoside-specific NH suggests a possible role for these enzymes in the metabolism of tRNA nucleosides. The high catalytic efficiency of YeiK toward 5-fluorouridine could be exploited for suicide gene therapy in cancer treatment.
About this Structure
1Q8F is a Single protein structure of sequence from Escherichia coli with and as ligands. Active as Ribosylpyrimidine nucleosidase, with EC number 3.2.2.8 Full crystallographic information is available from OCA.
Reference
Crystal structure to 1.7 a of the Escherichia coli pyrimidine nucleoside hydrolase YeiK, a novel candidate for cancer gene therapy., Giabbai B, Degano M, Structure. 2004 May;12(5):739-49. PMID:15130467
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