1b02: Difference between revisions
New page: left|200px<br /><applet load="1b02" size="450" color="white" frame="true" align="right" spinBox="true" caption="1b02, resolution 2.5Å" /> '''CRYSTAL STRUCTURE OF ... |
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[[Image:1b02.gif|left|200px]]<br /><applet load="1b02" size=" | [[Image:1b02.gif|left|200px]]<br /><applet load="1b02" size="350" color="white" frame="true" align="right" spinBox="true" | ||
caption="1b02, resolution 2.5Å" /> | caption="1b02, resolution 2.5Å" /> | ||
'''CRYSTAL STRUCTURE OF THYMIDYLATE SYNTHASE A FROM BACILLUS SUBTILIS'''<br /> | '''CRYSTAL STRUCTURE OF THYMIDYLATE SYNTHASE A FROM BACILLUS SUBTILIS'''<br /> | ||
==Overview== | ==Overview== | ||
Thymidylate synthase (TS) converts dUMP to dTMP by reductive methylation, where 5,10-methylenetetrahydrofolate is the source of both the methylene | Thymidylate synthase (TS) converts dUMP to dTMP by reductive methylation, where 5,10-methylenetetrahydrofolate is the source of both the methylene group and reducing equivalents. The mechanism of this reaction has been extensively studied, mainly using the enzyme from Escherichia coli. Bacillus subtilis contains two genes for TSs, ThyA and ThyB. The ThyB enzyme is very similar to other bacterial TSs, but the ThyA enzyme is quite different, both in sequence and activity. In ThyA TS, the active site histidine is replaced by valine. In addition, the B. subtilis enzyme has a 2.4-fold greater k(cat) than the E. coli enzyme. The structure of B. subtilis thymidylate synthase in a ternary complex with 5-fluoro-dUMP and 5,10-methylenetetrahydrofolate has been determined to 2.5 A resolution. Overall, the structure of B. subtilis TS (ThyA) is similar to that of the E. coli enzyme. However, there are significant differences in the structures of two loops, the dimer interface and the details of the active site. The effects of the replacement of histidine by valine and a serine to glutamine substitution in the active site area, and the addition of a loop over the carboxy terminus may account for the differences in k(cat) found between the two enzymes. | ||
==About this Structure== | ==About this Structure== | ||
1B02 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Bacillus_subtilis Bacillus subtilis] with UFP and C2F as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [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] Full crystallographic information is available from [http:// | 1B02 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Bacillus_subtilis Bacillus subtilis] with <scene name='pdbligand=UFP:'>UFP</scene> and <scene name='pdbligand=C2F:'>C2F</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [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] Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1B02 OCA]. | ||
==Reference== | ==Reference== | ||
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[[Category: Thymidylate synthase]] | [[Category: Thymidylate synthase]] | ||
[[Category: Changchien, L.]] | [[Category: Changchien, L.]] | ||
[[Category: Fox, K | [[Category: Fox, K M.]] | ||
[[Category: Garibian, A.]] | [[Category: Garibian, A.]] | ||
[[Category: Maley, F.]] | [[Category: Maley, F.]] | ||
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[[Category: transferase]] | [[Category: transferase]] | ||
''Page seeded by [http:// | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 11:50:08 2008'' | ||
Revision as of 12:50, 21 February 2008
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CRYSTAL STRUCTURE OF THYMIDYLATE SYNTHASE A FROM BACILLUS SUBTILIS
OverviewOverview
Thymidylate synthase (TS) converts dUMP to dTMP by reductive methylation, where 5,10-methylenetetrahydrofolate is the source of both the methylene group and reducing equivalents. The mechanism of this reaction has been extensively studied, mainly using the enzyme from Escherichia coli. Bacillus subtilis contains two genes for TSs, ThyA and ThyB. The ThyB enzyme is very similar to other bacterial TSs, but the ThyA enzyme is quite different, both in sequence and activity. In ThyA TS, the active site histidine is replaced by valine. In addition, the B. subtilis enzyme has a 2.4-fold greater k(cat) than the E. coli enzyme. The structure of B. subtilis thymidylate synthase in a ternary complex with 5-fluoro-dUMP and 5,10-methylenetetrahydrofolate has been determined to 2.5 A resolution. Overall, the structure of B. subtilis TS (ThyA) is similar to that of the E. coli enzyme. However, there are significant differences in the structures of two loops, the dimer interface and the details of the active site. The effects of the replacement of histidine by valine and a serine to glutamine substitution in the active site area, and the addition of a loop over the carboxy terminus may account for the differences in k(cat) found between the two enzymes.
About this StructureAbout this Structure
1B02 is a Single protein structure of sequence from Bacillus subtilis with and as ligands. Active as Thymidylate synthase, with EC number 2.1.1.45 Full crystallographic information is available from OCA.
ReferenceReference
Crystal structure of thymidylate synthase A from Bacillus subtilis., Fox KM, Maley F, Garibian A, Changchien LM, Van Roey P, Protein Sci. 1999 Mar;8(3):538-44. PMID:10091656
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