7icd: Difference between revisions
New page: left|200px<br /><applet load="7icd" size="450" color="white" frame="true" align="right" spinBox="true" caption="7icd, resolution 2.4Å" /> '''REGULATION OF AN ENZY... |
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[[Image:7icd.gif|left|200px]]<br /><applet load="7icd" size=" | [[Image:7icd.gif|left|200px]]<br /><applet load="7icd" size="350" color="white" frame="true" align="right" spinBox="true" | ||
caption="7icd, resolution 2.4Å" /> | caption="7icd, resolution 2.4Å" /> | ||
'''REGULATION OF AN ENZYME BY PHOSPHORYLATION AT THE ACTIVE SITE'''<br /> | '''REGULATION OF AN ENZYME BY PHOSPHORYLATION AT THE ACTIVE SITE'''<br /> | ||
==Overview== | ==Overview== | ||
The isocitrate dehydrogenase of Escherichia coli is an example of a | The isocitrate dehydrogenase of Escherichia coli is an example of a ubiquitous class of enzymes that are regulated by covalent modification. In the three-dimensional structure of the enzyme-substrate complex, isocitrate forms a hydrogen bond with Ser113, the site of regulatory phosphorylation. The structures of Asp113 and Glu113 mutants, which mimic the inactivation of the enzyme by phosphorylation, show minimal conformational changes from wild type, as in the phosphorylated enzyme. Calculations based on observed structures suggest that the change in electrostatic potential when a negative charge is introduced either by phosporylation or site-directed mutagenesis is sufficient to inactivate the enzyme. Thus, direct interaction at a ligand binding site is an alternative mechanism to induced conformational changes from an allosteric site in the regulation of protein activity by phosphorylation. | ||
==About this Structure== | ==About this Structure== | ||
7ICD is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli]. Active as [http://en.wikipedia.org/wiki/Isocitrate_dehydrogenase_(NADP(+)) Isocitrate dehydrogenase (NADP(+))], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=1.1.1.42 1.1.1.42] Full crystallographic information is available from [http:// | 7ICD is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli]. Active as [http://en.wikipedia.org/wiki/Isocitrate_dehydrogenase_(NADP(+)) Isocitrate dehydrogenase (NADP(+))], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=1.1.1.42 1.1.1.42] Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=7ICD OCA]. | ||
==Reference== | ==Reference== | ||
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[[Category: Isocitrate dehydrogenase (NADP(+))]] | [[Category: Isocitrate dehydrogenase (NADP(+))]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
[[Category: Dean, A | [[Category: Dean, A M.]] | ||
[[Category: Hurley, J | [[Category: Hurley, J H.]] | ||
[[Category: Koshlandjunior, D | [[Category: Koshlandjunior, D E.]] | ||
[[Category: Sohl, J | [[Category: Sohl, J L.]] | ||
[[Category: Stroud, R | [[Category: Stroud, R M.]] | ||
[[Category: oxidoreductase (nad(a)-choh(d))]] | [[Category: oxidoreductase (nad(a)-choh(d))]] | ||
''Page seeded by [http:// | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 19:17:13 2008'' | ||
