This old version of Proteopedia is provided for student assignments while the new version is undergoing repairs. Content and edits done in this old version of Proteopedia after March 1, 2026 will eventually be lost when it is retired in about June of 2026.
Apply for new accounts at the new Proteopedia. Your logins will work in both the old and new versions.
1dr8
From Proteopedia
(New page: 200px<br /><applet load="1dr8" size="450" color="white" frame="true" align="right" spinBox="true" caption="1dr8, resolution 2.70Å" /> '''STRUCTURE OF MODIFIE...) |
|||
| Line 1: | Line 1: | ||
| - | [[Image:1dr8.jpg|left|200px]]<br /><applet load="1dr8" size=" | + | [[Image:1dr8.jpg|left|200px]]<br /><applet load="1dr8" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1dr8, resolution 2.70Å" /> | caption="1dr8, resolution 2.70Å" /> | ||
'''STRUCTURE OF MODIFIED 3-ISOPROPYLMALATE DEHYDROGENASE AT THE C-TERMINUS, HD177'''<br /> | '''STRUCTURE OF MODIFIED 3-ISOPROPYLMALATE DEHYDROGENASE AT THE C-TERMINUS, HD177'''<br /> | ||
==Overview== | ==Overview== | ||
| - | Thermal stability of the Thermus thermophilus isopropylmalate | + | Thermal stability of the Thermus thermophilus isopropylmalate dehydrogenase enzyme was substantially lost upon the deletion of three residues from the C-terminus. However, the stability was partly recovered by the addition of two, four and seven amino acid residues (called HD177, HD708 and HD711, respectively) to the C-terminal region of the truncated enzyme. Three structures of these mutant enzymes were determined by an X-ray diffraction method. All protein crystals belong to space group P2(1) and their structures were solved by a standard molecular replacement method where the original dimer structure of the A172L mutant was used as a search model. Thermal stability of these mutant enzymes is discussed based on the 3D structure with special attention to the width of the active-site groove and the minor groove, distortion of beta-sheet pillar structure and size of cavity in the domain-domain interface around the C-terminus. Our previous studies revealed that the thermal stability of isopropylmalate dehydrogenase increases when the active-site cleft is closed (the closed form). In the present study it is shown that the active-site cleft can be regulated by open-close movement of the minor groove located at the opposite side to the active-site groove on the same subunit, through a paperclip-like motion. |
==About this Structure== | ==About this Structure== | ||
| - | 1DR8 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Thermus_thermophilus Thermus thermophilus]. Active as [http://en.wikipedia.org/wiki/3-isopropylmalate_dehydrogenase 3-isopropylmalate dehydrogenase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=1.1.1.85 1.1.1.85] Full crystallographic information is available from [http:// | + | 1DR8 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Thermus_thermophilus Thermus thermophilus]. Active as [http://en.wikipedia.org/wiki/3-isopropylmalate_dehydrogenase 3-isopropylmalate dehydrogenase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=1.1.1.85 1.1.1.85] Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1DR8 OCA]. |
==Reference== | ==Reference== | ||
| Line 23: | Line 23: | ||
[[Category: paperclip motion]] | [[Category: paperclip motion]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 12:19:38 2008'' |
Revision as of 10:19, 21 February 2008
|
STRUCTURE OF MODIFIED 3-ISOPROPYLMALATE DEHYDROGENASE AT THE C-TERMINUS, HD177
Overview
Thermal stability of the Thermus thermophilus isopropylmalate dehydrogenase enzyme was substantially lost upon the deletion of three residues from the C-terminus. However, the stability was partly recovered by the addition of two, four and seven amino acid residues (called HD177, HD708 and HD711, respectively) to the C-terminal region of the truncated enzyme. Three structures of these mutant enzymes were determined by an X-ray diffraction method. All protein crystals belong to space group P2(1) and their structures were solved by a standard molecular replacement method where the original dimer structure of the A172L mutant was used as a search model. Thermal stability of these mutant enzymes is discussed based on the 3D structure with special attention to the width of the active-site groove and the minor groove, distortion of beta-sheet pillar structure and size of cavity in the domain-domain interface around the C-terminus. Our previous studies revealed that the thermal stability of isopropylmalate dehydrogenase increases when the active-site cleft is closed (the closed form). In the present study it is shown that the active-site cleft can be regulated by open-close movement of the minor groove located at the opposite side to the active-site groove on the same subunit, through a paperclip-like motion.
About this Structure
1DR8 is a Single protein structure of sequence from Thermus thermophilus. Active as 3-isopropylmalate dehydrogenase, with EC number 1.1.1.85 Full crystallographic information is available from OCA.
Reference
Crystal structures of 3-isopropylmalate dehydrogenases with mutations at the C-terminus: crystallographic analyses of structure-stability relationships., Nurachman Z, Akanuma S, Sato T, Oshima T, Tanaka N, Protein Eng. 2000 Apr;13(4):253-8. PMID:10810156
Page seeded by OCA on Thu Feb 21 12:19:38 2008
