2ayq
From Proteopedia
(New page: 200px<br /><applet load="2ayq" size="450" color="white" frame="true" align="right" spinBox="true" caption="2ayq, resolution 3.0Å" /> '''3-ISOPROPYLMALATE DEH...) |
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- | [[Image:2ayq.jpg|left|200px]]<br /><applet load="2ayq" size=" | + | [[Image:2ayq.jpg|left|200px]]<br /><applet load="2ayq" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="2ayq, resolution 3.0Å" /> | caption="2ayq, resolution 3.0Å" /> | ||
'''3-ISOPROPYLMALATE DEHYDROGENASE FROM THE MODERATE FACULTATIVE THERMOPHILE, BACILLUS COAGULANS'''<br /> | '''3-ISOPROPYLMALATE DEHYDROGENASE FROM THE MODERATE FACULTATIVE THERMOPHILE, BACILLUS COAGULANS'''<br /> | ||
==Overview== | ==Overview== | ||
- | The crystal structure of 3-isopropylmalate dehydrogenase from the moderate | + | The crystal structure of 3-isopropylmalate dehydrogenase from the moderate facultative thermophile Bacillus coagulans (BcIPMDH) has been determined by the X-ray method. BcIPMDH is a dimeric enzyme composed of two identical subunits, each of which takes an open alpha/beta structure with 11 alpha-helices and 14 beta-strands. The polypeptide is folded into two domains. The first domain is composed of residues 1-101 and 257-356, and the second domain, of residues 102-256. The latter domains of the two subunits are associated with one another by a dyad axis to make the dimer, locally forming a beta-sheet and a four-helix bundle. As compared with the structure of the enzyme from the extreme thermophile Thermus thermophilus (TtIPMDH), a new short beta-sheet (residues 329-330 and 340-341) absent in TtIPMDH is formed by the insertion of 5 residues in BcIPMDH. In terms of determinants for thermostabilization, both consistent and inconsistent changes were found between the two enzymes. The regions including inconsistent changes are formed by different usages of the determinants for stabilizing the loops at different levels. Those in BcIPMDH contain some structural redundancies in length of amino acid sequence and flexibility of residues, which seem to be unnecessary for the enzymatic reaction. Such redundancies are also found in the primary structure of the enzyme of the mesophile Bacillus subtilis, but these parts are more stabilized in BcIPMDH by hydrogen bonds and salt bridges. On the other hand, TtIPMDH is stabilized by reducing such redundant parts. This contrast suggests that different strategies may be preferred for thermostabilization, depending on temperature. |
==About this Structure== | ==About this Structure== | ||
- | 2AYQ is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Bacillus_coagulans Bacillus coagulans]. This structure | + | 2AYQ is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Bacillus_coagulans Bacillus coagulans]. This structure supersedes the now removed PDB entry 1AYQ. 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=2AYQ OCA]. |
==Reference== | ==Reference== | ||
- | Crystal structure of 3-isopropylmalate dehydrogenase from the moderate facultative thermophile, Bacillus coagulans: two strategies for thermostabilization of protein structures., Tsuchiya D, Sekiguchi T, Takenaka A, J Biochem | + | Crystal structure of 3-isopropylmalate dehydrogenase from the moderate facultative thermophile, Bacillus coagulans: two strategies for thermostabilization of protein structures., Tsuchiya D, Sekiguchi T, Takenaka A, J Biochem. 1997 Dec;122(6):1092-104. PMID:[http://ispc.weizmann.ac.il//pmbin/getpm?pmid=9498551 9498551] |
[[Category: 3-isopropylmalate dehydrogenase]] | [[Category: 3-isopropylmalate dehydrogenase]] | ||
[[Category: Bacillus coagulans]] | [[Category: Bacillus coagulans]] | ||
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[[Category: Takenaka, A.]] | [[Category: Takenaka, A.]] | ||
[[Category: Tsuchiya, D.]] | [[Category: Tsuchiya, D.]] | ||
- | [[Category: 3-isopropylmalate dehydrogenase]] | ||
[[Category: leucine biosynthesis]] | [[Category: leucine biosynthesis]] | ||
[[Category: moderate thermophile]] | [[Category: moderate thermophile]] | ||
[[Category: oxidoreductase]] | [[Category: oxidoreductase]] | ||
- | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 16:32:24 2008'' |
Revision as of 14:32, 21 February 2008
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3-ISOPROPYLMALATE DEHYDROGENASE FROM THE MODERATE FACULTATIVE THERMOPHILE, BACILLUS COAGULANS
Overview
The crystal structure of 3-isopropylmalate dehydrogenase from the moderate facultative thermophile Bacillus coagulans (BcIPMDH) has been determined by the X-ray method. BcIPMDH is a dimeric enzyme composed of two identical subunits, each of which takes an open alpha/beta structure with 11 alpha-helices and 14 beta-strands. The polypeptide is folded into two domains. The first domain is composed of residues 1-101 and 257-356, and the second domain, of residues 102-256. The latter domains of the two subunits are associated with one another by a dyad axis to make the dimer, locally forming a beta-sheet and a four-helix bundle. As compared with the structure of the enzyme from the extreme thermophile Thermus thermophilus (TtIPMDH), a new short beta-sheet (residues 329-330 and 340-341) absent in TtIPMDH is formed by the insertion of 5 residues in BcIPMDH. In terms of determinants for thermostabilization, both consistent and inconsistent changes were found between the two enzymes. The regions including inconsistent changes are formed by different usages of the determinants for stabilizing the loops at different levels. Those in BcIPMDH contain some structural redundancies in length of amino acid sequence and flexibility of residues, which seem to be unnecessary for the enzymatic reaction. Such redundancies are also found in the primary structure of the enzyme of the mesophile Bacillus subtilis, but these parts are more stabilized in BcIPMDH by hydrogen bonds and salt bridges. On the other hand, TtIPMDH is stabilized by reducing such redundant parts. This contrast suggests that different strategies may be preferred for thermostabilization, depending on temperature.
About this Structure
2AYQ is a Single protein structure of sequence from Bacillus coagulans. This structure supersedes the now removed PDB entry 1AYQ. Active as 3-isopropylmalate dehydrogenase, with EC number 1.1.1.85 Full crystallographic information is available from OCA.
Reference
Crystal structure of 3-isopropylmalate dehydrogenase from the moderate facultative thermophile, Bacillus coagulans: two strategies for thermostabilization of protein structures., Tsuchiya D, Sekiguchi T, Takenaka A, J Biochem. 1997 Dec;122(6):1092-104. PMID:9498551
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