1tti
From Proteopedia
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- | [[Image:1tti.gif|left|200px]] | + | [[Image:1tti.gif|left|200px]] |
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- | '''THREE NEW CRYSTAL STRUCTURES OF POINT MUTATION VARIANTS OF MONOTIM: CONFORMATIONAL FLEXIBILITY OF LOOP-1,LOOP-4 AND LOOP-8''' | + | {{Structure |
+ | |PDB= 1tti |SIZE=350|CAPTION= <scene name='initialview01'>1tti</scene>, resolution 2.4Å | ||
+ | |SITE= | ||
+ | |LIGAND= <scene name='pdbligand=PGA:2-PHOSPHOGLYCOLIC ACID'>PGA</scene> | ||
+ | |ACTIVITY= [http://en.wikipedia.org/wiki/Triose-phosphate_isomerase Triose-phosphate isomerase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=5.3.1.1 5.3.1.1] | ||
+ | |GENE= | ||
+ | }} | ||
+ | |||
+ | '''THREE NEW CRYSTAL STRUCTURES OF POINT MUTATION VARIANTS OF MONOTIM: CONFORMATIONAL FLEXIBILITY OF LOOP-1,LOOP-4 AND LOOP-8''' | ||
+ | |||
==Overview== | ==Overview== | ||
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==About this Structure== | ==About this Structure== | ||
- | 1TTI is a [ | + | 1TTI is a [[Single protein]] structure of sequence from [http://en.wikipedia.org/wiki/Trypanosoma_brucei_brucei Trypanosoma brucei brucei]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1TTI OCA]. |
==Reference== | ==Reference== | ||
- | Three new crystal structures of point mutation variants of monoTIM: conformational flexibility of loop-1, loop-4 and loop-8., Borchert TV, Kishan KV, Zeelen JP, Schliebs W, Thanki N, Abagyan R, Jaenicke R, Wierenga RK, Structure. 1995 Jul 15;3(7):669-79. PMID:[http:// | + | Three new crystal structures of point mutation variants of monoTIM: conformational flexibility of loop-1, loop-4 and loop-8., Borchert TV, Kishan KV, Zeelen JP, Schliebs W, Thanki N, Abagyan R, Jaenicke R, Wierenga RK, Structure. 1995 Jul 15;3(7):669-79. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/8591044 8591044] |
[[Category: Single protein]] | [[Category: Single protein]] | ||
[[Category: Triose-phosphate isomerase]] | [[Category: Triose-phosphate isomerase]] | ||
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[[Category: isomerase(intramolecular oxidoreductase)]] | [[Category: isomerase(intramolecular oxidoreductase)]] | ||
- | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Mar 20 14:22:56 2008'' |
Revision as of 12:22, 20 March 2008
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, resolution 2.4Å | |||||||
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Ligands: | |||||||
Activity: | Triose-phosphate isomerase, with EC number 5.3.1.1 | ||||||
Coordinates: | save as pdb, mmCIF, xml |
THREE NEW CRYSTAL STRUCTURES OF POINT MUTATION VARIANTS OF MONOTIM: CONFORMATIONAL FLEXIBILITY OF LOOP-1,LOOP-4 AND LOOP-8
Overview
BACKGROUND: Wild-type triosephosphate isomerase (TIM) is a very stable dimeric enzyme. This dimer can be converted into a stable monomeric protein (monoTIM) by replacing the 15-residue interface loop (loop-3) by a shorter, 8-residue, loop. The crystal structure of monoTIM shows that two active-site loops (loop-1 and loop-4), which are at the dimer interface in wild-type TIM, have acquired rather different structural properties. Nevertheless, monoTIM has residual catalytic activity. RESULTS: Three new structures of variants of monoTIM are presented, a double-point mutant crystallized in the presence and absence of bound inhibitor, and a single-point mutant in the presence of a different inhibitor. These new structures show large structural variability for the active-site loops, loop-1, loop-4 and loop-8. In the structures with inhibitor bound, the catalytic lysine (Lys13 in loop-1) and the catalytic histidine (His95 in loop-4) adopt conformations similar to those observed in wild-type TIM, but very different from the monoTIM structure. CONCLUSIONS: The residual catalytic activity of monoTIM can now be rationalized. In the presence of substrate analogues the active-site loops, loop-1, loop-4 and loop-8, as well as the catalytic residues, adopt conformations similar to those seen in the wild-type protein. These loops lack conformational flexibility in wild-type TIM. The data suggest that the rigidity of these loops in wild-type TIM, resulting from subunit-subunit contacts at the dimer interface, is important for optimal catalysis.
About this Structure
1TTI is a Single protein structure of sequence from Trypanosoma brucei brucei. Full crystallographic information is available from OCA.
Reference
Three new crystal structures of point mutation variants of monoTIM: conformational flexibility of loop-1, loop-4 and loop-8., Borchert TV, Kishan KV, Zeelen JP, Schliebs W, Thanki N, Abagyan R, Jaenicke R, Wierenga RK, Structure. 1995 Jul 15;3(7):669-79. PMID:8591044
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