1TTI

THREE NEW CRYSTAL STRUCTURES OF POINT MUTATION VARIANTS OF MONOTIM: CONFORMATIONAL FLEXIBILITY OF LOOP-1,LOOP-4 AND LOOP-8


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.40 Å
  • R-Value Work: 0.178 

wwPDB Validation   3D Report Full Report


This is version 1.6 of the entry. See complete history


Literature

Three new crystal structures of point mutation variants of monoTIM: conformational flexibility of loop-1, loop-4 and loop-8.

Borchert, T.V.Kishan, K.V.Zeelen, J.P.Schliebs, W.Thanki, N.Abagyan, R.Jaenicke, R.Wierenga, R.K.

(1995) Structure 3: 669-679

  • DOI: https://doi.org/10.1016/s0969-2126(01)00202-7
  • Primary Citation of Related Structures:  
    1MSS, 1TTI, 1TTJ

  • PubMed Abstract: 

    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. 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. 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.


  • Organizational Affiliation

    EMBL, Heidelberg, Germany.


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
TRIOSEPHOSPHATE ISOMERASE243Trypanosoma brucei bruceiMutation(s): 6 
EC: 5.3.1.1
UniProt
Find proteins for P04789 (Trypanosoma brucei brucei)
Explore P04789 
Go to UniProtKB:  P04789
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP04789
Sequence Annotations
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  • Reference Sequence
Small Molecules
Ligands 1 Unique
IDChains Name / Formula / InChI Key2D Diagram3D Interactions
PGA
Query on PGA

Download Ideal Coordinates CCD File 
B [auth A]2-PHOSPHOGLYCOLIC ACID
C2 H5 O6 P
ASCFNMCAHFUBCO-UHFFFAOYSA-N
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.40 Å
  • R-Value Work: 0.178 
  • Space Group: C 1 2 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 78.78α = 90
b = 46.76β = 113.99
c = 70.39γ = 90
Software Package:
Software NamePurpose
X-PLORmodel building
TNTrefinement
X-PLORrefinement
X-PLORphasing

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 1995-10-15
    Type: Initial release
  • Version 1.1: 2008-03-24
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Version format compliance
  • Version 1.3: 2019-07-17
    Changes: Data collection, Other, Refinement description
  • Version 1.4: 2019-08-14
    Changes: Data collection, Refinement description
  • Version 1.5: 2021-11-03
    Changes: Database references, Derived calculations
  • Version 1.6: 2024-02-14
    Changes: Data collection