1BMD

DETERMINANTS OF PROTEIN THERMOSTABILITY OBSERVED IN THE 1.9 ANGSTROMS CRYSTAL STRUCTURE OF MALATE DEHYDROGENASE FROM THE THERMOPHILIC BACTERIUM THERMUS FLAVUS


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.90 Å
  • R-Value Work: 0.154 
  • R-Value Observed: 0.154 

wwPDB Validation   3D Report Full Report


This is version 1.6 of the entry. See complete history


Literature

Determinants of protein thermostability observed in the 1.9-A crystal structure of malate dehydrogenase from the thermophilic bacterium Thermus flavus.

Kelly, C.A.Nishiyama, M.Ohnishi, Y.Beppu, T.Birktoft, J.J.

(1993) Biochemistry 32: 3913-3922

  • DOI: https://doi.org/10.1021/bi00066a010
  • Primary Citation of Related Structures:  
    1BDM, 1BMD

  • PubMed Abstract: 

    A binary complex of malate dehydrogenase from the thermophilic bacterium Thermus flavus (tMDH) with NADH has been crystallized from poly(ethylene glycol) 3500, pH 8.5, yielding diffraction-quality crystals in space group P2(1)2(1)2(1). The structure was solved at 1.9-A resolution using molecular replacement and refined to an R factor of 15.8% with good geometry. The primary sequence of tMDH is 55% identical to that of cytoplasmic malate dehydrogenase (cMDH) [Birktoft, J. J., Rhodes, G., & Banaszak, L. J. (1989) Biochemistry 28, 6065-6081], and overall their three-dimensional structures are very similar. Like cMDH, tMDH crystallized as a dimer with one coenzyme bound per subunit. The coenzyme binds in the extended conformation, and most of the interactions with enzyme are similar to those in cMDH. In tMDH, small local conformational changes are caused by the replacement of a glutamic acid for the aspartic acid involved in hydrogen bonding to the adenine ribose of NADH. Comparison of tMDH with cMDH reveals that both tMDH subunits more closely resemble the B subunit of cMDH which therefore is the more likely representative of the solution conformation. While cMDH is inactivated at temperatures above about 50 degrees C, tMDH is fully active at 90 degrees C. On the basis of the X-ray crystal structure, a number of factors have been identified which are likely to contribute to the relative thermostability of tMDH compared to cMDH. The most striking of the differences involves the introduction of four ion pairs per monomer. All of these ion pairs are solvent-accessible. Three of these ion pairs are located in the dimer interface, Glu27-Lys31, Glu57-Lys168, and Glu57-Arg229, and one ion pair, Glu275-Arg149, is at the domain interface within each subunit. Additionally, we observe incorporation of additional alanines into alpha-helices of tMDH and, in one instance, incorporation of an aspartate that functions as a counterchange to an alpha-helix dipole. The possible contributions of these and other factors to protein thermostability in tMDH are discussed.


  • Organizational Affiliation

    Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, Missouri 63110.


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
MALATE DEHYDROGENASE
A, B
327Thermus thermophilusMutation(s): 0 
EC: 1.1.1.37
UniProt
Find proteins for P10584 (Thermus thermophilus)
Explore P10584 
Go to UniProtKB:  P10584
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP10584
Sequence Annotations
Expand
  • Reference Sequence
Small Molecules
Ligands 1 Unique
IDChains Name / Formula / InChI Key2D Diagram3D Interactions
NAD
Query on NAD

Download Ideal Coordinates CCD File 
C [auth A],
D [auth B]
NICOTINAMIDE-ADENINE-DINUCLEOTIDE
C21 H27 N7 O14 P2
BAWFJGJZGIEFAR-NNYOXOHSSA-N
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.90 Å
  • R-Value Work: 0.154 
  • R-Value Observed: 0.154 
  • Space Group: P 21 21 21
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 71.51α = 90
b = 87.59β = 90
c = 118.98γ = 90
Software Package:
Software NamePurpose
X-PLORmodel building
TNTrefinement
X-PLORrefinement
X-PLORphasing

Structure Validation

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Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 1994-07-31
    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: 2017-11-29
    Changes: Derived calculations, Other
  • Version 1.4: 2019-07-17
    Changes: Data collection, Refinement description
  • Version 1.5: 2019-08-14
    Changes: Data collection, Refinement description
  • Version 1.6: 2024-02-07
    Changes: Data collection, Database references, Derived calculations