1J49

INSIGHTS INTO DOMAIN CLOSURE, SUBSTRATE SPECIFICITY AND CATALYSIS OF D-LACTATE DEHYDROGENASE FROM LACTOBACILLUS BULGARICUS


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.2 Å
  • R-Value Free: 0.271 
  • R-Value Work: 0.207 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Domain closure, substrate specificity and catalysis of D-lactate dehydrogenase from Lactobacillus bulgaricus.

Razeto, A.Kochhar, S.Hottinger, H.Dauter, M.Wilson, K.S.Lamzin, V.S.

(2002) J.Mol.Biol. 318: 109-119

  • DOI: 10.1016/S0022-2836(02)00086-4
  • Primary Citation of Related Structures:  1J4A

  • PubMed Abstract: 
  • NAD-dependent Lactobacillus bulgaricus D-Lactate dehydrogenase (D-LDHb) catalyses the reversible conversion of pyruvate into D-lactate. Crystals of D-LDHb complexed with NADH were grown and X-ray data collected to 2.2 A. The structure of D-LDHb was s ...

    NAD-dependent Lactobacillus bulgaricus D-Lactate dehydrogenase (D-LDHb) catalyses the reversible conversion of pyruvate into D-lactate. Crystals of D-LDHb complexed with NADH were grown and X-ray data collected to 2.2 A. The structure of D-LDHb was solved by molecular replacement using the dimeric Lactobacillus helveticus D-LDH as a model and was refined to an R-factor of 20.7%. The two subunits of the enzyme display strong asymmetry due to different crystal environments. The opening angles of the two catalytic domains with respect to the core coenzyme binding domains differ by 16 degrees. Subunit A is in an "open" conformation typical for a dehydrogenase apo enzyme and subunit B is "closed". The NADH-binding site in subunit A is only 30% occupied, while in subunit B it is fully occupied and there is a sulphate ion in the substrate-binding pocket. A pyruvate molecule has been modelled in the active site and its orientation is in agreement with existing kinetic and structural data. On domain closure, a cluster of hydrophobic residues packs tightly around the methyl group of the modelled pyruvate molecule. At least three residues from this cluster govern the substrate specificity. Substrate binding itself contributes to the stabilisation of domain closure and activation of the enzyme. In pyruvate reduction, D-LDH can adapt another protonated residue, a lysine residue, to accomplish the role of the acid catalyst His296. Required lowering of the lysine pK(a) value is explained on the basis of the H296K mutant structure.


    Organizational Affiliation

    European Molecular Biology Laboratory Hamburg Outstation, c/o DESY, Notkestrasse 85, 22603 Hamburg, Germany. arazeto@gwdg.de




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
D-LACTATE DEHYDROGENASE
A, B
333Lactobacillus delbrueckii subsp. bulgaricus (strain ATCC 11842 / DSM 20081 / JCM 1002 / NBRC 13953 / NCIMB 11778)Gene Names: ldhA
EC: 1.1.1.28
Find proteins for P26297 (Lactobacillus delbrueckii subsp. bulgaricus (strain ATCC 11842 / DSM 20081 / JCM 1002 / NBRC 13953 / NCIMB 11778))
Go to UniProtKB:  P26297
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
SO4
Query on SO4

Download SDF File 
Download CCD File 
B
SULFATE ION
O4 S
QAOWNCQODCNURD-UHFFFAOYSA-L
 Ligand Interaction
NAD
Query on NAD

Download SDF File 
Download CCD File 
A, B
NICOTINAMIDE-ADENINE-DINUCLEOTIDE
C21 H27 N7 O14 P2
BAWFJGJZGIEFAR-NNYOXOHSSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.2 Å
  • R-Value Free: 0.271 
  • R-Value Work: 0.207 
  • Space Group: P 43 21 2
Unit Cell:
Length (Å)Angle (°)
a = 79.400α = 90.00
b = 79.400β = 90.00
c = 228.500γ = 90.00
Software Package:
Software NamePurpose
REFMACrefinement
DENZOdata reduction
SCALEPACKdata scaling
AMoREphasing

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2002-05-29
    Type: Initial release
  • Version 1.1: 2008-04-26
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance