6NND image
Entry Detail
PDB ID:
6NND
Title:
Structure of Dihydrofolate reductase from Mycobacterium tuberculosis in complex with NADPH and dihydrofolate
Biological Source:
PDB Version:
Deposition Date:
2019-01-14
Release Date:
2019-07-17
Method Details:
Experimental Method:
Resolution:
1.70 Å
R-Value Free:
0.20
R-Value Work:
0.17
R-Value Observed:
0.17
Space Group:
P 21 21 21
Macromolecular Entities
Polymer Type:polypeptide(L)
Description:Dihydrofolate reductase
Chain IDs:A, B
Chain Length:159
Number of Molecules:2
Biological Source:Mycobacterium tuberculosis (strain ATCC 25618 / H37Rv)
Primary Citation
Crystal structures of the closed form of Mycobacterium tuberculosis dihydrofolate reductase in complex with dihydrofolate and antifolates.
Acta Crystallogr D Struct Biol 75 682 693 (2019)
PMID: 31282477 DOI: 10.1107/S205979831900901X

Abstact

Tuberculosis is a disease caused by Mycobacterium tuberculosis and is the leading cause of death from a single infectious pathogen, with a high prevalence in developing countries in Africa and Asia. There still is a need for the development or repurposing of novel therapies to combat this disease owing to the long-term nature of current therapies and because of the number of reported resistant strains. Here, structures of dihydrofolate reductase from M. tuberculosis (MtDHFR), which is a key target of the folate pathway, are reported in complex with four antifolates, pyrimethamine, cycloguanil, diaverdine and pemetrexed, and its substrate dihydrofolate in order to understand their binding modes. The structures of all of these complexes were obtained in the closed-conformation state of the enzyme and a fine structural analysis indicated motion in key regions of the substrate-binding site and different binding modes of the ligands. In addition, the affinities, through Kd measurement, of diaverdine and methotrexate have been determined; MtDHFR has a lower affinity (highest Kd) for diaverdine than pyrimethamine and trimethoprim, and a very high affinity for methotrexate, as expected. The structural comparisons and analysis described in this work provide new information about the plasticity of MtDHFR and the binding effects of different antifolates.

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Primary Citation of related structures