6B5K

Mycobacterium tuberculosis RmlA in complex with Mg/dTTP


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.60 Å
  • R-Value Free: 0.227 
  • R-Value Work: 0.195 
  • R-Value Observed: 0.196 

wwPDB Validation   3D Report Full Report


Ligand Structure Quality Assessment 


This is version 1.1 of the entry. See complete history


Literature

The structure of glucose-1-phosphate thymidylyltransferase from Mycobacterium tuberculosis reveals the location of an essential magnesium ion in the RmlA-type enzymes.

Brown, H.A.Thoden, J.B.Tipton, P.A.Holden, H.M.

(2018) Protein Sci 27: 441-450

  • DOI: 10.1002/pro.3333
  • Primary Citation of Related Structures:  
    6B5E, 6B5K

  • PubMed Abstract: 
  • Tuberculosis, caused by the bacterium Mycobacterium tuberculosis, continues to be a major threat to populations worldwide. Whereas the disease is treatable, the drug regimen is arduous at best with the use of four antimicrobials over a six-month period. There is clearly a pressing need for the development of new therapeutics ...

    Tuberculosis, caused by the bacterium Mycobacterium tuberculosis, continues to be a major threat to populations worldwide. Whereas the disease is treatable, the drug regimen is arduous at best with the use of four antimicrobials over a six-month period. There is clearly a pressing need for the development of new therapeutics. One potential target for structure-based drug design is the enzyme RmlA, a glucose-1-phosphate thymidylyltransferase. This enzyme catalyzes the first step in the biosynthesis of l-rhamnose, which is a deoxysugar critical for the integrity of the bacterium's cell wall. Here, we report the X-ray structures of M. tuberculosis RmlA in complex with either dTTP or dTDP-glucose to 1.6 Å and 1.85 Å resolution, respectively. In the RmlA/dTTP complex, two magnesium ions were observed binding to the nucleotide, both ligated in octahedral coordination spheres. In the RmlA/dTDP-glucose complex, only a single magnesium ion was observed. Importantly, for RmlA-type enzymes with known three-dimensional structures, not one model shows the position of the magnesium ion bound to the nucleotide-linked sugar. As such, this investigation represents the first direct observation of the manner in which a magnesium ion is coordinated to the RmlA product and thus has important ramifications for structure-based drug design. In the past, molecular modeling procedures have been employed to derive a three-dimensional model of the M. tuberculosis RmlA for drug design. The X-ray structures presented herein provide a superior molecular scaffold for such endeavors in the treatment of one of the world's deadliest diseases.


    Organizational Affiliation

    Department of Biochemistry, University of Wisconsin, Madison, WI, 53706, USA.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
Glucose-1-phosphate thymidylyltransferaseA, B296Mycobacterium tuberculosis H37RvMutation(s): 0 
Gene Names: rmlArfbARv0334
EC: 2.7.7.24
UniProt
Find proteins for P9WH13 (Mycobacterium tuberculosis (strain ATCC 25618 / H37Rv))
Explore P9WH13 
Go to UniProtKB:  P9WH13
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP9WH13
Protein Feature View
Expand
  • Reference Sequence
Small Molecules
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.60 Å
  • R-Value Free: 0.227 
  • R-Value Work: 0.195 
  • R-Value Observed: 0.196 
  • Space Group: I 4
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 96.403α = 90
b = 96.403β = 90
c = 151.924γ = 90
Software Package:
Software NamePurpose
REFMACrefinement
HKL-3000data reduction
HKL-3000data scaling
PHASERphasing

Structure Validation

View Full Validation Report



Ligand Structure Quality Assessment 



Entry History & Funding Information

Deposition Data


Funding OrganizationLocationGrant Number
National Institutes of Health/National Institute of General Medical Sciences (NIH/NIGMS)United StatesGM115921

Revision History  (Full details and data files)

  • Version 1.0: 2018-02-21
    Type: Initial release
  • Version 1.1: 2020-01-01
    Changes: Author supporting evidence