1KPG

Crystal Structure of mycolic acid cyclopropane synthase CmaA1 complexed with SAH and CTAB


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.00 Å
  • R-Value Free: 0.233 
  • R-Value Work: 0.191 
  • R-Value Observed: 0.191 

wwPDB Validation   3D Report Full Report


This is version 1.2 of the entry. See complete history


Literature

Crystal structures of mycolic acid cyclopropane synthases from Mycobacterium tuberculosis

Huang, C.-C.Smith, C.V.Glickman, M.S.Jacobs Jr., W.R.Sacchettini, J.C.

(2002) J Biol Chem 277: 11559-11569

  • DOI: 10.1074/jbc.M111698200
  • Primary Citation of Related Structures:  
    1KPI, 1KPH, 1KPG, 1KP9, 1L1E

  • PubMed Abstract: 
  • Mycolic acids are major components of the cell wall of Mycobacterium tuberculosis. Several studies indicate that functional groups in the acyl chain of mycolic acids are important for pathogenesis and persistence. There are at least three mycolic acid cyclopropane synthases (PcaA, CmaA1, and CmaA2) that are responsible for these site-specific modifications of mycolic acids ...

    Mycolic acids are major components of the cell wall of Mycobacterium tuberculosis. Several studies indicate that functional groups in the acyl chain of mycolic acids are important for pathogenesis and persistence. There are at least three mycolic acid cyclopropane synthases (PcaA, CmaA1, and CmaA2) that are responsible for these site-specific modifications of mycolic acids. To derive information on the specificity and enzyme mechanism of the family of proteins, the crystal structures of CmaA1, CmaA2, and PcaA were solved to 2-, 2-, and 2.65-A resolution, respectively. All three enzymes have a seven-stranded alpha/beta fold similar to other methyltransferases with the location and interactions with the cofactor S-adenosyl-l-methionine conserved. The structures of the ternary complexes demonstrate the position of the mycolic acid substrate binding site. Close examination of the active site reveals electron density that we believe represents a bicarbonate ion. The structures support the hypothesis that these enzymes catalyze methyl transfer via a carbocation mechanism in which the bicarbonate ion acts as a general base. In addition, comparison of the enzyme structures reveals a possible mechanism for substrate specificity. These structures provide a foundation for rational-drug design, which may lead to the development of new inhibitors effective against persistent bacteria.


    Organizational Affiliation

    Department of Biochemistry and Biophysics, Texas A&M University, College Station, Texas 77843-2128, USA.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
CYCLOPROPANE-FATTY-ACYL-PHOSPHOLIPID SYNTHASE 1A, B, C, D287Mycobacterium tuberculosisMutation(s): 0 
Gene Names: cmaA1
EC: 2.1.1.79
Find proteins for P9WPB7 (Mycobacterium tuberculosis (strain ATCC 25618 / H37Rv))
Explore P9WPB7 
Go to UniProtKB:  P9WPB7
Protein Feature View
Expand
  • Reference Sequence
Small Molecules
Modified Residues  1 Unique
IDChainsTypeFormula2D DiagramParent
MSE
Query on MSE
A, B, C, DL-PEPTIDE LINKINGC5 H11 N O2 SeMET
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.00 Å
  • R-Value Free: 0.233 
  • R-Value Work: 0.191 
  • R-Value Observed: 0.191 
  • Space Group: P 43
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 77.323α = 90
b = 77.323β = 90
c = 173.49γ = 90
Software Package:
Software NamePurpose
DENZOdata reduction
SCALEPACKdata scaling
SHARPphasing
CNSrefinement

Structure Validation

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Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2002-01-11
    Type: Initial release
  • Version 1.1: 2008-04-27
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Version format compliance