3N4U

app APH(2")-IVa form II


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.2 Å
  • R-Value Free: 0.273 
  • R-Value Work: 0.178 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

Crystal structure and kinetic mechanism of aminoglycoside phosphotransferase-2''-IVa.

Toth, M.Frase, H.Antunes, N.T.Smith, C.A.Vakulenko, S.B.

(2010) Protein Sci. 19: 1565-1576

  • DOI: 10.1002/pro.437
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • Acquired resistance to aminoglycoside antibiotics primarily results from deactivation by three families of aminoglycoside-modifying enzymes. Here, we report the kinetic mechanism and structure of the aminoglycoside phosphotransferase 2''-IVa (APH(2'' ...

    Acquired resistance to aminoglycoside antibiotics primarily results from deactivation by three families of aminoglycoside-modifying enzymes. Here, we report the kinetic mechanism and structure of the aminoglycoside phosphotransferase 2''-IVa (APH(2'')-IVa), an enzyme responsible for resistance to aminoglycoside antibiotics in clinical enterococcal and staphylococcal isolates. The enzyme operates via a Bi-Bi sequential mechanism in which the two substrates (ATP or GTP and an aminoglycoside) bind in a random manner. The APH(2'')-IVa enzyme phosphorylates various 4,6-disubstituted aminoglycoside antibiotics with catalytic efficiencies (k(cat)/K(m)) of 1.5 x 10(3) to 1.2 x 10(6) (M(-1) s(-1)). The enzyme uses both ATP and GTP as the phosphate source, an extremely rare occurrence in the phosphotransferase and protein kinase enzymes. Based on an analysis of the APH(2'')-IVa structure, two overlapping binding templates specifically tuned for hydrogen bonding to either ATP or GTP have been identified and described. A detailed understanding of the structure and mechanism of the GTP-utilizing phosphotransferases is crucial for the development of either novel aminoglycosides or, more importantly, GTP-based enzyme inhibitors which would not be expected to interfere with crucial ATP-dependent enzymes.


    Organizational Affiliation

    Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
APH(2'')-Id
A
301Enterococcus casseliflavusMutation(s): 0 
Gene Names: aph(2'')-Id
Find proteins for O68183 (Enterococcus casseliflavus)
Go to UniProtKB:  O68183
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.2 Å
  • R-Value Free: 0.273 
  • R-Value Work: 0.178 
  • Space Group: P 21 21 21
Unit Cell:
Length (Å)Angle (°)
a = 46.380α = 90.00
b = 62.590β = 90.00
c = 96.490γ = 90.00
Software Package:
Software NamePurpose
Blu-Icedata collection
MOLREPphasing
XSCALEdata scaling
XDSdata reduction
PHENIXrefinement

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2010-06-30
    Type: Initial release
  • Version 1.1: 2011-07-13
    Type: Version format compliance