Replacement of the human topoisomerase linker domain with the plasmodial counterpart renders the enzyme camptothecin resistant

Barbara Arnò; Ilda D'Annessa; Cinzia Tesauro; Laura Zuccaro; Alessio Ottaviani; Birgitta Knudsen; Paola Fiorani; Alessandro Desideri

doi:10.1371/journal.pone.0068404

Replacement of the human topoisomerase linker domain with the plasmodial counterpart renders the enzyme camptothecin resistant

PLoS One. 2013 Jul 2;8(7):e68404. doi: 10.1371/journal.pone.0068404. Print 2013.

Authors

Barbara Arnò¹, Ilda D'Annessa, Cinzia Tesauro, Laura Zuccaro, Alessio Ottaviani, Birgitta Knudsen, Paola Fiorani, Alessandro Desideri

Affiliation

¹ Department of Biology and Interuniversity Consortium, National Institute Biostructure and Biosystem, University of Rome Tor Vergata, Rome, Italy.

Abstract

A human/plasmodial hybrid enzyme, generated by swapping the human topoisomerase IB linker domain with the corresponding domain of the Plasmodium falciparum enzyme, has been produced and characterized. The hybrid enzyme displays a relaxation activity comparable to the human enzyme, but it is characterized by a much faster religation rate. The hybrid enzyme is also camptothecin resistant. A 3D structure of the hybrid enzyme has been built and its structural-dynamical properties have been analyzed by molecular dynamics simulation. The analysis indicates that the swapped plasmodial linker samples a conformational space much larger than the corresponding domain in the human enzyme. The large linker conformational variability is then linked to important functional properties such as an increased religation rate and a low drug reactivity, demonstrating that the linker domain has a crucial role in the modulation of the topoisomerase IB activity.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Binding Sites / genetics
Biocatalysis / drug effects
Camptothecin / pharmacology*
DNA Topoisomerases, Type I / chemistry
DNA Topoisomerases, Type I / genetics*
DNA Topoisomerases, Type I / metabolism
DNA, Superhelical / chemistry
DNA, Superhelical / metabolism
Humans
Models, Molecular
Molecular Dynamics Simulation
Plasmodium falciparum / enzymology
Plasmodium falciparum / genetics
Principal Component Analysis
Protein Engineering / methods
Protein Structure, Tertiary
Protozoan Proteins / chemistry
Protozoan Proteins / genetics*
Protozoan Proteins / metabolism
Recombinant Fusion Proteins / chemistry
Recombinant Fusion Proteins / genetics*
Recombinant Fusion Proteins / metabolism
Substrate Specificity
Topoisomerase I Inhibitors / pharmacology

Substances

DNA, Superhelical
Protozoan Proteins
Recombinant Fusion Proteins
Topoisomerase I Inhibitors
DNA Topoisomerases, Type I
TOP1 protein, human
Camptothecin

Grants and funding

This work has been supported by the AIRC project 10121 to A.D. and the Minister Erna Hamiltons Grant for Science and Art to B.K. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.