Advertisement

Journal of Molecular Evolution

, Volume 48, Issue 1, pp 22–41 | Cite as

Getting In or Out: Early Segregation Between Importers and Exporters in the Evolution of ATP-Binding Cassette (ABC) Transporters

  • William  Saurin
  • Maurice  Hofnung
  • Elie  Dassa

Abstract.

ATP-binding cassette (ABC) systems, also called traffic ATPases, are found in eukaryotes and prokaryotes and almost all participate in the transport of a wide variety of molecules. ABC systems are characterized by a highly conserved ATPase module called here the ABC module, involved in coupling transport to ATP hydrolysis. We have used the sequence of one of the first representatives of bacterial ABC transporters, the MalK protein, to collect 250 closely related sequences from a nonredundant protein sequence database. The sequences collected by this objective method are all known or putative ABC transporters. After having eliminated short protein sequences and duplicates, the 197 remaining sequences were subjected to a phylogenetic analysis based on a mutational similarity matrix. An unrooted tree for these modules was found to display two major branches, one grouping all collected uptake systems and the other all collected export systems. This remarkable disposition strongly suggests that the divergence between these two functionally different types of ABC systems occurred once in the history of these systems and probably before the differentiation of prokaryotes and eukaryotes. We discuss the implications of this finding and we propose a model accounting for the generation and the diversification of ABC systems.

Key words: ABC transporters — Binding protein-dependent transporters — Computational analysis — Membrane proteins — ATPase — Multidrug resistance — Cystic fibrosis — Adrenoleukodystrophy 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

Copyright information

© Springer-Verlag New York Inc. 1999

Authors and Affiliations

  • William  Saurin
    • 1
  • Maurice  Hofnung
    • 1
  • Elie  Dassa
    • 1
  1. 1.Unité de Programmation Moléculaire et Toxicologie génétique, CNRS URA 1444, Institut Pasteur, 25 Rue du Dr. Roux, F75724 Paris Cedex 15, FranceFR

Personalised recommendations