Endocytosis-like protein uptake in the bacterium Gemmata obscuriglobus

Proc Natl Acad Sci U S A. 2010 Jul 20;107(29):12883-8. doi: 10.1073/pnas.1001085107. Epub 2010 Jun 21.

Abstract

Endocytosis is a process by which extracellular material such as macromolecules can be incorporated into cells via a membrane-trafficking system. Although universal among eukaryotes, endocytosis has not been identified in Bacteria or Archaea. However, intracellular membranes are known to compartmentalize cells of bacteria in the phylum Planctomycetes, suggesting the potential for endocytosis and membrane trafficking in members of this phylum. Here we show that cells of the planctomycete Gemmata obscuriglobus have the ability to uptake proteins present in the external milieu in an energy-dependent process analogous to eukaryotic endocytosis, and that internalized proteins are associated with vesicle membranes. Occurrence of such ability in a bacterium is consistent with autogenous evolution of endocytosis and the endomembrane system in an ancestral noneukaryote cell.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bacteria / cytology*
  • Bacteria / metabolism*
  • Bacteria / ultrastructure
  • Bacterial Proteins / metabolism*
  • Biological Evolution
  • Cell Compartmentation
  • DNA, Bacterial / metabolism
  • Endocytosis*
  • Energy Metabolism
  • Green Fluorescent Proteins
  • Protein Processing, Post-Translational
  • Transport Vesicles / ultrastructure

Substances

  • Bacterial Proteins
  • DNA, Bacterial
  • Green Fluorescent Proteins