The porin and the permeating antibiotic: a selective diffusion barrier in Gram-negative bacteria

Nat Rev Microbiol. 2008 Dec;6(12):893-903. doi: 10.1038/nrmicro1994. Epub 2008 Nov 10.


Gram-negative bacteria are responsible for a large proportion of antibiotic-resistant bacterial diseases. These bacteria have a complex cell envelope that comprises an outer membrane and an inner membrane that delimit the periplasm. The outer membrane contains various protein channels, called porins, which are involved in the influx of various compounds, including several classes of antibiotics. Bacterial adaptation to reduce influx through porins is an increasing problem worldwide that contributes, together with efflux systems, to the emergence and dissemination of antibiotic resistance. An exciting challenge is to decipher the genetic and molecular basis of membrane impermeability as a bacterial resistance mechanism. This Review outlines the bacterial response towards antibiotic stress on altered membrane permeability and discusses recent advances in molecular approaches that are improving our knowledge of the physico-chemical parameters that govern the translocation of antibiotics through porin channels.

Publication types

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

MeSH terms

  • Animals
  • Anti-Bacterial Agents / pharmacokinetics*
  • Anti-Bacterial Agents / pharmacology*
  • Bacterial Proteins / chemistry
  • Bacterial Proteins / genetics
  • Bacterial Proteins / physiology*
  • Cell Membrane Permeability / drug effects
  • Diffusion
  • Drug Resistance, Bacterial / physiology
  • Gram-Negative Bacteria / drug effects*
  • Gram-Negative Bacteria / genetics
  • Gram-Negative Bacteria / pathogenicity
  • Gram-Negative Bacteria / physiology*
  • Humans
  • Models, Biological
  • Models, Molecular
  • Mutation
  • Porins / chemistry
  • Porins / genetics
  • Porins / physiology*


  • Anti-Bacterial Agents
  • Bacterial Proteins
  • Porins