High‐resolution architecture of the outer membrane of the Gram‐negative bacteria Roseobacter denitrificans
Open Access
- 20 November 2009
- journal article
- research article
- Published by Wiley in Molecular Microbiology
- Vol. 74 (5), 1211-1222
- https://doi.org/10.1111/j.1365-2958.2009.06926.x
Abstract
The outer membrane of Gram-negative bacteria protects the cell against bactericidal substances. Passage of nutrients and waste is assured by outer membrane porins, beta-barrel transmembrane channels. While atomic structures of several porins have been solved, so far little is known on the supramolecular structure of the outer membrane. Here we present the first high-resolution view of a bacterial outer membrane gently purified maintaining remnants of peptidoglycan on the perisplasmic surface. Atomic force microscope images of outer membrane fragments of the size of ∼50% of the bacterial envelope revealed that outer membrane porins are by far more densely packed than previously assumed. Indeed the outer membrane is a molecular sieve rather than a membrane. Porins cover ∼70% of the membrane surface and form locally regular lattices. The potential role of exposed aromatic residues in the formation of the supramolecular assembly is discussed. Finally, we present first structural data of the outer membrane porin from the marine Gram-negative bacteria Roseobacter denitrificans, and we perform a sequence alignment with porins of known structure.Keywords
This publication has 58 references indexed in Scilit:
- Structural Information, Resolution, and Noise in High-Resolution Atomic Force Microscopy TopographsBiophysical Journal, 2009
- Protein secretion and outer membrane assembly inAlphaproteobacteriaFEMS Microbiology Reviews, 2008
- Dynamic control of slow water transport by aquaporin 0: Implications for hydration and junction stability in the eye lensProceedings of the National Academy of Sciences of the United States of America, 2008
- The Preference of Tryptophan for Membrane InterfacesOnline Journal of Public Health Informatics, 2008
- From high-resolution AFM topographs to atomic models of supramolecular assembliesJournal of Structural Biology, 2007
- The Complete Genome Sequence of Roseobacter denitrificans Reveals a Mixotrophic Rather than Photosynthetic MetabolismJournal of Bacteriology, 2007
- MMDB: annotating protein sequences with Entrez's 3D-structure databaseNucleic Acids Research, 2006
- The supramolecular architecture of junctional microdomains in native lens membranesEMBO Reports, 2006
- The Preference of Tryptophan for Membrane InterfacesBiochemistry, 1998
- Aromatic-Aromatic Interaction: A Mechanism of Protein Structure StabilizationScience, 1985