Monitoring surface chemistry changes in the bacterial cell wall: multivariate analysis of Cryo-X-ray photoelectron spectroscopy data
2011 (English)In: Journal of Biological Chemistry, ISSN 0021-9258, E-ISSN 1083-351X, Vol. 286, no 14, 12389-12396 p.Article in journal (Refereed) Published
Gram-negative bacteria can alter the composition of the Lipopolysaccharide (LPS) layer of the outer membrane as a response to different growth conditions and external stimuli. These alterations can, for example, promote attachment to surfaces and biofilm formation. The changes occur in the outermost layer of the cell and may consequently influence interactions between bacterial cells and surrounding host tissue, as well as other surfaces. Microscopic analyses, fractionation of bacterial cells or other traditional microbiological assays have previously been used to study these alterations. These methods can, however, be time consuming and do not always give detailed chemical information about the bacterial cell surface. We here present an analytical method that provides chemical information on the outermost portion of bacterial cells with respect to protein, peptidoglycan, lipid and polysaccharide content. The method involves cryo-X-ray Photoelectron Spectroscopy (XPS) analyses of the outermost portion (within ~10 nm of the surface) of intact bacterial cells, followed by a multivariate curve resolution analysis of carbon spectra. It can be used as a tool for characterizing and monitoring variations in the chemical composition of bacterial cell walls or of isolated outer membrane vesicles, variations that result from e.g. mutations or external stimuli. The method enabled us to accurately predict the alterations in polysaccharide content and surface chemistries of a set of well characterized Escherichia coli LPS mutants. The described approach may moreover be applied to monitor surface chemical composition of other biological samples.
Place, publisher, year, edition, pages
2011. Vol. 286, no 14, 12389-12396 p.
Bacteria, Carbohydrate, Cell Surface, Cell Wall, Lipid, Peptides, Spectroscopy, Chemical Composition, Multivariate Analysis, X-ray Photoelectron Spectroscopy
Medical Biotechnology (with a focus on Cell Biology (including Stem Cell Biology), Molecular Biology, Microbiology, Biochemistry or Biopharmacy)
IdentifiersURN: urn:nbn:se:umu:diva-40399DOI: 10.1074/jbc.M110.209536PubMedID: 21330374OAI: oai:DiVA.org:umu-40399DiVA: diva2:402915