AFM imaging of bacteria in liquid media immobilized on gelatin coated mica surfaces

M. J. Doktycz, C. J. Sullivan, P. R. Hoyt, D. A. Pelletier, S. Wu, D. P. Allison

Research output: Contribution to journalArticlepeer-review

200 Scopus citations

Abstract

Immobilization of particulates, especially biomolecules and cells, onto surfaces is critical for imaging with the atomic force microscope (AFM). In this paper, gelatin coated mica surfaces are shown to be suitable for immobilizing and imaging both gram positive, Staphylococcus aureus, and gram negative, Escherichia coli, bacteria in both air and liquid environments. Gelatin coated surfaces are shown to be superior to poly-L-lysine coated surfaces that are commonly used for the immobilization of cells. This cell immobilization technique is being developed primarily for live cell imaging of Rhodopseudomonas palustris. The genome of R. palustris has been sequenced and the organism is the target of intensive studies aimed at understanding genome function. Images of R. palustris grown both aerobically and anaerobically in liquid media are presented. Images in liquid media show the bacteria is rod shaped and smooth while images in air show marked irregularity and folding of the surface. Significant differences in the vertical dimension are also apparent with the height of the bacteria in liquid being substantially greater than images taken in air. In air immobilized bacterial flagella are clearly seen while in liquid this structure is not visible. Additionally, significant morphological differences are observed that depend on the method of bacterial growth.

Original languageEnglish
Pages (from-to)209-216
Number of pages8
JournalUltramicroscopy
Volume97
Issue number1-4
DOIs
StatePublished - 2003

Funding

This research was sponsored by the Office of Biological and Environmental Research, US Department of Energy. Oak Ridge National Laboratory is managed by UT-Battelle, LLC, for the US Department of Energy under Contract No. DE-AC05-00OR22725.

Keywords

  • Atomic force microscopy
  • Bacteria
  • Cell immobilization
  • Gelatin
  • In situ microscopy
  • MacMode
  • Rhodopseudomonas palustris

Fingerprint

Dive into the research topics of 'AFM imaging of bacteria in liquid media immobilized on gelatin coated mica surfaces'. Together they form a unique fingerprint.

Cite this