Probing nanostructures of bacterial extracellular polymeric substances versus culture time by Raman microspectroscopy and atomic force microscopy

  • McEwen G
  • Wu Y
  • Zhou A
  • 19


    Mendeley users who have this article in their library.
  • 9


    Citations of this article.


The structure of a bacterial cell wall may alter during bacterial reproduction. Moreover, these cell wall variations, on a nanoscale resolution, have not yet fully been elucidated. In this work, Raman spectroscopy and atomic force microscopy (AFM) technique are applied to evaluate the culture time-dependent cell wall structure variations of Pseudomonas putida KT2440 at a quorum and single cell level. The Raman spectra indicate that the appearance of DNA/RNA, protein, lipid, and carbohydrates occurs till 6 h of cultivation time under our experimental conditions. AFM characterization reveals the changes of the cellular surface ultrastructures over the culture time period, which is a gradual increase in surface roughness during the time between the first two and eight hours cultivation time. This work demonstrates the feasibility of utilizing a combined Raman spectroscopy and AFM technique to investigate the cultivation time dependence of bacterial cellular surface biopolymers at single cell level.

Author-supplied keywords

  • Atomic force microscopy
  • Extracellular polymeric substances
  • Pseudomonas putida KT2440
  • Raman spectroscopy

Get free article suggestions today

Mendeley saves you time finding and organizing research

Sign up here
Already have an account ?Sign in

Find this document


  • Gerald D. McEwen

  • Yangzhe Wu

  • Anhong Zhou

Cite this document

Choose a citation style from the tabs below

Save time finding and organizing research with Mendeley

Sign up for free