Correlative Imaging of Structural and Elemental Composition of Bacterial Biofilms

Y Yang,R Heine,T Gorniak,L Helfen,A Rosenhahn,H Suhonen,S Kirchen,F Xu,T Schwartz,T Baumbach

doi:10.1088/1742-6596/463/1/012053

Abstract

Synchrotron-based phase contrast tomography (holotomography) and scanning hard X-ray fluorescence microscopy (SXFM) are combined to characterize the three-dimensional (3D) structural and corresponding elemental distribution of bacterial biofilms of Pseudomonas aeruginosa. Samples were fixed without contrast agents or microtomal sectioning. Within an intact microbial community single bacteria are clearly resolved, and their morphology can be directly visualized together with the elemental content. Such 3D set of complementary information at cellular level is essential for gaining a deeper understanding of biofilm evolution aiming to develop potential strategies on biofilm growth control and prevention.

Highlights

Bacterial biofilms are broadly defined as structured, multicellular communities of bacteria that are enclosed in an exopolymeric matrix and attached to a surface [1]
The scanning hard X-ray fluorescence microscopy (SXFM) and holotomography measurements have been performed at the nano-imaging end station of beamline ID22 at the European Synchrotron Radiation Facility (ESRF)
The bacteria are well resolved in the fluorescence micrographs (see Figs. 3 (b) and (c) for the distribution of two selected elements) and their morphology is reproduced by the holotomogram (Figs. 3 (a) and (e))

Summary

Introduction

Bacterial biofilms are broadly defined as structured, multicellular communities of bacteria that are enclosed in an exopolymeric matrix and attached to a surface [1]. Many bacteria are well-known for their robustness against antimicrobial agents. This manifests itself in health care where contamination of medical implants and wounds poses a severe threat to human health. Biofilms show remarkable resistance to wetting [6], gas penetration [6], and uptake of heavy metals like copper, lead and zinc [7]. In this context it is important to understand which mechanisms allow this complex matrix to be robust to such an extent

Methods

Results

Conclusion