סמינר בכימיה פיזיקלית: Uncovering molecular processes that shape biofilms’ mechanics, structure and function

Abstract:

Biofilms are multicellular microbial communities that encase themselves in a secreted network of biopolymers and attach to surfaces and interfaces. From a soft matter physics perspective, biofilms are considered as complex living materials resembling colloidal hydrogels. However, from a biological perspective, biofilms are heterogeneous cellular communities that organize in space and time into functionally distinct populations, in a process resembling differentiation in higher organisms. While biofilm heterogeneity has been appreciated at the cellular level, the molecular level has been largely overlooked. In this talk, I will show how the molecular biochemistry and soft matter properties of biofilms are tightly linked and together lead to biological processes occurring at different length scales. Using a broad range of multiscale biophysical methods, among which are simultaneous synchrotron X-ray diffraction/fluorescence (XRD/XRF), atomic force microscopy (AFM), and cryo-electron microscopy/tomography, we portrayed the dominant structural and compositional features in living Bacillus subtilis biofilms and mapped them in space and time. The uncovered relationships between molecular-level spatial distribution of ECM, metal ions and cellular differentiation lead us to suggest an inclusive view of biofilm development, where molecular-level heterogeneity is directly shaping biofilm physiology. Our results not only advance understanding of fundamental principles of biofilm organisation but also open new avenues for their control and deployment in materials science and bioengineering applications.

References:

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4. e2118107119 (2022) (4) J. Böhning, M. Ghrayeb, C. Pedebos, DK. Abbas, S. Khalid, L. Chai*, T. Bhrarat*, Donor-strand exchange drives assembly of the TasA scaffold in Bacillus subtilis biofilms. Nature Communications, 13, 7082 (2022) *Corresponding authors.

מארגנת הסמינר: ד"ר אנאל בן אשר