Physiochemically distinct SU-8 surfaces tailor Xylella fastidiosa cell-surface holdfast and colonization

Anbumani, S.; Silva, A. M. d.; Alaferdov, A.; Santos, M. V. P. d.; Carvalho, I. G. B.; Silva, M. d. S. e.; Moshkalev, S.; Carvalho, H. F.; Souza, A. A. d.; Cotta, M. A.

doi:10.1101/2021.12.14.472636

bioRxiv · 10.1101/2021.12.14.472636

Physiochemically distinct SU-8 surfaces tailor Xylella fastidiosa cell-surface holdfast and colonization

Anbumani, S.·Silva, A. M. d.·Alaferdov, A.·Santos, M. V. P. d.·Carvalho, I. G. B.·Silva, M. d. S. e.·Moshkalev, S.·Carvalho, H. F.·Souza, A. A. d.·Cotta, M. A.

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Abstract

SU-8 polymer is an excellent platform for diverse applications due to its high aspect ratio of micro/nanostructures fabrication and exceptional optical, chemical, and biocompatible properties. Although SU-8 has been often investigated for a variety of biological applications, how its surface properties influence both the interaction of bacterial cells with the substrate and its colonization is poorly understood. In this work, we tailor SU-8 nanoscale surface properties to investigate single cell motility, adhesion and successive colonization of a phytopathogenic bacteria, Xylella fastidiosa. Different surface properties of SU-8 thin films have been prepared using photolithography processing and oxygen plasma treatment. We found a significant difference in bacterial cell behavior and subsequent colonization on SU-8 as surface property changes. A larger density of carboxyl groups in hydrophilic plasma-treated SU-8 surfaces promotes faster cell motility in the earlier stage of the growth. The hydrophobic nature of pristine SU-8 surfaces has no trackable bacterial motility with 5 to 10 times more single cells adhered to surface than its plasma-treated counterpart. In fact, plasma-treated SU-8 samples suppressed bacterial adhesion, with surfaces showing less than 5% coverage. These results not only showcase that SU-8 surface properties can impact the bacterial behavior in a spatiotemporal manner, but also provide insights on the prominent ability of pathogens to evolve and adapt to different surface properties.

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Anbumani, S., Silva, A. M. d., Alaferdov, A., Santos, M. V. P. d., Carvalho, I. G. B., Silva, M. d. S. e., Moshkalev, S., Carvalho, H. F., Souza, A. A. d., Cotta, M. A.. 2021-12-16. Physiochemically distinct SU-8 surfaces tailor Xylella fastidiosa cell-surface holdfast and colonization. https://doi.org/10.1101/2021.12.14.472636

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