Interactions of E. coli with cylindrical micro-pillars of different geometric modifications

Venkata Rao Krishnamurthi; Nathaniel Harris; Ariel Rogers; Min Zou; Yong Wang

doi:10.1016/j.colsurfb.2021.112190

Interactions of E. coli with cylindrical micro-pillars of different geometric modifications

Colloids Surf B Biointerfaces. 2022 Jan;209(Pt 2):112190. doi: 10.1016/j.colsurfb.2021.112190. Epub 2021 Oct 30.

Authors

Venkata Rao Krishnamurthi¹, Nathaniel Harris², Ariel Rogers¹, Min Zou³, Yong Wang⁴

Affiliations

¹ Department of Physics, University of Arkansas, Fayetteville, AR 72701, USA.
² Department of Mechanical Engineering, University of Arkansas, Fayetteville, AR 72701, USA.
³ Department of Mechanical Engineering, University of Arkansas, Fayetteville, AR 72701, USA; Materials Science and Engineering Program, University of Arkansas, Fayetteville, AR 72701, USA.
⁴ Department of Physics, University of Arkansas, Fayetteville, AR 72701, USA; Materials Science and Engineering Program, University of Arkansas, Fayetteville, AR 72701, USA; Cell and Molecular Biology Program, University of Arkansas, Fayetteville, AR 72701, USA. Electronic address: yongwang@uark.edu.

PMID: 34749195
DOI: 10.1016/j.colsurfb.2021.112190

Abstract

Understanding the behavior of bacteria at the proximity of different surfaces is of great importance and interest. Despite recent exciting progress in geometric control of bacterial behavior around surfaces, a detailed comparison on the interaction of bacteria with cylindrical surfaces of different geometric modifications is still missing. Here, we investigated how bacteria interacted with cylindrical micro-pillars and modified cylindrical micro-pillars with sprocket, gear, and flower-like wall surface features. Using phase-contrast microscopy, we examined the motion of bacteria around the micro-pillars, and observed different responses of bacteria to each geometric modification. In addition, we extracted the trajectories of the bacteria and characterized several parameters (instantaneous velocity v, change of direction δ, approaching angle ϕ) to quantitatively compare the effects of the geometric modifications on the micro-pillars. We found that sharp spikes showed the largest effect, compared to smooth surface, convex and concave ripples. Lastly, we carried out numerical simulations, which explained the experimental observations and showed that the observed effects were due to the geometric modifications.

Keywords: 3D printing; geometry; microstructures; surface; two-photon polymerization.

MeSH terms

Escherichia coli*