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Title: Surface Topography Hinders Bacterial Surface Motility
We demonstrate that the surface motility of the bacterium, Pseudomonas aeruginosa, is hindered by a crystalline hemispherical topography with wavelength in the range of 2–8 μm. The motility was determined by the analysis of time-lapse microscopy images of cells in a flowing growth medium maintained at 37 °C. The net displacement of bacteria over 5 min is much lower on surfaces containing 2–8 μm hemispheres than on flat topography, but displacement on the 1 μm hemispheres is not lower. That is, there is a threshold between 1 and 2 μm for response to the topography. Cells on the 4 μm hemispheres were more likely to travel parallel to the local crystal axis than in other directions. Cells on the 8 μm topography were less likely to travel across the crowns of the hemispheres and were also more likely to make 30°–50° turns than on flat surfaces. These results show that surface topography can act as a significant barrier to surface motility and may therefore hinder surface exploration by bacteria. Because surface exploration can be a part of the process whereby bacteria form colonies and seek nutrients, these results help to elucidate the mechanism by which surface topography hinders biofilm formation.  more » « less
Award ID(s):
1609763
PAR ID:
10661339
Author(s) / Creator(s):
 ;  ;  
Publisher / Repository:
ACS
Date Published:
Journal Name:
ACS Applied Materials & Interfaces
Volume:
10
Issue:
11
ISSN:
1944-8244
Page Range / eLocation ID:
9225 to 9234
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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