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Title: Self-propelling and rolling of a sessile-motile aggregate of the bacterium Caulobacter crescentus
Abstract Active dispersal of microorganisms is often attributed to the cells’ motile organelles. However, much less is known about whether sessile cells can access such motility through aggregation with motile counterparts. Here, we show that the rosette aggregates of the bacteriumCaulobacter crescentus, although predominantly sessile, can actively disperse through the flagellar motors of motile members. Comparisons in kinematics between the motile rosettes and solitary swimming cells indicate that the rosettes can be powered by as few as a single motor. We further reconstructed the 3D movements of the rosettes to reveal that their proximity to a solid-liquid interface promotes a wheel-like rolling, as powered by the flagellar torque. This rolling movement also features a sequence of sharp turns, a reorientation mechanism distinct from that of swimming cells. Overall, our study elucidates an unexplored regime of aggregation-based motility that can be widely applied to sessile-motile composites.  more » « less
Award ID(s):
1706511
PAR ID:
10226174
Author(s) / Creator(s):
;
Publisher / Repository:
Nature Publishing Group
Date Published:
Journal Name:
Communications Biology
Volume:
3
Issue:
1
ISSN:
2399-3642
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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