Physical Intelligence Article 2016

Chemotaxis of bio-hybrid multiple bacteria-driven microswimmers

Physical Intelligence
Guest Researcher
Physical Intelligence
Senior Engineer at Google, San Francisco

In this study, in a bio-hybrid microswimmer system driven by multiple Serratia marcescens bacteria, we quantify the chemotactic drift of a large number of microswimmers towards L-serine and elucidate the associated collective chemotaxis behavior by statistical analysis of over a thousand swimming trajectories of the microswimmers. The results show that the microswimmers have a strong heading preference for moving up the L-serine gradient, while their speed does not change considerably when moving up and down the gradient; therefore, the heading bias constitutes the major factor that produces the chemotactic drift. The heading direction of a microswimmer is found to be significantly more persistent when it moves up the L-serine gradient than when it travels down the gradient; this effect causes the apparent heading preference of the microswimmers and is the crucial reason that enables the seemingly cooperative chemotaxis of multiple bacteria on a microswimmer. In addition, we find that their chemotactic drift velocity increases superquadratically with their mean swimming speed, suggesting that chemotaxis of bio-hybrid microsystems can be enhanced by designing and building faster microswimmers. Such bio-hybrid microswimmers with chemotactic steering capability may find future applications in targeted drug delivery, bioengineering, and lab-on-a-chip devices.

Author(s): Zhuang, Jiang and Sitti, Metin
Journal: Scientific reports
Volume: 6
Number (issue): 1
Pages: 1--10
Year: 2016
Month: March
Project(s):
BibTeX Type: Article (article)
DOI: 10.1038/srep32135
Electronic Archiving: grant_archive

BibTeX

@article{zhuang2016chemotaxis,
  title = {Chemotaxis of bio-hybrid multiple bacteria-driven microswimmers},
  journal = {Scientific reports},
  abstract = {In this study, in a bio-hybrid microswimmer system driven by multiple Serratia marcescens bacteria, we quantify the chemotactic drift of a large number of microswimmers towards L-serine and elucidate the associated collective chemotaxis behavior by statistical analysis of over a thousand swimming trajectories of the microswimmers. The results show that the microswimmers have a strong heading preference for moving up the L-serine gradient, while their speed does not change considerably when moving up and down the gradient; therefore, the heading bias constitutes the major factor that produces the chemotactic drift. The heading direction of a microswimmer is found to be significantly more persistent when it moves up the L-serine gradient than when it travels down the gradient; this effect causes the apparent heading preference of the microswimmers and is the crucial reason that enables the seemingly cooperative chemotaxis of multiple bacteria on a microswimmer. In addition, we find that their chemotactic drift velocity increases superquadratically with their mean swimming speed, suggesting that chemotaxis of bio-hybrid microsystems can be enhanced by designing and building faster microswimmers. Such bio-hybrid microswimmers with chemotactic steering capability may find future applications in targeted drug delivery, bioengineering, and lab-on-a-chip devices.},
  volume = {6},
  number = {1},
  pages = {1--10},
  month = mar,
  year = {2016},
  author = {Zhuang, Jiang and Sitti, Metin},
  doi = {10.1038/srep32135},
  month_numeric = {3}
}