Swarming Ring Patterns in Bacterial Colonies Exposed to Ultraviolet Radiation

Phys. Rev. Lett. 87, 158102 – Published 21 September 2001
Anna M. Delprato, Azadeh Samadani, A. Kudrolli, and L. S. Tsimring


We report a novel morphological transition in a Bacillus subtilis colony initially growing under ambient conditions, after ultraviolet radiation exposure. The bacteria in the central regions of the colonies are observed to migrate towards the colony edge forming a ring during uniform spatial exposure. When the radiation is switched off, the colonies were observed to grow both inward into the evacuated regions as well as outward indicating that the pattern is not formed due to depletion of nutrients at the center of the colony. We also propose a reaction-diffusion model in which waste-limited chemotaxis initiated by the UV radiation leads to the observed phenomenology.

DOI: http://dx.doi.org/10.1103/PhysRevLett.87.158102

  • Received 7 May 2001
  • Published 21 September 2001

© 2001 The American Physical Society

Authors & Affiliations

Anna M. Delprato1,2, Azadeh Samadani1, A. Kudrolli1,*, and L. S. Tsimring3

  • 1Department of Physics, Clark University, Worcester, Massachusetts 01610
  • 2Department of Biology, Clark University, Worcester, Massachusetts 01610
  • 3Institute for Nonlinear Science, University of California, San Diego, California 92093-0402

  • *Corresponding author.

References (Subscription Required)

Authorization Required


Download & Share

PDF Export Citing Articles (8)



Log In



Article Lookup
Paste a citation or DOI

Enter a citation
  1. Enter a citation to look up or terms to search.

    Ex: "PRL 112 068103", "Phys. Rev. Lett. 112, 068103", "10.1103/PhysRevLett.112.068103"