Studies of sector formation in expanding bacterial colonies

School of Physics and Astronomy, Raymond and Beverly Sackler Faculty of Exact Sciences, Tel Aviv University, Tel Aviv 69 978, Israel

Received: 26 May 1999
Accepted: 1 October 1999

Abstract

We study sector formation in expanding bacterial colonies grown on a substrate with low level of nutrient. Bursts of sectors are observed both during compact growth on soft agar and during branching growth on semi-solid agar. For theoretical studies of these bursts we employ two mathematical models we have used successfully in the past to study patterning of bacterial colonies: a discrete model and a continuous reaction-diffusion model. Using these models we investigate the amount of segregation achieved by a neutral mutation, as well as by mutations having some advantage over the wild type. We also study the effect of chemotaxis signaling on the sector formation.