On phage adsorption to bacterial chains

Abstract

Bacteria often arrange themselves in various spatial configurations which changes how they interact with their surroundings. In this paper, we investigate in silico how the structure of the bacterial arrangements influences the adsorption of bacteriophages. We quantify how the adsorption rate scales with the number of bacteria in the arrangement, and show that the adsorption rates for microcolonies (increasing with exponent [~]1/3) and bacterial chains (increasing with exponent [~]0.5 - 0.8) are substantially lower than for well-mixed bacteria (increasing with exponent 1). We further show that, after infection, the spatially clustered arrangements reduce the effective burst size by more than 50 % and cause substantial superinfections in a very short time interval after phage lysis. SIGNIFICANCEWhen bacteria forms clusters they substantially change their exposure to invading phages and other external agents from the well-mixed scenario. Despite this fact, much research has focused on and is focusing on using well-mixed bacteria. Understanding the kinetics of the spatial structures is paramount to developing robust analyses and theories of experimental results. We carefully investigate how the clusters lower the adsorption rate of external phages and how the clustering modifies the hit probabilities for the bacteria.