Fitness benefits of low infectivity in a spatially structured population of bacteriophages
Authored by Stephen M Krone, Pavitra Roychoudhury, Neelima Shrestha, Valorie R Wiss
Date Published: 2014
DOI: 10.1098/rspb.2013.2563
Sponsors:
United States National Institutes of Health (NIH)
National Center for Research Resources (NCRR)
Platforms:
No platforms listed
Model Documentation:
Other Narrative
Mathematical description
Model Code URLs:
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Abstract
For a parasite evolving in a spatially structured environment, an
evolutionarily advantageous strategy may be to reduce its transmission
rate or infectivity. We demonstrate this empirically using bacteriophage
(phage) from an evolution experiment where spatial structure was
maintained over 550 phage generations on agar plates. We found that a
single substitution in the major capsid protein led to slower adsorption
of phage to host cells with no change in lysis time or burst size.
Plaques formed by phage isolates containing this mutation were not only
larger but also contained more phage per unit area. Using a spatially
explicit, individual-based model, we showed that when there is a
trade-off between adsorption and diffusion (i.e. less `sticky' phage
diffuse further), slow adsorption can maximize plaque size, plaque
density and overall productivity. These findings suggest that less
infective pathogens may have an advantage in spatially structured
populations, even when well-mixed models predict that they will not.
Tags
environment
invasion
Pathogen
Life-history
Optimality
Experimental evolution
Viral adaptation
Lysis
Phi-x174
Plaque