| Summary: | Host-parasite interactions are highly susceptible to changes in temperature due to mismatches in
species thermal responses. In nature, parasites often exist in communities, and responses to
temperature are expected to vary between host-parasite pairs. Temperature change thus has
consequences for both host-parasite dynamics and parasite-parasite interactions. Here, we
investigate the impact of warming (37°C, 40°C, 42°C) on parasite life-history traits and competition
using the opportunistic bacterial pathogen Pseudomonas aeruginosa (host) and a panel of three
genetically diverse lytic bacteriophages (parasites). We show that phages vary in their responses to
temperature; while 37°C and 40°C did not have a major effect on phage infectivity, infection by two
phage was restricted at 42°C. This outcome was attributed to disruption of different phage lifehistory traits including host attachment and replication inside hosts. Further, we show that
temperature mediates competition between phages by altering their competitiveness. These results
highlight phage trait variation across thermal regimes with the potential to drive community
dynamics. Our results have important implications for eukaryotic viromes and the design of phage
cocktail therapies.
|
|---|