Fig. 3.
A salinity threshold is needed for ICP1 predation. Some 107 CFU of V. cholerae from an overnight culture were preadapted overnight in 0.7% Instant Ocean, fresh water, or fresh water supplemented with NaCl (0.09 or 0.17 M) in the absence of an added carbon source. ICP1 was added to a MOI of 0.01 to assess bacterial viability and phage replication over time. Shown is the average with a standard error (SE) of, at least, six biological replicates. (A) Bacterial viability at 7 h. (B) The ratio of phages in the culture supernatant at 7 h relative to the number initially added. (C) Bacterial viability at 7 h (*P < 0.05, **P < 0.005, ****P < 0.0001). FW, fresh water; ns, not significant; PFU, plaque-forming units.