Competitive Fitness in Coronaviruses Is Not Correlated with Size or Number of Double-Membrane Vesicles under Reduced-Temperature Growth Conditions

Al-Mulla, Hawaa M. N.; Turrell, Lauren; Smith, Nicola M.; Payne, Luke; Baliji, Surendranath; Züst, Roland; Thiel, Volker; Baker, Susan C.; Siddell, Stuart G.; Neuman, Benjamin W.

Brts105 and Wüts18 showed a small but statistically significant increase in fitness compared to the wild type, Brts31 and Albts16 did not differ significantly in fitness from the wild type, and Albts22 appeared somewhat but not significantly less fit than the wild type in continuous cells (Fig. 5B) . Results from primary MEFs agreed with continuous-cell results. This also showed that Brts105 and Wüts18 are cold adapted compared to wild-type virus, in addition to being ts. This demonstrated that viruses that produce larger replicative organelles (Fig. 5) (Albts16, Wüts18, and Brts31 versus the wild type) or more numerous replicative organelles (Fig. 5 ) (Brts31 and Brts105 versus the wild type) do not have a competitive disadvantage per se under these assay conditions.