Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2000 Jun;17(6):942-50.
doi: 10.1093/oxfordjournals.molbev.a026375.

Big-benefit mutations in a bacteriophage inhibited with heat

J J Bull  1 , M R Badgett, H A Wichman
Affiliations

Big-benefit mutations in a bacteriophage inhibited with heat

J J Bull et al. Mol Biol Evol. 2000 Jun.

Abstract

High temperature inhibits the growth of the wild-type bacteriophage phiX174. Three different point mutations were identified that each recovered growth at high temperature. Two affected the major capsid protein (residues F188 and F242), and one affected the internal scaffolding protein (B114). One of the major capsid mutations (F242) is located in a beta strand that contacts B114 in the procapsid during viral maturation, whereas the other capsid mutation (F188) is involved in subunit interactions at the threefold axis of symmetry. Selective coefficients of these mutations ranged from 13.9 to 3.8 in the inhibitory, hot environment, but all mutations reduced fitness at normal temperature. The selective effect of one of the mutations (F242) was evaluated at high temperature in four different genetic backgrounds and exhibited epistasis of diminishing returns: as log fitness of the background genotype increased from -0.1 to 4.1, the fitness boost provided by the F242 mutation decreased from 3.9 to 0. 8. These results support a model in which viral fitness is bounded by an upper limit and the benefit of a mutation is scaled according to the remaining opportunity for fitness improvement in the genome.

PubMed Disclaimer

Similar articles

See all similar articles

Cited by

See all "Cited by" articles

Publication types

LinkOut - more resources