Elsevier

Virology

Volume 348, Issue 2, 10 May 2006, Pages 430-436
Virology

The effect of genome length on ejection forces in bacteriophage lambda

https://doi.org/10.1016/j.virol.2006.01.003Get rights and content
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Abstract

A variety of viruses tightly pack their genetic material into protein capsids that are barely large enough to enclose the genome. In particular, in bacteriophages, forces as high as 60 pN are encountered during packaging and ejection, produced by DNA bending elasticity and self-interactions. The high forces are believed to be important for the ejection process, though the extent of their involvement is not yet clear. As a result, there is a need for quantitative models and experiments that reveal the nature of the forces relevant to DNA ejection. Here, we report measurements of the ejection forces for two different mutants of bacteriophage λ, λb221cI26 and λcI60, which differ in genome length by ∼30%. As expected for a force-driven ejection mechanism, the osmotic pressure at which DNA release is completely inhibited varies with the genome length: we find inhibition pressures of 15 atm and 25 atm, for the short and long genomes, respectively, values that are in agreement with our theoretical calculations.

Keywords

Bacteriophage
Lambda
LamB
Maltoporin
Genome delivery
DNA ejection
Pressure

Cited by (0)

1

Present address: Department of Biochemistry, Center for Chemistry and Chemical Engineering, Lund University, Lund, Sweden.

2

Present address: Department of Physics and Astronomy, University of Pennsylvania, PA, USA.