DNA packaging and ejection forces in bacteriophage

TitleDNA packaging and ejection forces in bacteriophage
Publication TypeJournal Article
Year of Publication2001
AuthorsJ. T. Kindt, S. Tzlil, A. Ben-Shaul and W. M. Gelbart
Journal TitlePROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
Volume98
Issue24
Pages13671-13674
Date Published2001-11
Type of ArticleJournal Article
KeywordsCONFORMATION, DOUBLE-STRANDED DNA, ESCHERICHIA-COLI, HEADS, lambda, MODEL, ORGANIZATION, STRESS
Abstract

We calculate the forces required to package (or, equivalently, acting to eject) DNA into (from) a bacteriophage capsid, as a function of the loaded (ejected) length, under conditions for which the DNA is either self-repelling or self-attracting. Through computer simulation and analytical theory, we find the loading force to increase more than 10-fold (to tens of piconewtons) during the final third of the loading process, correspondingly, the internal pressure drops 10-fold to a few atmospheres (matching the osmotic pressure in the cell) upon ejection of just a small fraction of the phage genome. We also determine an evolution of the arrangement of packaged DNA from toroidal to spool-like structures.

URLhttp://www.pnas.org/content/98/24/13671.full.pdf