|Title||DNA packaging and ejection forces in bacteriophage|
|Publication Type||Journal Article|
|Year of Publication||2001|
|Authors||J. T. Kindt, S. Tzlil, A. Ben-Shaul and W. M. Gelbart|
|Journal Title||PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA|
|Type of Article||Journal Article|
|Keywords||CONFORMATION, DOUBLE-STRANDED DNA, ESCHERICHIA-COLI, HEADS, lambda, MODEL, ORGANIZATION, STRESS|
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.