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Forces Controlling the Rate of DNA Ejection from Page λ

Löf, David LU ; Schillén, Karin LU ; Jönsson, Bengt LU and Evilevitch, Alex LU (2007) In Journal of Molecular Biology 368(1). p.55-65
Abstract
The goal of this work was to investigate how internal and external forces acting on DNA affect the rate of genome ejection from bacteriophage λ after the ejection is triggered in vitro by a λ receptor. The rate of ejection was measured with time-resolved static and dynamic light scattering, while varying such parameters as temperature and packaged DNA length, as well as adding DNA-binding proteins to the host solution. We found that temperature has a strong effect on the ejection rate, with an exponential increase of the initial ejection rate as a function of temperature. This can possibly be explained by the temperature-induced conformational changes in the tail pore-forming proteins where the “open” conformation dominates over “closed”,... (More)
The goal of this work was to investigate how internal and external forces acting on DNA affect the rate of genome ejection from bacteriophage λ after the ejection is triggered in vitro by a λ receptor. The rate of ejection was measured with time-resolved static and dynamic light scattering, while varying such parameters as temperature and packaged DNA length, as well as adding DNA-binding proteins to the host solution. We found that temperature has a strong effect on the ejection rate, with an exponential increase of the initial ejection rate as a function of temperature. This can possibly be explained by the temperature-induced conformational changes in the tail pore-forming proteins where the “open” conformation dominates over “closed”, at elevated temperatures. The DNA length also had an effect on initial ejection rate, with a nearly linear dependence comparing the three different genomes (37.7, 45.7 and 48.5 kb DNA), with faster ejection rate for longer genomes. Since the initial rate of ejection increases in an almost direct relationship with the length of the genome, the total time needed to eject DNA completely appeared to be nearly constant for all three DNA length phage mutants. The increased initial rate of ejection with increasing DNA length is due to the increased DNA bending and inter-strand repulsion forces for the longer DNA chains. Finally, we also show that addition of non-specific DNA-binding proteins (HU and DNase I) increases the rate of ejection by exerting additional “pulling” forces on the DNA that is being ejected. (Less)
Please use this url to cite or link to this publication:
author
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
DNA ejection kinetics, HU, DNA pressure, phage ejection, light scattering
in
Journal of Molecular Biology
volume
368
issue
1
pages
55 - 65
publisher
Elsevier
external identifiers
  • wos:000245672500006
  • scopus:33947325925
ISSN
1089-8638
DOI
10.1016/j.jmb.2007.01.076
language
English
LU publication?
yes
id
620e22ff-813c-46a2-9fcf-5c1e64452a52 (old id 642327)
date added to LUP
2007-12-04 16:04:46
date last changed
2017-11-19 03:26:16
@article{620e22ff-813c-46a2-9fcf-5c1e64452a52,
  abstract     = {The goal of this work was to investigate how internal and external forces acting on DNA affect the rate of genome ejection from bacteriophage λ after the ejection is triggered in vitro by a λ receptor. The rate of ejection was measured with time-resolved static and dynamic light scattering, while varying such parameters as temperature and packaged DNA length, as well as adding DNA-binding proteins to the host solution. We found that temperature has a strong effect on the ejection rate, with an exponential increase of the initial ejection rate as a function of temperature. This can possibly be explained by the temperature-induced conformational changes in the tail pore-forming proteins where the “open” conformation dominates over “closed”, at elevated temperatures. The DNA length also had an effect on initial ejection rate, with a nearly linear dependence comparing the three different genomes (37.7, 45.7 and 48.5 kb DNA), with faster ejection rate for longer genomes. Since the initial rate of ejection increases in an almost direct relationship with the length of the genome, the total time needed to eject DNA completely appeared to be nearly constant for all three DNA length phage mutants. The increased initial rate of ejection with increasing DNA length is due to the increased DNA bending and inter-strand repulsion forces for the longer DNA chains. Finally, we also show that addition of non-specific DNA-binding proteins (HU and DNase I) increases the rate of ejection by exerting additional “pulling” forces on the DNA that is being ejected.},
  author       = {Löf, David and Schillén, Karin and Jönsson, Bengt and Evilevitch, Alex},
  issn         = {1089-8638},
  keyword      = {DNA ejection kinetics,HU,DNA pressure,phage ejection,light scattering},
  language     = {eng},
  number       = {1},
  pages        = {55--65},
  publisher    = {Elsevier},
  series       = {Journal of Molecular Biology},
  title        = {Forces Controlling the Rate of DNA Ejection from Page λ},
  url          = {http://dx.doi.org/10.1016/j.jmb.2007.01.076},
  volume       = {368},
  year         = {2007},
}