Advanced

Physical Properties of Escherichia coli P Pili Measured by Optical Tweezers

Jass, Jana; Schedin, Staffan; Fällman, Erik; Ohlsson, Jörgen LU ; Nilsson, Ulf LU ; Uhlin, Bernt Eric and Axner, Ove (2004) In Biophysical Journal 87(6). p.4271-4283
Abstract
The mechanical behavior of individual P pili of uropathogenic Escherichia coli has been investigated using optical tweezers. P pili, whose main part constitutes the PapA rod, composed of 103 PapA subunits in a helical arrangement, are distributed over the bacterial surface and mediate adhesion to host cells. They are particularly important in the pathogenesis of E. coli colonizing the upper urinary tract and kidneys. A biological model system has been established for in situ measurements of the forces that occur during mechanical stretching of pili. A mathematical model of the force-versus-elongation behavior of an individual pilus has been developed. Three elongation regions of pili were identified. In region I, P pili stretch... (More)
The mechanical behavior of individual P pili of uropathogenic Escherichia coli has been investigated using optical tweezers. P pili, whose main part constitutes the PapA rod, composed of 103 PapA subunits in a helical arrangement, are distributed over the bacterial surface and mediate adhesion to host cells. They are particularly important in the pathogenesis of E. coli colonizing the upper urinary tract and kidneys. A biological model system has been established for in situ measurements of the forces that occur during mechanical stretching of pili. A mathematical model of the force-versus-elongation behavior of an individual pilus has been developed. Three elongation regions of pili were identified. In region I, P pili stretch elastically, up to a relative elongation of 16 ± 3%. The product of elasticity modulus and area of a P pilus, EA, was assessed to 154 ± 20 pN (n = 6). In region II, the quaternary structure of the PapA rod unfolds under a constant force of 27 ± 2 pN (n 100) by a sequential breaking of the interactions between adjacent layers of PapA subunits. This unfolding can elongate the pilus up to 7 ± 2 times. In region III, pili elongate in a nonlinear manner as a result of stretching until the bond ruptures. (Less)
Please use this url to cite or link to this publication:
author
organization
publishing date
type
Contribution to journal
publication status
published
subject
in
Biophysical Journal
volume
87
issue
6
pages
4271 - 4283
publisher
Cell Press
external identifiers
  • wos:000225426700061
  • pmid:15377509
  • scopus:10044230753
ISSN
1542-0086
DOI
10.1529/biophysj.104.044867
language
English
LU publication?
yes
id
c2c5b5f5-3570-4569-8f87-a131c318edb7 (old id 141533)
date added to LUP
2007-07-10 11:26:18
date last changed
2017-08-27 04:17:43
@article{c2c5b5f5-3570-4569-8f87-a131c318edb7,
  abstract     = {The mechanical behavior of individual P pili of uropathogenic Escherichia coli has been investigated using optical tweezers. P pili, whose main part constitutes the PapA rod, composed of 103 PapA subunits in a helical arrangement, are distributed over the bacterial surface and mediate adhesion to host cells. They are particularly important in the pathogenesis of E. coli colonizing the upper urinary tract and kidneys. A biological model system has been established for in situ measurements of the forces that occur during mechanical stretching of pili. A mathematical model of the force-versus-elongation behavior of an individual pilus has been developed. Three elongation regions of pili were identified. In region I, P pili stretch elastically, up to a relative elongation of 16 ± 3%. The product of elasticity modulus and area of a P pilus, EA, was assessed to 154 ± 20 pN (n = 6). In region II, the quaternary structure of the PapA rod unfolds under a constant force of 27 ± 2 pN (n 100) by a sequential breaking of the interactions between adjacent layers of PapA subunits. This unfolding can elongate the pilus up to 7 ± 2 times. In region III, pili elongate in a nonlinear manner as a result of stretching until the bond ruptures.},
  author       = {Jass, Jana and Schedin, Staffan and Fällman, Erik and Ohlsson, Jörgen and Nilsson, Ulf and Uhlin, Bernt Eric and Axner, Ove},
  issn         = {1542-0086},
  language     = {eng},
  number       = {6},
  pages        = {4271--4283},
  publisher    = {Cell Press},
  series       = {Biophysical Journal},
  title        = {Physical Properties of Escherichia coli P Pili Measured by Optical Tweezers},
  url          = {http://dx.doi.org/10.1529/biophysj.104.044867},
  volume       = {87},
  year         = {2004},
}