Switch to
| Predicate | Object |
|---|---|
| rdf:type | |
| lifeskim:mentions | |
| pubmed:issue |
4
|
| pubmed:dateCreated |
1998-11-25
|
| pubmed:abstractText |
Macromolecular binding forces between single protein-ligand pairs have been directly measured with the Atomic Force Microscope (AFM) in several recent experiments. In a typical measurement, the AFM probe, or cantilever, is attached to the ligand and exerts a disruptive force on the bond between the macromolecular pair while the receptor is held fixed; the probe is then moved away from the substrate until the bond is broken. When the bond actually breaks, the tip is observed to slip; in fact, the ligand is jumping to a new equilibrium point determined purely by the cantilever, as if the receptor had been instantaneously moved to infinity. This "jumping-off" or "minimum rupture force" is determined by measuring cantilever deflection. In a similar manner, the two molecules can be brought together and the "jumping-on" force can be determined. These two measurements will result in different estimates of the binding force due to hysteresis. This hysteresis is caused by a cusp catastrophe in the space defined by probe position and cantilever stiffness. The phenomena of "jumping-off" in macromolecular rupture experiments and "jumping-on" when molecules are brought together occur when the system passes through a saddle-node bifurcation as the probe position is varied. Probe approach and withdrawal result in different post-bifurcation equilibria, different energy dissipation, and different force measurements.
|
| pubmed:language |
eng
|
| pubmed:journal | |
| pubmed:citationSubset |
IM
|
| pubmed:chemical | |
| pubmed:status |
MEDLINE
|
| pubmed:month |
Oct
|
| pubmed:issn |
0022-5193
|
| pubmed:author | |
| pubmed:copyrightInfo |
Copyright 1998 Academic Press
|
| pubmed:issnType |
Print
|
| pubmed:day |
21
|
| pubmed:volume |
194
|
| pubmed:owner |
NLM
|
| pubmed:authorsComplete |
Y
|
| pubmed:pagination |
551-9
|
| pubmed:dateRevised |
2004-11-17
|
| pubmed:meshHeading |
pubmed-meshheading:9790829-Animals,
pubmed-meshheading:9790829-Biomechanics,
pubmed-meshheading:9790829-Macromolecular Substances,
pubmed-meshheading:9790829-Microscopy, Atomic Force,
pubmed-meshheading:9790829-Models, Biological,
pubmed-meshheading:9790829-Nonlinear Dynamics,
pubmed-meshheading:9790829-Protein Binding,
pubmed-meshheading:9790829-Proteins
|
| pubmed:year |
1998
|
| pubmed:articleTitle |
Hysteresis in force probe measurements: a dynamical systems perspective.
|
| pubmed:affiliation |
Department of Biomathematics, UCLA School of Medicine, AV-155 CHS, 10833 Le Conte Ave, Los Angeles, CA, 90095-1766, USA. bshapiro@ucla.edu
|
| pubmed:publicationType |
Journal Article
|