Skip to Main content Skip to Navigation
Journal articles

'Single molecule': theory and experiments, an introduction

Abstract : At scales below micrometers, Brownian motion dictates most of the behaviors. The simple observation of a colloid is striking: a permanent and random motion is seen, whereas inertial forces play a negligible role. This Physics, where velocity is proportional to force, has opened new horizons in biology. The random feature is challenged in living systems where some proteins - molecular motors - have a directed motion whereas their passive behaviors of colloid should lead to a Brownian motion. Individual proteins, polymers of living matter such as DNA, RNA, actin or microtubules, molecular motors, all these objects can be viewed as chains of colloids. They are submitted to shocks from molecules of the solvent. Shapes taken by these biopolymers or dynamics imposed by motors can be measured and modeled from single molecules to their collective effects. Thanks to the development of experimental methods such as optical tweezers, Atomic Force Microscope (AFM), micropipettes, and quantitative fluorescence (such as Förster Resonance Energy Transfer, FRET), it is possible to manipulate these individual biomolecules in an unprecedented manner: experiments allow to probe the validity of models; and a new Physics has thereby emerged with original biological insights. Theories based on statistical mechanics are needed to explain behaviors of these systems. When force-extension curves of these molecules are extracted, the curves need to be fitted with models that predict the deformation of free objects or submitted to a force. When velocity of motors is altered, a quantitative analysis is required to explain the motions of individual molecules under external forces. This lecture will give some elements of introduction to the lectures of the session 'Nanophysics for Molecular Biology'.
Document type :
Journal articles
Complete list of metadatas

Cited literature [10 references]  Display  Hide  Download

https://www.hal.inserm.fr/inserm-00916494
Contributor : Ed. Bmc <>
Submitted on : Tuesday, December 10, 2013 - 1:01:15 PM
Last modification on : Sunday, December 8, 2019 - 11:16:03 AM
Long-term archiving on: : Friday, March 14, 2014 - 9:56:50 AM

Files

Identifiers

  • HAL Id : inserm-00916494, version 1

Collections

Citation

Daniel Riveline. 'Single molecule': theory and experiments, an introduction. Journal of Nanobiotechnology, BioMed Central, 2013, 11 (Suppl 1), pp.S1. ⟨inserm-00916494⟩

Share