TitleLimits of sensing temporal concentration changes by single cells.
Publication TypeJournal Article
Year of Publication2010
AuthorsMora, T, Wingreen, NS
JournalPhys Rev Lett
Volume104
Issue24
Pagination248101
Date Published2010 Jun 18
KeywordsAlgorithms, Bacteria, Chemotaxis, Models, Biological, Receptors, Cell Surface, Single-Cell Analysis
Abstract

Berg and Purcell [Biophys. J. 20, 193 (1977)] calculated how the accuracy of concentration sensing by single-celled organisms is limited by noise from the small number of counted molecules. Here we generalize their results to the sensing of concentration ramps, which is often the biologically relevant situation (e.g., during bacterial chemotaxis). We calculate lower bounds on the uncertainty of ramp sensing by three measurement devices: a single receptor, an absorbing sphere, and a monitoring sphere. We contrast two strategies, simple linear regression of the input signal versus maximum likelihood estimation, and show that the latter can be twice as accurate as the former. Finally, we consider biological implementations of these two strategies, and identify possible signatures that maximum likelihood estimation is implemented by real biological systems.

Alternate JournalPhys. Rev. Lett.