Abstract:
:Many biological processes exhibit complex kinetic behavior that involves a nontrivial distribution of rate constants. Characterization of the rate constant distribution is often critical for mechanistic understandings of these processes. However, it is difficult to extract a rate constant distribution from data measured in the time domain. This is due to the numerical instability of the inverse Laplace transform, a long-standing mathematical challenge that has hampered data analysis in many disciplines. Here, we present a method that allows us to reconstruct the probability distribution of rate constants from decay data in the time domain, without fitting to specific trial functions or requiring any prior knowledge of the rate distribution. The robustness (numerical stability) of this reconstruction method is numerically illustrated by analyzing data with realistic noise and theoretically proved by the continuity of the transformations connecting the relevant function spaces. This development enhances our ability to characterize kinetics and dynamics of biological processes. We expect this method to be useful in a broad range of disciplines considering the prevalence of complex exponential decays in many experimental systems.
journal_name
Biophys Jjournal_title
Biophysical journalauthors
Zhou Y,Zhuang Xdoi
10.1529/biophysj.106.090688subject
Has Abstractpub_date
2006-12-01 00:00:00pages
4045-53issue
11eissn
0006-3495issn
1542-0086pii
S0006-3495(06)72120-8journal_volume
91pub_type
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