Probabilistic Thermodynamic Analysis of Metabolic Networks.
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ABSTRACT: Motivation
Random sampling of metabolic fluxes can provide a comprehensive description of the capabilities of a metabolic network. However, current sampling approaches do not model thermodynamics explicitly, leading to inaccurate predictions of an organism's potential or actual metabolic operations.Results
We present a probabilistic framework combining thermodynamic quantities with steady-state flux constraints to analyze the properties of a metabolic network. It includes methods for probabilistic metabolic optimization and for joint sampling of thermodynamic and flux spaces. Applied to a model of E. coli, we use the methods to reveal known and novel mechanisms of substrate channeling, and to accurately predict reaction directions and metabolite concentrations. Interestingly, predicted flux distributions are multimodal, leading to discrete hypotheses on E. coli's metabolic capabilities.Availability
Python and MATLAB packages available at https://gitlab.com/csb.ethz/pta.Supplementary information
Supplementary data are available at Bioinformatics online.
SUBMITTER: Gollub MG
PROVIDER: S-EPMC8479673 | biostudies-literature |
REPOSITORIES: biostudies-literature
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