Title
A Method To Constrain Genome-Scale Models With C-13 Labeling Data
Abstract
Current limitations in quantitatively predicting biological behavior hinder our efforts to engineer biological systems to produce biofuels and other desired chemicals. Here, we present a new method for calculating metabolic fluxes, key targets in metabolic engineering, that incorporates data from C-13 labeling experiments and genome-scale models. The data from C-13 labeling experiments provide strong flux constraints that eliminate the need to assume an evolutionary optimization principle such as the growth rate optimization assumption used in Flux Balance Analysis (FBA). This effective constraining is achieved by making the simple but biologically relevant assumption that flux flows from core to peripheral metabolism and does not flow back. The new method is significantly more robust than FBA with respect to errors in genome-scale model reconstruction. Furthermore, it can provide a comprehensive picture of metabolite balancing and predictions for unmeasured extracellular fluxes as constrained by C-13 labeling data. A comparison shows that the results of this new method are similar to those found through C-13 Metabolic Flux Analysis (C-13 MFA) for central carbon metabolism but, additionally, it provides flux estimates for peripheral metabolism. The extra validation gained by matching 48 relative labeling measurements is used to identify where and why several existing COnstraint Based Reconstruction and Analysis (COBRA) flux prediction algorithms fail. We demonstrate how to use this knowledge to refine these methods and improve their predictive capabilities. This method provides a reliable base upon which to improve the design of biological systems.
Year
DOI
Venue
2015
10.1371/journal.pcbi.1004363
PLOS COMPUTATIONAL BIOLOGY
Keywords
Field
DocType
drug metabolism,optimization,confidence intervals,glucose metabolism
Scale model,Biology,Metabolic flux analysis,Metabolic engineering,Systems biology,Prediction algorithms,Flux,Bioinformatics,Flux balance analysis,Model reconstruction
Journal
Volume
Issue
ISSN
11
9
1553-7358
Citations 
PageRank 
References 
3
0.52
5
Authors
8