Biology – Quantitative Biology – Molecular Networks
Scientific paper
2009-05-17
Biology
Quantitative Biology
Molecular Networks
11 pages, 6 figures, to appear in Systems and Synthetic Biology
Scientific paper
Constraint-based flux balance analysis (FBA) has proven successful in predicting the flux distribution of metabolic networks in diverse environmental conditions. FBA finds one of the alternate optimal solutions that maximizes the biomass production rate. Almaas et al have shown that the flux distribution follows a power law, and it is possible to associate with most metabolites two reactions which maximally produce and consume a give metabolite, respectively. This observation led to the concept of high-flux backbone (HFB) in metabolic networks. In previous work, the HFB has been computed using a particular optima obtained using FBA. In this paper, we investigate the conservation of HFB of a particular solution for a given medium across different alternate optima and near-optima in metabolic networks of E. coli and S. cerevisiae. Using flux variability analysis (FVA), we propose a method to determine reactions that are guaranteed to be in HFB regardless of alternate solutions. We find that the HFB of a particular optima is largely conserved across alternate optima in E. coli, while it is only moderately conserved in S. cerevisiae. However, the HFB of a particular near-optima shows a large variation across alternate near-optima in both organisms. We show that the conserved set of reactions in HFB across alternate near-optima has a large overlap with essential reactions and reactions which are both uniquely consuming (UC) and uniquely producing (UP). Our findings suggest that the structure of the metabolic network admits a high degree of redundancy and plasticity in near-optimal flow patterns enhancing system robustness for a given environmental condition.
No associations
LandOfFree
Conservation of high-flux backbone in alternate optimal and near-optimal flux distributions of metabolic networks does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Conservation of high-flux backbone in alternate optimal and near-optimal flux distributions of metabolic networks, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Conservation of high-flux backbone in alternate optimal and near-optimal flux distributions of metabolic networks will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-514133