Constrain-based analysis of gene deletion on the metabolic flux redistribution of Saccharomyces Cerevisiae

Zi-Xiang Xu, Xiao Sun

State Key Laboratory of Bioelectronics, Southeast University.

DOI: 10.4236/jbise.2008.12020                

Abstract

Based on the gene-protein-reaction (GPR) model of S. cerevisiae_iND750 and the method of constraint-based analysis, we first calculated the metabolic flux distribution of S. cere-visiae_iND750. Then we calculated the deletion impact of 438 calculable genes, one by one, on the metabolic flux redistribution of S. cere-visiae_iND750. Next we analyzed the correlation between v (describing deletion impact of one gene) and d (connection degree of one gene) and the correlation between v and Vgene (flux sum controlled by one gene), and found that both of them were not of linear relation. Furthermore, we sought out 38 important genes that most greatly affected the metabolic flux distribution, and determined their functional subsystems. We also found that many of these key genes were related to many but not several subsystems. Because the in silico model of S. cere-visiae_iND750 has been tested by many ex-periments, thus is credible, we can conclude that the result we obtained has biological sig-nificance.

Keywords

Metabonomics, Metabolic engineering, Metabolic networks, Gene deletion, Genome-scale simulation, Flux balance analysis, Gene-protein- reaction (GPR) model, Con-straint-based analysis

Conflicts of Interest

The authors declare no conflicts of interest.

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