Starts 29 Apr 2008 13:30
Ends 29 Apr 2008 20:00
Central European Time
SISSA Main Bldg.-Lecture Room 'D'
In recent years we have assisted to a big breakthrough in system biology, the interdisciplinary field that studies the biological problems going beyond the single biomolecular framework with the description of the intertwined reactions between the constituent of the cell in terms of networks. In this talk we study the problem of flux distribution in metabolic networks by statistical mechanics methods. We will first derive the most probable flux distribution with intermediate metabolites at steady state secondly we will study the flux distribution close to optimal biomass production. Analytical tractability of the models is possible if the problems are defined over random graphs with the same degree distribution of the real metabolic networks. The flux distribution close to the optimal biomass production develops a fat tail with power-law exponent independent on the structure of the underline network in perfect agreement with bioinfoarmatics methods and in qualitative agreement with experiments. To solve these problems we will introduce a Gaussian Replica Symmetric Ansatz valid for quadratic models defined on continuous variables refined on the real axis, and a new method for study cavity equations on continuous variables close to a critical point.
  • M. Poropat