Construction of the Bacterial Cellulose Biosynthesis Network and Metabolic Flux Analysis

The metabolic network of Acetobacter xylinum for bacterial cellulose(abbr.BC)biosynthesis was constructed.Based on the metabolic flux balance model,the metabolic flux distribution of BC synthesis was calculated by material balances and linear programming(Lingo).The results of metabolic flux analysis indicate that the glucose enters PPP and TCA cycle.In fermentation earlier stage,the biomass are synthesized and BC has a high yield;while in the later stage,a quantity of futile cycles appears and BC yield decreases.The metabolic fluxes entering the by-product and futile cycle result in the waste of carbon source.Therefore,it is necessary to use the genetic manipulation,mutation or change fermentation condition to reduce the by-product formation and improve BC yield.