Characterizing phenotypic plasticity: a phase plane analysis

Flux-balance analysis (FBA) was used to map the optimal metabolic phenotypes expressed by a genotype, under different environments. A finite number of optimal phenotypes were found and they were confined to specific regions in a plane formed by the values of two environmental variables, represented as uptake rates. The analysis was performed for growth on two different carbon sources (acetate and glucose) at various levels of oxygenation. It was determined, that there are a number of distinct optimal metabolic phenotypes expressed under varying carbon-oxygen limitations. These in silico results lead to a mechanistic interpretation of environmental factors on the complex genotype-phenotype relation and characterize the phenotypic plasticity of the organism