We set the objective function of the constructed models to the given reactions (acetyl-CoA synthetase and acetyl-CoA carboxylase reactions) and turned the lower bound to zero for maximizing the production and regulation reaction of acetyl-CoA.

The producing reaction of acetyl-CoA is catalyzed by acetyl-CoA synthetase, which is in turn regulated by acetyl-CoA carboxylase, an enzyme which catalyzes acetyl CoA conversion to malonyl-CoA, the first and rate-limiting reaction in de novo synthesis of fatty acids. The optimal objective values for acetyl-CoA regulation and production calculated by FBA for all models. Models 1–9 refer to the H3 deleted tail model, the H3 substituted tail model, the H4 substituted tail model, the H4 deleted tail model, the H2B deleted tail model, the H2B substituted tail model, the H2A deleted tail model, the H2A substituted tail model and the H3 depletion model, respectively.We set the objective function of the constructed models to the given reactions (acetyl-CoA synthetase and acetyl-CoA carboxylase reactions) and turned the lower bound to zero for maximizing the production and regulation reaction of acetyl-CoA.