if model.parameters.get(id='K_m_{}_{}'.format(reaction.id, species.species_type.id)):
                    model_Km = model.parameters.get_one(
                        id='K_m_{}_{}'.format(reaction.id, species.species_type.id))
                    if species.distribution_init_concentration.mean:
                        model_Km.value = beta * species.distribution_init_concentration.mean \