Fig. 3From: Chromosome engineering of Escherichia coli for constitutive production of salvianic acid AScreening optimal promoter for constitutive expression of hpaBC and d-ldh Y52A for production of SAA. a The hpaBC and d-ldh Y52A were expressed as bicistron under the control of the tac and BBa-J23100 promoters. b hpaBC-d-ldh Y52A was expressed as one operon under the control of the 5tacs and rrnB P1 promoters, respectivelyBack to article page