isopropyl-thiogalactoside and naringenin

For production of genistein from N-acetylcysteamine-attached p-coumarate (p-coumaroyl-NAC) supplemented to the medium, a chalcone synthase (CHS) gene from Glycyrrhiza echinata, a chalcone isomerase (CHI) gene from Pueraria lobata, and an isoflavone synthase (IFS) gene from G. echinata were placed under the control of the galactose-inducible GAL promoters in pESC vector and were introduced in Saccharomyces cerevisiae. When the recombinant yeast cells (0.5 g wet weight) were used as "enzyme bags" and incubated at 30 degrees C for 48 h in 100 ml of the buffer containing galactose and 1 mM (265 mg/l) p-coumaroyl-NAC, ca. 340 microg genistein/l was produced. Another system consisting of two enzyme bags was also generated for the purpose of production of genistein from tyrosine. One enzyme bag was an Escherichia coli cell containing a phenylalanine ammonia-lyase gene from a yeast, a 4-coumarate/cinnamate:CoA ligase gene from the actinomycete Streptomyces coelicolor A3(2), the CHS gene, and the CHI gene, in addition to the acetyl-CoA carboxylase gene from Corynebacterium glutamicum, all of which were under the control of the isopropyl-beta-D-thiogalactopyranoside-inducible T7 promoter, and thus producing (S)-naringenin from tyrosine. The other enzyme bag was a S. cerevisiae cell containing the IFS gene. Coincubation of the E. coli cells (0.5 g wet weight) and S. cerevisiae cells (0.5 g wet weight) at 26 degrees C for 60 h in 20 ml of the buffer containing 3 mM (543 mg/l) tyrosine as the starting substrate yielded ca. 6 mg genistein/l.

Topics: Acetyl-CoA Carboxylase; Acyltransferases; Cloning, Molecular; Coenzyme A Ligases; Corynebacterium glutamicum; Coumaric Acids; Escherichia coli; Flavanones; Gene Expression; Genistein; Glycyrrhiza; Intramolecular Lyases; Isopropyl Thiogalactoside; Oxygenases; Phenylalanine Ammonia-Lyase; Promoter Regions, Genetic; Propionates; Pueraria; Saccharomyces cerevisiae; Streptomyces coelicolor; Temperature; Time Factors; Tyrosine