The c4h, tat, hppr and hppd Genes Prompted Engineering of Rosmarinic Acid Biosynthetic Pathway in Salvia miltiorrhiza Hairy Root Cultures

Abstract

Rational engineering to produce biologically active plant compounds has been greatly impeded by our poor understanding of the regulatory and metabolic pathways underlying the biosynthesis of these compounds. Here we capitalized on our previously described gene-to-metabolite network in order to engineer rosmarinic acid (RA) biosynthesis pathway for the production of beneficial RA and lithospermic acid B (LAB) in Salvia miltiorrhiza hairy root cultures. Results showed their production was greatly elevated by (1) overexpression of single gene, including cinnamic acid 4-hydroxylase (c4h), tyrosine aminotransferase (tat), and 4-hydroxyphenylpyruvate reductase (hppr), (2) overexpression of both tat and hppr, and (3) suppression of 4-hydroxyphenylpyruvate dioxygenase (hppd). Co-expression of tat/hppr produced the most abundant RA (906 mg/liter) and LAB (992 mg/liter), which were 4.3 and 3.2-fold more than in their wild-type (wt) counterparts respectively. And the value of RA concentration was also higher than that reported before, that produced by means of nutrient medium optimization or elicitor treatment. It is the first report of boosting RA and LAB biosynthesis through genetic manipulation, providing an effective approach for their large-scale commercial production by using hairy root culture systems as bioreactors.

Diastereomers of lithospermic acid and lithospermic acid B from Monarda fistulosa and Lithospermum erythrorhizon

“…The biosynthetic pathways of LA and LAB are unknown, but it is expected that they are produced from rosmarinic acid [26]. Compound 1 was obtained as the main phenylpropanoid oligomer, and 5 and 6 were not detected in our investigation of M. fistulosa.…”

Bioconversion of stilbenes in genetically engineered root and cell cultures of tobacco

“…In support of this hypothesis, Xiao et al 34. dramatically activated rosmarinic acid biosynthesis by the genetic manipulation of only two genes of the metabolic pathway in hairy root cultures of Salvia miltiorrhiza .…”

Interactions of S-methylmethionine and UV-B can modify the defence mechanisms induced in maize

“…In Salvia miltiorrhiza, the overexpression of C4H activated two parallel pathways of rosmarinic acid biosynthesis, increasing the trans-cinnamic acid and 4-coumaric acid accumulation in the phenylpropanoid pathway and the -tyrosine and 4-hydroxyphenylpyruvic acid in the tyrosine-derived pathway, thus leading to large quantities of the end-products, phenolic acids (Xiao et al 2011 ). Although the expression of C4H was suppressed in all of our treated plants in the first week, significant increase was observed later, most remarkably 14 days after the beginning of UV-B exposure in UV-SMM plants, indicating a strong response of the general phenylpropanoid biosynthetic pathway to the combined effects of UV and SMM.…”