Genetic engineering approach using early Vinca alkaloid biosynthesis genes led to increased tryptamine and terpenoid indole alkaloids biosynthesis in differentiating cultures of Catharanthus roseus

Abstract

Catharanthus roseus today occupies the central position in ongoing metabolic engineering efforts in medicinal plants. The entire multi-step biogenetic pathway of its very expensive anticancerous alkaloids vinblastine and vincristine is fairly very well dissected at biochemical and gene levels except the pathway steps leading to biosynthesis of monomeric alkaloid catharanthine and tabersonine. In order to enhance the plant-based productivity of these pharma molecules for the drug industry, cell and tissue cultures of C. roseus are being increasingly tested to provide their alternate production platforms. However, a rigid developmental regulation and involvement of different cell, tissues, and organelles in the synthesis of these alkaloids have restricted the utility of these cultures. Therefore, the present study was carried out with pushing the terpenoid indole alkaloid pathway metabolic flux towards dimeric alkaloids vinblastine and vincristine production by over-expressing the two upstream pathway genes tryptophan decarboxylase and strictosidine synthase at two different levels of cellular organization viz. callus and leaf tissues. The transformation experiments were carried out using Agrobacterium tumefaciens LBA1119 strain having tryptophan decarboxylase and strictosidine synthase gene cassette. The callus transformation reported a maximum of 0.027% dry wt vindoline and 0.053% dry wt catharanthine production, whereas, the transiently transformed leaves reported a maximum of 0.30% dry wt vindoline, 0.10% catharanthine, and 0.0027% dry wt vinblastine content.

AtMYB12-Expressing Transgenic Tobacco Increases Resistance to Several Phytopathogens and Aphids

“…The accumulation of certain secondary metabolic components, such as flavonoids, has been demonstrated to enhance insect resistance to plants (Thoison et al, 2004;Sharma et al, 2018). The transgenic lines of AtMYB12 tobacco have greater significant resistance to insects compared with the control, with more than 70% mortality for S. litura and H. armigera (Misra et al, 2010).…”

From Ethnomedicine to Plant Biotechnology and Machine Learning: The Valorization of the Medicinal Plant Bryophyllum sp.

“…In our opinion, the current trends and future challenges on the research of non-well characterized medicinal plants are: (i) the combination of plant in vitro systems, using molecular approaches, and nutritional studies [128], with the purpose of characterizing their full biosynthetic potential; (ii) the enhancement of secondary metabolism throughout the application of metabolic engineering, as it has been performed in the cases of trans-resveratrol [168] and terpenoid indole alkaloids [169]; (iii) the application of high throughput technologies, such as metabolomics, for the characterization of metabolic fingerprinting associated to elicitation of PSCCs, in response to plant stress, at a biochemical and biosynthetic level [170,171]. Finally, the combination of PTC and ML with omics technologies will assist to the establishment of new perspectives on the field of phytochemistry and the study of the biosynthetic potential of unexplored plants, as it is the case of Bryophyllum.…”

Plant regeneration and transformation of Trachyspermum ammi using Agrobacterium tumefaciens and zygotic embryos

“…The results showed enhancement thymol level in both wild type and transformed plants of ajowan (39.2 and 55.07%) by the drought stress [ 57 ]. In another study conducted by Sharma et al [ 58 ], it was found that overexpression of Tryptophan decarboxylase and strictosidine synthase in Catharanthus roseus increased vindoline, catharanthine, and vinblastine content.…”