To Stretch the Boundary of Secondary Metabolite Production in Plant Cell‐Based Bioprocessing: Anthocyanin as a Case Study

Abstract

Plant cells and tissue cultures hold great promise for controlled production of a myriad of useful secondary metabolites on demand. The current yield and productivity cannot fulfill the commercial goal of a plant cell-based bioprocess for the production of most secondary metabolites. In order to stretch the boundary, recent advances, new directions and opportunities in plant cell-based bioprocessing have been critically examined for the 10 years from 1992 to 2002. A review of the literature indicated that most of the R&D work was devoted predominantly to studies at an empirical level. A rational approach to molecular plant cell bioprocessing based on the fundamental understanding of metabolic pathways and their regulations is urgently required to stimulate further advances; however, the strategies and technical framework are still being developed. It is the aim of this review to take a step forward in framing workable strategies and technologies for molecular plant cell-based bioprocessing. Using anthocyanin biosynthesis as a case study, an integrated postgenomic approach has been proposed. This combines the functional analysis of metabolic pathways for biosynthesis of a particular metabolite from profiling of gene expression and protein expression to metabolic profiling. A global correlation not only can thus be established at the three molecular levels, but also places emphasis on the interactions between primary metabolism and secondary metabolism; between competing and/or complimentary pathways; and between biosynthetic and post-biosynthetic events.

Expression of an Entire Bacterial Operon in Plants

“…Plants produce a plethora of secondary metabolites that are major ingredients in a wealth of potentially economically valuable substances such as pharmaceuticals, food additives, fragrances, natural pesticides, and more (Morant et al, 2007). However, the production of these metabolites from plants and plant cultures has not yet seen the transition from economic potential to commercial success (Hadacek, 2002;Zhang et al, 2004). Numerous approaches have been attempted to improve the yield of a desired metabolite to a commercially relevant level; metabolic engineering employs genetic engineering techniques to increase production by enhancing gene expression, manipulating a gene's regulatory system (usually transcription factors), preventing branching off to another pathway by down-regulating the competing enzyme, and minimizing catabolism (Verpoorte et al, 1999;Verpoorte and Memelink, 2002).…”

Characterization of anthocyanic vacuolar inclusions in Vitis vinifera L. cell suspension cultures

“…3). They may therefore not be an ideal target for rational enhancement of anthocyanin production as suggested in a number of publications (Taylor 1998;Zhang et al 2002Zhang et al , 2004Gomez et al 2009). …”

Recent advances in plant biotechnology and genetic engineering for production of secondary metabolites

“…Nevertheless the biosynthetic potential of plant cells is considered to be not even half exhausteda total amount of substances produced by plants was estimated in range about 500 thousands [13,14]. Actual models suggest correlation between evolution of secondary metabolism in plants and reciprocal adaptation of pests or pathogens leading to divergence and stimulating biodiversity in the both groups [1].…”

“…In general, three big groups of secondary compounds can be assigned: ter penes, phenolics and alkaloids, which include the main part of currently identified compounds. Their number is estimated to be from more than 50 000 structures to about 100 000 [2,[14][15][16].…”