The findings, published in Nature Communications, reveal a way to produce industrial quantities of potentially beneficial natural compounds efficiently – by growing them in genetically modified tomatoes.
Led by Dr Yang Zhang and Dr Eugenio Butelli at the John Innes Centre in the UK, the research team tested the effect of introducing a protein called AtMYB12 – which activates a set of genes involved in the production of producing natural compounds – and genes encoding enzymes specific for making resveratrol and in to tomatoes.
According to the team, the AtMYB12 protein acts a bit like a tap to increase or reduce the production of natural compounds depending on how much of the protein is present.
Zhang and Butelli revealed that the genetic modifications acted to both increase the capacity of the plant to produce natural compounds (by activating phenylpropanoid production) and to influence the amount of energy and carbon the plant dedicated to producing these natural compounds.
Indeed, introduction of the AtMYB12 protein meant tomato plants began to create more beneficial compounds including resveratrol and genistein, and devoted more of energy to doing this.
“Our research provides a fantastic platform to quickly produce these valuable medicinal compounds in tomatoes,” said Zhang – who noted that target compounds could be purified directly from tomato juice.
Indeed, the authors noted that the study resulted in tomatoes that could produce as much as 80mg of novel compounds per gram of dry weight - demonstrating that industrial scale up is possible.
"Our study provides a general tool for producing valuable phenylpropanoid compounds on an industrial scale in plants, and potentially production of other products derived from aromatic amino acids,” commented senior author Professor Cathie Martin – who added that the work will be of interest to people performing fundamental research on plants, plant/microbe engineering, medicinal plant natural products, “as well as diet and health research."
“We believe our design idea could also be applied to other compounds such as terpenoids and alkaloids, which are the major groups of medicinal compounds from plants,” said Zhang.
Industrial scale
The team noted that because tomatoes are a high yielding crop – producing up to 500 tonnes per hectare in countries delivering the highest yields – and require relatively few inputs, the production of valuable compounds like resveratrol or genistein in tomatoes could be economical compared to relying on artificial synthesis in a lab or extracting them in tiny quantities from traditional plant sources like grapes and soybeans.
They noted that the tomatoes can be harvested and juiced and the valuable compounds can be extracted from the juice and that the tomatoes themselves could potentially become the source of increased nutritional value.
Source: Nature Communications
Volume 6, Article number: 8635, Open Access, doi: 10.1038/ncomms9635
“Multi-level engineering facilitates the production of phenylpropanoid compounds in tomato”
Authors: Yang Zhang, et al