Rice University bioengineers have made an advance in tapping the immense potential of "hairy roots"—a type of tumour that forms on plants infected by the soil bacterium Agrobacterium rhizogenes—as natural factories to produce medicines, food flavourings, and other commercial products.
"The species of periwinkle that we're studying produces a wide variety of alkaloids -- including the anti-cancer drugs vincristine and vinblastine," said Ka-Yiu San, co-author of the paper available online and slated to be published in Biotechnology Progress.
"Hairy roots have a number of advantages over cell cultures as a production platform for these compounds," the researcher added.
Scientists have for long believed that the production prowess of hairy roots can be harnessed for the industry, but the biggest challenge before them was to determine the long-term stability of the genetically altered roots.
San and Christie Peebles, a Rice graduate student, has now described the methods they used to keep a transgenic hairy root culture alive for four-and-a-half years.
At the outset, the researchers infected a periwinkle plant with a bacterium carrying a gene for fluorescence. They maintained a stable root culture with the characteristic fluorescent glow produced by the gene by transferring root tips into fresh liquid every four weeks.
San and his colleagues are now hoping to make genetic modifications to the metabolic pathways of the transgenic periwinkle roots. They believe that such changes will allow them to produce far more vincristine and vinblastine than is normally produced by a regular periwinkle plant.