A genetic gold mine that can create new medicines is hidden in mint leaves
EAST LANSING, Mich. — A genetic goldmine in mint leaves could hold the key to future (and fresh) medicines and pesticides, a new study reveals. This family of herbs includes more than just mint. It also includes sage, rosemary, basil, and even woody plants like teak. In addition to rattling our senses of smell and taste, a Michigan State University team says that thanks to evolution, this family of plants now contains genes that can benefit human health in a number of ways.
“People easily recognize members of the mint family by their specialized metabolites,” explains Björn Hamberger, associate professor and James K. Billman Jr., MD, Endowed Professor in the College of Natural Sciences, in a college pitch. “The metabolites are an efficient way for plants to defend themselves because they can’t run away.”
“Over millions of years, plants have adapted and evolved for their particular niches where they thrive, and that means these chemistries are diverse and clearly adjusted to their environment,” Hamberger adds. “So we try to identify and discover pathways to these specialized metabolites that plants produce.”
Hamberger has been studying these metabolites, which scientists call terpenoids, since 2016. They are essential to protect plants from both predators and viruses. In terms of our daily lives, manufacturers use terpenoids in organic agrochemicals, antioxidants, cosmetics, and perfumes.
What is hidden in the mint genome?
Working with Robin Buell, a former MSU genomics researcher now at the University of Georgia, Hamberger’s team sequenced the genome of various mint plants. They found that the mint family has evolved over the past 60 to 70 million years, with many varieties now containing a large pool of biosynthetic genes.
A BCG is a group of genes sitting close together in the plant genome participating in the same metabolic pathways. The researchers compare these genes to a string of pearls, where all the pearls are separate but still connected. Researchers Abigail Bryson and Emily Lanier found this BCG in the genome of the beauty berry and in six other species within the mint family.
“We are learning that the physical location of genes within the genome is important,” says Bryson. “It can drive the evolution of specialized metabolic pathways in the plant, leading to a great diversity of interesting natural plant compounds.”
BCGs are a common sight in the bacterial world, but the researchers say their role in plants is still unclear. The new study found that the BCG cluster in the beautyberry plant carries genes that code for two distinct terpenoid pathways. Terpenoids accumulate in multiple areas of mint plants, including the leaves and roots. The study authors believe that these metabolites may play a key role in how these plants adapt to their environment.
“It’s the same base molecule, but each species creates its own version and modifies it in different ways to meet its survival needs,” Lanier explains.
What can scientists do with mint genes?
Previous studies have been able to convert mint plants into useful medicines, such as Indian Coleus, which is now a natural treatment for glaucoma. Hamberger’s team says their genetic findings open the door to more medical breakthroughs, from new drugs to pesticides and antimicrobials.
“Our team is excited about the opportunities within the mint family,” concludes Hamberger. “Those peppermint enzymes, like in the American berry plant, give us the ability to make natural plant products in the lab, including, hopefully in the future, good-smelling natural products. mosquito repellents.”
The study is published in the journal nature communications.
