Black locust deploys peptides to steer root bacteria into nitrogen fixation

Plants need nitrogen to grow. Many legumes meet this need through a symbiotic relationship: They harbor bacteria that fix atmospheric nitrogen and make it available to the plant. Until now, it was largely unclear how a perennial plant regulates this symbiosis without destroying its bacterial partners. An international team led by TU Braunschweig has now described a previously unknown mechanism: The black locust (Robinia pseudoacacia) employs a newly discovered family of small proteins that specifically "reprogram" its symbiotic bacteria for nitrogen fixation while keeping them alive. The findings are published in Science Advances.