The soybean cyst nematode is a parasitic worm which infects the roots of soya bean, a commercially important crop from which numerous food products are obtained. Due to the devastating action exerted on the crop, this pathogen represents a major agricultural problem.

Shiming Liu, Southern Illinois University, USA, and colleagues discovered that soya bean strains naturally resistant to the worm are protected from its infection by mutations occurring in the serine hydroxymethyltransferase protein. In particular, mutations in the aminoacids 61 and 125 altered the regulation of the enzyme, thereby affecting its ability to simultaneously convert L-serine to glycine and tetrahydrofolate to N5,N10-methylene tetrahydrofolate.

By pointing out the biochemistry underlying resistance of soybeans to the parasite, the study may help developing new strategies to strengthen it.

• A soybean cyst nematode resistance gene points to a new mechanism of plant resistance to pathogens,
  S. Liu, P. K. Kandoth, S. D. Warren, G. Yeckel, R. Heinz, J. Alden, C. Yang, A. Jamai, T. El-Mellouki, P. S. Juvale, J. Hill, T.  J. Baum, S.Cianzio, S. A. Whitham, D. Korkin, M. G. Mitchum, K. Meksem,
  Nature 2012, 492 (7428), 256–260.
  DOI: 10.1038/nature11651