Genomics and biochemical analyses reveal a metabolon key to β-L-ODAP biosynthesis in Lathyrus sativus
Anne Edwards, Isaac Njaci, Abhimanyu Sarkar, Zhouqian Jiang, Gemy Kaithakottil, Christopher Moore, Jitender Cheema, Clare E. M. Stevenson, Martin Rejzek, Petr Novák, Marielle Vigouroux, Martin Vickers, Roland H. M. Wouters, Pirita Paajanen, Burkhard Steuernagel, Jonathan D. Moore, Janet Higgins, David Swarbreck, Stefan Martens, Colin Y. Kim, Jing‐Ke Weng, Sagadevan Mundree, Benjamin Kilian, Shiv Kumar, Matthew Loose, Levi Yant, Jir̆ı́ Macas, Trevor L. Wang, Cathie Martin, Peter M. F. Emmrich
Abstract
Grass pea (Lathyrus sativus L.) is a rich source of protein cultivated as an insurance crop in Ethiopia, Eritrea, India, Bangladesh, and Nepal. Its resilience to both drought and flooding makes it a promising crop for ensuring food security in a changing climate. The lack of genetic resources and the crop's association with the disease neurolathyrism have limited the cultivation of grass pea. Here, we present an annotated, long read-based assembly of the 6.5 Gbp L. sativus genome. Using this genome sequence, we have elucidated the biosynthetic pathway leading to the formation of the neurotoxin, β-L-oxalyl-2,3-diaminopropionic acid (β-L-ODAP). The final reaction of the pathway depends on an interaction between L. sativus acyl-activating enzyme 3 (LsAAE3) and a BAHD-acyltransferase (LsBOS) that form a metabolon activated by CoA to produce β-L-ODAP. This provides valuable insight into the best approaches for developing varieties which produce substantially less toxin.