Nature Communications (Oct 2023)

Insights into the missing apiosylation step in flavonoid apiosides biosynthesis of Leguminosae plants

  • Hao-Tian Wang,
  • Zi-Long Wang,
  • Kuan Chen,
  • Ming-Ju Yao,
  • Meng Zhang,
  • Rong-Shen Wang,
  • Jia-He Zhang,
  • Hans Ågren,
  • Fu-Dong Li,
  • Junhao Li,
  • Xue Qiao,
  • Min Ye

DOI
https://doi.org/10.1038/s41467-023-42393-1
Journal volume & issue
Vol. 14, no. 1
pp. 1 – 16

Abstract

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Abstract Apiose is a natural pentose containing an unusual branched-chain structure. Apiosides are bioactive natural products widely present in the plant kingdom. However, little is known on the key apiosylation reaction in the biosynthetic pathways of apiosides. In this work, we discover an apiosyltransferase GuApiGT from Glycyrrhiza uralensis. GuApiGT could efficiently catalyze 2″-O-apiosylation of flavonoid glycosides, and exhibits strict selectivity towards UDP-apiose. We further solve the crystal structure of GuApiGT, determine a key sugar-binding motif (RLGSDH) through structural analysis and theoretical calculations, and obtain mutants with altered sugar selectivity through protein engineering. Moreover, we discover 121 candidate apiosyltransferase genes from Leguminosae plants, and identify the functions of 4 enzymes. Finally, we introduce GuApiGT and its upstream genes into Nicotiana benthamiana, and complete de novo biosynthesis of a series of flavonoid apiosides. This work reports an efficient phenolic apiosyltransferase, and reveals mechanisms for its sugar donor selectivity.