Transcriptional Reactivation of Lignin Biosynthesis for the Heterologous Production of Etoposide Aglycone in Nicotiana benthamiana

• DOI: 10.1021/acssynbio.2c00289
• Publication Date: 2022-09-19T23:43:15Z
• Authors: Stacie S. Kim; Diego L. Wengier; Carin J. Ragland; Elizabeth S. Sattely
• Keywords: Phenylpropanoid; Podophyllum; Metabolic Engineering; Monolignol; Aglycone

Nicotiana benthamiana is a valuable plant chassis for heterologous production of medicinal natural products. This host well suited the processing organelle-localized enzymes, and conservation primary metabolism across kingdom often provides required plant-specific precursor molecules that feed given pathway. Despite this commonality in metabolism, limited supply and/or competing pathways can interfere with yields Here, we use transient transcriptional reprogramming endogenous N. to drastically improve flux through etoposide pathway derived from Podophyllum spp. Specifically, coexpression single lignin-associated transcription factor, MYB85, genes results unprecedented levels product accumulation leaves: 1 mg/g dry weight (DW) aglycone, 35 DW (-)-deoxypodophyllotoxin, 3.5 (-)-epipodophyllotoxin─up two orders magnitude above previously reported biosynthetic aglycone eight times higher than what observed (-)-deoxypodophyllotoxin native plant. Unexpectedly, activation lignin by factor overexpression also reduces undesired side products likely result metabolism. Our work demonstrates synthetic biosynthesis leaf tissue an effective strategy optimizing compounds phenylpropanoid precursors benthamiana. Furthermore, our highlight engineering value early switch biosynthesis, on-demand modulation monolignol support role MYB46 as master regulator polymer deposition.