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Title: Elucidating the metabolic roles of isoflavone synthase-mediated protein-protein interactions in yeast
Abstract Transient plant enzyme complexes formed via protein-protein interactions (PPIs) play crucial regulatory roles in secondary metabolism. Complexes assembled on cytochrome P450s (CYPs) are challenging to characterize metabolically due to difficulties in decoupling the PPIs’ metabolic impacts from the CYPs’ catalytic activities. Here, we developed a yeast-based synthetic biology approach to elucidate the metabolic roles of PPIs between a soybean-derived CYP, isoflavone synthase (GmIFS2), and other enzymes in isoflavonoid metabolism. By reconstructing multiple complex variants with an inactive GmIFS2 in yeast, we found that GmIFS2-mediated PPIs can regulate metabolic flux between two competing pathways producing deoxyisoflavonoids and isoflavonoids. Specifically, GmIFS2 can recruit chalcone synthase (GmCHS7) and chalcone reductase (GmCHR5) to enhance deoxyisoflavonoid production or GmCHS7 and chalcone isomerase (GmCHI1B1) to enhance isoflavonoid production. Additionally, we identified and characterized two novel isoflavoneO-methyltransferases interacting with GmIFS2. This study highlights the potential of yeast synthetic biology for characterizing CYP-mediated complexes.  more » « less
Award ID(s):
2338009
PAR ID:
10568731
Author(s) / Creator(s):
; ;
Publisher / Repository:
bioRxiv
Date Published:
Format(s):
Medium: X
Institution:
bioRxiv
Sponsoring Org:
National Science Foundation
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