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Abstract The members of the infant microbiome are governed by feeding method (breastmilk vs. formula). Regardless of the source of nutrition, a competitive growth advantage can be provided to commensals through prebiotics – either human milk oligosaccharides (HMOs) or plant oligosaccharides that are supplemented into formula. To characterize how prebiotics modulate commensal – pathogen interactions, we have designed and studied a minimal microbiome where a pathogen,Streptococcus agalactiaeengages with a commensal,Streptococcus salivarius. We discovered that whileS. agalactiaesuppresses the growth ofS. salivariusvia increased lactic acid production, galacto‐oligosaccharides (GOS) supplementation reverses the effect. This result has major implications in characterizing how single species survive in the gut, what niche they occupy, and how they engage with other community members.
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Traversing Biosynthetic Carbocation Landscapes in the Total Synthesis of Andrastin and Terretonin Meroterpenes
Abstract Meroterpenes derived from dimethylorsellinic acid (DMOA) and farnesyl pyrophosphate have attracted much biosynthetic attention, yet only recently have synthetic solutions to any family members appeared. A key point of divergence in DMOA‐derived meroterpene biosynthesis is the protoaustinoid A carbocation, which can be diverted to either the berkeleyone, andrastin, or terretonin structural classes by cyclase‐controlled rearrangement pathways. Shown herein is that the protoaustinoid bicyclo[3.3.1]nonane nucleus can be reverted to either andrastin or terretonin ring systems under abiotic reaction conditions. The first total syntheses of members of these natural product families are reported as their racemates.
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- Award ID(s):
- 1554544
- PAR ID:
- 10039875
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Angewandte Chemie International Edition
- Volume:
- 56
- Issue:
- 41
- ISSN:
- 1433-7851
- Page Range / eLocation ID:
- p. 12498-12502
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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