# Synthesis of Plant-Inspired O‑Acetylated Hemicellulose Structures in the Yeast Yarrowia lipolytica

## TL;DR

Scientists engineered yeast to produce plant-like hemicellulose structures with O-acetylation, opening new possibilities for biotech applications.

## Contribution

The study demonstrates the first microbial synthesis of O-acetylated hemicellulose structures using Yarrowia lipolytica.

## Key findings

- Yeast successfully produced β-glucomannan and β-glucan hemicellulose structures similar to those in plants.
- O-acetylation of these hemicellulose structures was achieved through the expression of plant O-acetyltransferases.
- The engineered yeast can generate structurally complex hemicellulose with potential for biotechnological use.

## Abstract

Hemicelluloses are
a group of plant cell wall polysaccharides
characterized
by their high structural complexity. These glycans are part of an
intricate composite polymer network that contribute to the mechanical
strength and flexibility of plant cell walls. Hemicellulose structural
and functional diversity is further enhanced by the presence of chemical
modifications, such as O-acetylation, altering the
polysaccharide’s physicochemical properties and the overall
functionality. Plant-derived hemicellulose glycans hold great promise
for a range of biotechnological applications in a bioeconomy including
biomaterials and pharmaceuticals. Synthetic biology approaches have
the potential to produce hemicellulose polymers in microbial factories
replicating the biosynthetic pathways observed in plants. In this
study, we successfully reconstructed in the yeast Yarrowia
lipolytica the biosynthesis of two hemicellulose backbone
structures i.e., β-glucomannan (GM) and β-glucan, by the
expression of glycosyltransferases of diverse plant origins. Oligosaccharide
mass profiling combined with compositional and glycosidic linkage
analysis confirmed the production of hemicellulose structures analogous
to those found in the original plant systems. Furthermore, the additional
expression of plant hemicellulose-specific O-acetyltransferases
resulted in the biosynthesis of O-acetylated GM and O-acetylated glucan polymers, expanding the repertoire of
hemicellulose structures produced in this yeast. These findings demonstrate
the feasibility of generating not only compositionally diverse plant-like
hemicellulose backbone polymers in microbial systems, but also more
structurally complex O-acetylated variants beyond
what is found in nature. The use of Y. lipolytica as a biofactory for designer glycans expands the potential of microbial
glycoengineering and provides a platform for sustainable production
of functionalized polysaccharides with tailored physicochemical properties
optimized for specific biotechnological applications.