Developing oleaginous yeast as model organisms for lipid production

Over the last few decades, there has been a consistent research effort to reduce the dependence on fossil fuel-derived feedstocks. Plant biomass provides a sustainable alternative to crude-based feedstocks. Oleaginous yeasts (yeasts that can store 20% w/w lipids) are an emerging class of microorganisms, producing biofuels and bioproducts from renewable biomass. While yeasts like Rhodosporiduim toruloides, Lipomyces starkeyi, and Yarrowia lipolytica are ideal hosts for lipid production from biomass, we are limited in our understanding of the physiology of these yeasts. The work presented in this thesis aims at understanding the mechanisms involved in sugar utilization and lipid accumulation in oleaginous yeasts using various bioinformatics tools and mathematical modeling. This work improves our understanding of these yeasts and helps in the rational design of increased lipid-producing strains. Chapter 1 provides a brief introduction to the fermentation of lignocellulosic hydrolysates. Chapter 2 reports the substrate uptake and utilization pathways in the oleaginous yeast Rhodosporiduim toruloides. In Chapter 3, we report the sugar utilization pathways in Lipomyces starkeyi. Using RNA sequencing and metabolomics, we identify the genes and pathways involved in the utilization of various sugars in both the yeasts. This work was done in collaboration with Dr. Sujit Jagtap and Dr. JingJing-Liu. Chapter 4 identifies the transporters involved in sugar uptakes in yeasts and compares them to known transporters in plants. We characterize the transporter LST1_205437 from the yeast Lipomyces starkeyi, which is capable of transporting glucose and xylose simultaneously. This work was done in collaboration with Drs. Nurzhan Kuanyshev, Sujit Jagtap and JingJing-Liu. Chapter 5 discusses the insertion of a thioesterase gene in the yeast Yarrowia lipolytica for the production of medium chain alcohols. We present a bioinformatics pipeline to identify the gene's location, copy number variation, and plasmid insertion. Chapter 6 summarizes this work and discusses the next steps toward developing these yeasts as model organisms.

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Chemical Engineering

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2022

Author dc:creator

• Deewan, Anshu

Contributors dc:contributor

• Rao, Christopher V
• Kraft, Mary L
• Shukla, Diwakar
• Jin, Yong-Su

• Oleaginous yeast
• transcriptomics
• RNA-seq
• bioinformatics

Statement dc:rights

• Copyright 2022 Anshu Deewan

Language dc:language

en, eng

Handle dc:identifier

https://hdl.handle.net/2142/115932

OAI record oai:identifier

https://www.ideals.illinois.edu/oai-pmh?verb=GetRecord&metadataPrefix=etdms&identifier=oai%3Awww.ideals.illinois.edu%3A2142%2F115932