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Monitoring of engineered Saccharomyces cerevisiae strains for stability variations and genetic mutations during 7-day tank fermentations

Anderes, Tegan LU (2023) KMBM01 20231
Applied Microbiology
Biotechnology
Abstract
The groundbreaking field of synthetic biology has immense potential to revolutionize our society by reducing our reliance on petroleum. With a growing demand for sustainable ingredients and molecules, companies like Amyris, who have successfully developed and commercialized this technology, are poised to reap significant rewards. I am privileged to work for a scientifically advanced organization that values innovation, and my work has provided me with extensive knowledge in strain engineering. My thesis research focused on the stability of S. cerevisiae strains during 7-day tank fermentations, where I probed potential genetic mutations that could occur. I spearheaded the monitoring of production strains during engineering changes made to a... (More)
The groundbreaking field of synthetic biology has immense potential to revolutionize our society by reducing our reliance on petroleum. With a growing demand for sustainable ingredients and molecules, companies like Amyris, who have successfully developed and commercialized this technology, are poised to reap significant rewards. I am privileged to work for a scientifically advanced organization that values innovation, and my work has provided me with extensive knowledge in strain engineering. My thesis research focused on the stability of S. cerevisiae strains during 7-day tank fermentations, where I probed potential genetic mutations that could occur. I spearheaded the monitoring of production strains during engineering changes made to a genetic switch, stability constructs, and pathway enzymes. Through
stability experiments such as surveillance and raindrop, I collected qualitative and quantitative evidence, yielding several key findings. These included stability variation in genetic isolates with a new genetic switch, a lysine stability design that eliminated switch breakage, and a strain with significantly enhanced
stability attributed partly to a crucial pathway enzyme. (Less)
Popular Abstract
With the future of petroleum-based products under scrutiny, there is a growing need for
alternative chemical and ingredient production methods. Biomanufacturing is one such area of interest,
which involves using genetically engineered synthetic pathways in biological hosts to create these
molecules. Several pioneering companies are focusing on synthetic biology, including Amyris, where I
work as an associate scientist. Amyris is dedicated to the renewable and ethical sourcing of raw materials
and sustainable science. The company mission to “do good science” is a mantra I highly support. I am
fortunate enough to have been able to share some of my project work on this topic in my thesis.
In order to grasp the scientific principles at... (More)
With the future of petroleum-based products under scrutiny, there is a growing need for
alternative chemical and ingredient production methods. Biomanufacturing is one such area of interest,
which involves using genetically engineered synthetic pathways in biological hosts to create these
molecules. Several pioneering companies are focusing on synthetic biology, including Amyris, where I
work as an associate scientist. Amyris is dedicated to the renewable and ethical sourcing of raw materials
and sustainable science. The company mission to “do good science” is a mantra I highly support. I am
fortunate enough to have been able to share some of my project work on this topic in my thesis.
In order to grasp the scientific principles at work, I'll begin with a common process that many are
familiar with: alcohol fermentation. The necessary ingredients are fairly simple: water, sugar and a
fermentative organism such as yeast. This produces a well-known substance called ethanol. However,
have you ever considered if it were possible to use these same components to generate a completely
different type of molecule? How could this be accomplished?
Well, with the power of gene editing tools (such as CRISPR), a biological organism such as baker’s
yeast, S. cerevisiae, can be engineered to produce a multitude of molecules by tinkering with different
metabolic pathways and inputting genes from other species. This becomes a synthetic biologist or strain
engineer’s playground to construct novel and imaginative pathways that effectively hijack the yeast
metabolism and give it new genetic instructions. Understandably, with the modification of genes and
pathways, the biological host will often experience a variety of stress responses leading to strain
instability. Moreover, the engineered production strains grow much slower than wild-type yeast, and this
selective pressure allows for non-producing strains to outcompete during fermentation. These stressors
and growth differential often cause a reduction in productivity and will lead to less of the desired molecule
being produced – this ultimately is bad for business.
My thesis project focused primarily on the stability of yeast production strains in fermentations
by monitoring drops in molecule titer, growth parameters, color differentiation, and in some cases
chemical intermediate build-up. I was able to elucidate stability variations in genetic isolates with a new
genetic switch, a lysine stability design that eliminated genetic breakage, and a strain with significantly
enhanced stability attributed partly to a new pathway enzyme. (Less)
Please use this url to cite or link to this publication:
author
Anderes, Tegan LU
supervisor
organization
course
KMBM01 20231
year
type
H2 - Master's Degree (Two Years)
subject
keywords
synthetic biology, genetic engineering, industrial fermentation, whole genome sequencing, applied microbiology
language
English
id
9139865
date added to LUP
2023-10-13 09:11:15
date last changed
2023-10-13 09:11:15
@misc{9139865,
  abstract     = {{The groundbreaking field of synthetic biology has immense potential to revolutionize our society by reducing our reliance on petroleum. With a growing demand for sustainable ingredients and molecules, companies like Amyris, who have successfully developed and commercialized this technology, are poised to reap significant rewards. I am privileged to work for a scientifically advanced organization that values innovation, and my work has provided me with extensive knowledge in strain engineering. My thesis research focused on the stability of S. cerevisiae strains during 7-day tank fermentations, where I probed potential genetic mutations that could occur. I spearheaded the monitoring of production strains during engineering changes made to a genetic switch, stability constructs, and pathway enzymes. Through
stability experiments such as surveillance and raindrop, I collected qualitative and quantitative evidence, yielding several key findings. These included stability variation in genetic isolates with a new genetic switch, a lysine stability design that eliminated switch breakage, and a strain with significantly enhanced
stability attributed partly to a crucial pathway enzyme.}},
  author       = {{Anderes, Tegan}},
  language     = {{eng}},
  note         = {{Student Paper}},
  title        = {{Monitoring of engineered Saccharomyces cerevisiae strains for stability variations and genetic mutations during 7-day tank fermentations}},
  year         = {{2023}},
}