Yeast Mutant HAP4 Expression Ethanol Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing yeast mutants used for producing desired products, such as lactic acid, face challenges in maintaining high growth and fermentation rates while reducing ethanol production, as disrupting genes involved in ethanol pathways often leads to decreased fermentation capacity and insufficient ethanol reduction.
Innovation Solution
A yeast mutant is developed by introducing a foreign gene encoding an enzyme involved in the desired product's synthesis and constitutively expressing the HAP4 gene, which enhances the production of the desired product without compromising growth and fermentation rates, specifically by lowering alcohol productivity through enzymes like pyruvate decarboxylase and alcohol dehydrogenase disruption.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-generated harmful factors
If genes involved in ethanol production pathway (pyruvate decarboxylase gene, alcohol dehydrogenase gene) are disrupted to reduce ethanol production, then ethanol production capacity decreases, but proliferation capacity and fermentation capacity significantly decrease
Solution Approach 1:
The invention extracts and removes the harmful function (ethanol production) by disrupting specific genes (PDC1, PDC5, PDC6, ADH1, ADH2) in the ethanol production pathway, while preserving the beneficial functions (proliferation and fermentation capacity) through careful selection of which genes to disrupt and which to maintain
Solution Approach 2:
The invention applies local quality by selectively disrupting only certain genes in the ethanol production pathway (pyruvate decarboxylase genes and alcohol dehydrogenase genes) while leaving other parts of the metabolic pathway intact, thereby achieving localized reduction of ethanol production without globally affecting cellular functions
2Object-generated harmful factors
If genes involved in ethanol production pathway are disrupted to reduce ethanol production, then ethanol production capacity decreases, but desired product formation is insufficient
Solution Approach 1:
The invention segments the metabolic pathways by separately controlling the ethanol production pathway (through gene disruption) and the desired product synthesis pathway (through foreign gene introduction), allowing independent optimization of each pathway without mutual interference
Solution Approach 2:
The invention merges two separate genetic modifications: (1) disruption of endogenous ethanol production genes and (2) introduction of foreign genes for desired product synthesis, creating a combined strain that simultaneously achieves ethanol reduction and enhanced desired product formation
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The yeast mutant effectively produces desired products like lactic acid at improved yields and reduced ethanol levels, maintaining excellent growth and fermentation rates, thereby reducing production costs.
Implementation Method 1
a yeast mutant into which a foreign gene that encodes an enzyme involved in the production of a desired product and a HAP4 gene that can be constitutively expressed have been introduced
Implementation Method 2
a foreign gene that encodes an enzyme involved in the production of a desired product
Implementation Method 3
maintaining its growth rate and fermentation rate
Data Source
AI summary
The present invention provides, inter alia, an improvement in the production of a desired product from yeast, wherein the growth rate and fermentation rate of the yeast are maintained at excellent levels. The present invention also provides, inter alia, for the introduction of a foreign gene into a yeast host cell, wherein the foreign gene encodes an enzyme involved in the production of a desired product. The yeast may also constitutively express a HAP4 gene, or a homologous gene thereof, to significantly improve the ability of the yeast to produce the desired product while maintaining its growth rate and fermentation rate. In some embodiments, a yeast mutant is used which is a mutant strain having lowered alcohol productivity vis-à-vis a wild-type strain.