Engineered Microorganisms for Ethanol Production
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current microorganisms used for ethanol production from starch and lignocellulosic feedstocks have suboptimal yields and are inhibited by by-products generated during hydrolysis, requiring more efficient and robust strains that can operate under adverse conditions.
Innovation Solution
Genetically engineered Saccharomyces cerevisiae and Escherichia coli strains with specific gene duplications and disruptions, such as the lpp1 gene and ENA locus in yeast, and disruptions in genes like zwf and ndh in E. coli, allowing for improved ethanol production from mixed sugar substrates and increased tolerance to inhibitors like acetate and ethanol.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If native microorganisms are used for ethanol conversion, then the process is simple and cost-effective, but the conversion yield is suboptimal and the microorganisms are inhibited by hydrolysis by-products
Solution Approach 1:
The patent applies parameter changes by modifying the genetic composition of microorganisms through gene duplications (lpp1, ENA locus) and disruptions (zwf, ndh, sfcA, maeB, ldhA, frdA, poxB, pta genes). These genetic parameter changes enable the microorganisms to tolerate hydrolysis by-products like acetate and furfural while maintaining high ethanol conversion yields, directly resolving the contradiction between productivity and reliability.
2Productivity
If genetically engineered microorganisms are used to improve ethanol yield, then conversion efficiency increases, but the complexity of the production process increases
Solution Approach 1:
The patent applies segmentation by dividing the genetic engineering approach into specific targetable genes and loci (lpp1, ENA locus, zwf, ndh, sfcA, maeB, ldhA, frdA, poxB, pta). This segmentation allows systematic modification of specific genetic elements to achieve desired traits without requiring complete genome redesign, thus improving ethanol yield while managing engineering complexity through modular genetic targets.
3Adaptability or versatility
If different sugar-containing substrates are converted, then feedstock versatility is achieved, but different culture conditions and microorganisms are required for each substrate
Solution Approach 1:
The patent applies universality by creating genetically engineered microorganisms with multi-functional capabilities to convert various sugar-containing substrates (6-carbon sugars, 5-carbon sugars, and mixed sugars) under unified culture conditions. The engineered strains possess broad substrate utilization capabilities through specific gene modifications, eliminating the need to optimize different microorganisms and culture conditions for each substrate type, thus achieving both versatility and operational simplicity.
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
These engineered strains achieve ethanol yields of up to 95% from 6-carbon sugars and 99% from 5-carbon sugars, with enhanced resistance to inhibitors and faster conversion rates compared to wild-type strains, optimizing sugar-to-ethanol conversion processes.
Implementation Method 1
typically, such yeast convert sugars to ethanol at a yield of at least 95%
Implementation Method 2
such a bacteria can convert 5-carbon sugars to ethanol at a yield of at least 91%, up to a yield of at least 98%
Data Source
AI summary
The present invention describes a number of different microorganisms that have been genetically-engineered to optimize ethanol production. The present invention also describes methods of using such microorganisms to efficiently make ethanol.