Related Experiment Video
Updated: May 5, 2026
14:53
Techniques for the Evolution of Robust Pentose-fermenting Yeast for Bioconversion of Lignocellulose to Ethanol
Published on: October 24, 2016
11.0K
Efficient ethanol production from brown macroalgae sugars by a synthetic yeast platform
Maria Enquist-Newman1, Ann Marie E Faust1, Daniel D Bravo1
11] Bio Architecture Lab Inc., 604 Bancroft Way, Suite A, Berkeley, California 94710, USA [2].
Nature
|December 3, 2013
Summary
Brown macroalgae can be used for sustainable biofuels. Researchers engineered yeast to efficiently metabolize alginate and mannitol from algae, enabling significant ethanol production comparable to traditional feedstocks.
Area of Science:
- Biotechnology
- Renewable Energy
- Marine Resources
Background:
- Growing demand for food and fuel necessitates sustainable feedstocks.
- Brown macroalgae offer a promising, underutilized resource.
- Current industrial microbes like Saccharomyces cerevisiae lack efficient pathways for alginate and mannitol utilization.
Purpose of the Study:
- To engineer Saccharomyces cerevisiae for efficient brown macroalgae feedstock utilization.
- To enable commercial-scale biofuel production from alginate and mannitol.
- To discover and implement novel transporters for key algal sugars.
Main Methods:
- Discovered and characterized a novel alginate monomer (DEHU) transporter from Asteromyces cruciatus.
- Genomically integrated the DEHU transporter gene and bacterial alginate catabolism genes into S. cerevisiae.
- Dereguled native mannitol catabolism pathways in S. cerevisiae.
- Adapted the engineered strain for anaerobic growth and fermentation.
Main Results:
- Engineered S. cerevisiae efficiently metabolized both DEHU and mannitol.
- Achieved significant ethanol fermentation from these sugars under anaerobic conditions.
- Obtained ethanol titers of 4.6% (v/v) and yields up to 83% of theoretical maximum.
Conclusions:
- Demonstrated the feasibility of using brown macroalgae as a comprehensive feedstock for biofuels.
- Established a platform for producing biofuels and renewable chemicals from algal sugars.
- Algae-based feedstocks can be competitive with traditional arable-land-based resources.
Related Concept Videos
01:25Biofuels
108
The microbial conversion of organic matter into biofuels holds potential as a renewable energy source. Among biofuel sources, microalgae are recognized as a highly efficient and adaptable feedstock for biodiesel production, owing to their rapid biomass accumulation, elevated lipid productivity, and capacity to proliferate in diverse aquatic systems, including freshwater, marine, and wastewater habitats. Unlike terrestrial crops, microalgae do not compete for land and can achieve significantly...
108
01:22Bioreactor Controls-III
70
Strain improvement is a foundational strategy in industrial microbiology aimed at maximizing microbial productivity, particularly because natural isolates typically yield commercially valuable products in very low concentrations. Although optimizing the culture medium and environmental conditions can improve yields, these adjustments are inherently limited by the organism’s genetic potential. As a result, the focus shifts toward genetic modifications to enhance biosynthetic capacity. The...
70
01:23Microbial Fermentation
1.8K
Fermentation is a crucial anaerobic metabolic process that enables microbes to derive energy from sugar without relying on oxygen or an electron transport chain. This process is fundamental to various biological and industrial applications and is classified based on the metabolic products generated.Role of Pyruvate in FermentationPyruvate and its derivatives serve as key electron acceptors in fermentative pathways. The oxidation of NADH to regenerate NAD+ is essential for the continuation of...
1.8K
01:25Microbes in Beverage Production
300
Alcoholic beverages such as wine, beer, and spirits are the products of microbial fermentation processes that transform simple sugars into ethanol and a wide array of complex flavor compounds. These transformations rely on the metabolic activities of specific yeasts and bacteria, which are selected and controlled to yield the desired beverage characteristics.Wine Fermentation and MaturationWine production begins with the crushing of grapes to release juice and pulp, forming a must that is...
300
01:25Production of Organic Acids
111
Lactic acid, an important organic acid extensively applied in food, pharmaceutical, and biodegradable polymer industries, is primarily produced via microbial fermentation. This method is favored over chemical synthesis due to its environmental sustainability and capacity for enantiomerically pure product formation. Among various microbial processes, the fermentation of starch-based substrates stands out due to the abundance and renewability of raw materials like corn and potatoes.Hydrolysis of...
111
01:21Green Algae
1.1K
Green algae, also referred to as chlorophytes, are different from red algae in having the chloroplasts containing chlorophylls a and b, which give them their distinct green hue. However, they lack phycobiliproteins, preventing them from developing the red or blue-green pigmentation seen in red algae. In terms of photosynthetic pigment composition, green algae closely resemble plants and share a close evolutionary relationship with them. Taxonomically Green algae belong to Phylum Chlorophyta in...
1.1K