Related Experiment Video
Updated: Jun 5, 2026
07:24
Production of Chemicals by Klebsiella pneumoniae Using Bamboo Hydrolysate as Feedstock
Published on: June 29, 2017
Engineering aspartate metabolism improves β-alanine-based 3-hydroxypropionic acid production in Saccharomyces
Deokyeol Jeong1, Luping Xu2, Jikai Zhao3
1Department of Food Science, Purdue University, West Lafayette, IN 47907, USA; Whistler Center for Carbohydrate Research, Purdue University, West Lafayette, IN 47907, USA; Department of Food Science and Technology, Kongju National University, Yesan 32439, Republic of Korea.
Bioresource Technology
|March 2, 2026
Summary
Engineered yeast efficiently produces 3-hydroxypropionic acid (3-HP) from xylose, overcoming previous limitations. This advancement offers a sustainable platform for biorefinery chemical production using lignocellulosic biomass.
Area of Science:
- Biotechnology
- Metabolic Engineering
- Synthetic Biology
Background:
- 3-Hydroxypropionic acid (3-HP) is a key industrial chemical precursor.
- Current microbial 3-HP production from lignocellulosic biomass faces challenges in xylose utilization and pathway efficiency.
Purpose of the Study:
- To engineer Saccharomyces cerevisiae for high-level 3-HP production from xylose.
- To refine the β-alanine metabolic route for enhanced 3-HP synthesis.
Main Methods:
- Introduced a heterologous pathway with Tribolium castaneum aspartate decarboxylase (TcPAND), Bacillus cereus β-alanine-pyruvate aminotransferase (BcBAPAT), and Escherichia coli 3-hydroxypropanoate dehydrogenase (EcydfG).
- Reconfigured mitochondrial aspartate generation and intermediate amino acid pathways.
- Optimized culture conditions and employed fed-batch fermentation.
Main Results:
- Achieved a 3-HP concentration of 32.9 g/L with a yield of 0.21 C-mol/C-mol xylose.
- Demonstrated 3-HP production from deacetylated hemp stalk hydrolysate, reaching a titer of 6.9 g/L.
Conclusions:
- Engineered yeast provides a viable platform for efficient and sustainable 3-HP production in biorefineries.
- The refined β-alanine route enhances 3-HP synthesis from xylose-derived feedstocks.
Keywords:
Acetate-rich biomassBiotransformationCRISPR/Cas9Hydroxycarboxylic acidMitochondrial aspartateMore Related Videos
Related Concept Videos
01:20Fates of Pyruvate
Pyruvate is the end product of glycolysis, where glucose is oxidized to pyruvate, simultaneously reducing NAD+ to NADH. Two molecules of ATP are also produced by substrate-level phosphorylation.
In aerobic organisms, pyruvate is metabolized via the citric acid cycle to produce reduced coenzymes NADH and FADH2. These coenzymes are then oxidized in the electron transport chain to produce ATP and, in the process, regenerate the NAD+ and FAD. As seen in some cell types and organisms, fermentation...
In aerobic organisms, pyruvate is metabolized via the citric acid cycle to produce reduced coenzymes NADH and FADH2. These coenzymes are then oxidized in the electron transport chain to produce ATP and, in the process, regenerate the NAD+ and FAD. As seen in some cell types and organisms, fermentation...
01:18Amino Acid Catabolism
Microorganisms rely on proteins as an essential carbon and energy source, particularly in environments with limited polysaccharides or lipids. However, proteins are too large to cross the plasma membrane unaided, necessitating enzymatic degradation. Microbes secrete extracellular proteases and peptidases that hydrolyze proteins into peptides, which can then be transported across the membrane. Once inside the cell, intracellular proteases degrade these peptides into free amino acids, which...
01:29Amino Acid Biosynthetic Pathways
Amino acid biosynthesis is essential for cell growth, protein synthesis, and metabolic regulation. Cells generate essential and non-essential amino acids from metabolic intermediates to sustain vital biological functions. These intermediates originate from key metabolic pathways: glycolysis, the tricarboxylic acid (TCA) cycle, and the pentose phosphate pathway. Important precursors include α-ketoglutarate, pyruvate, oxaloacetate, phosphoenolpyruvate, and erythrose-4-phosphate, which provide...
01:22Bioreactor Controls-III
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...
01:27Production of Alcohol
Continuous fermentation is a key strategy in industrial ethanol production, particularly when efficiency, scalability, and high yields are essential. This approach allows for uninterrupted operation and optimized resource utilization. The primary feedstock, corn starch, undergoes enzymatic hydrolysis facilitated by α-amylase and glucoamylase. These enzymes break down the starch into fermentable sugars such as glucose, which are readily assimilated by fermentative microorganisms.Fermentation...
01:25Production of Organic Acids
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...