Related Experiment Video
Updated: Apr 5, 2026
08:14
Scalable Step-by-Step Approach of Sustainable Bioplastic Production from Food Waste
Published on: July 18, 2025
1.6K
Efficient aspartic acid production by a psychrophile-based simple biocatalyst
Takahisa Tajima1,2, Mai Hamada3, Yutaka Nakashimada3,4
1Department of Molecular Biotechnology, Graduate School of Advanced Sciences of Matter, Hiroshima University, 1-3-1, Kagamiyama, Higashi-Hiroshima, 739-8530, Japan. ttajima@hiroshima-u.ac.jp.
Journal of Industrial Microbiology & Biotechnology
|August 9, 2015
Summary
This study introduces a novel biocatalyst system (PSCat) for efficient aspartic acid production from fumaric acid. The system prevents L-malic acid byproduct formation, enhancing yield for biotechnological applications.
Area of Science:
- Biotechnology
- Enzyme Engineering
- Metabolic Engineering
Background:
- Aspartic acid biosynthesis competes with L-malic acid production in Escherichia coli.
- Psychrophile-based Simple bioCatalyst (PSCat) systems utilize heat-inactivated enzymes for specific bioconversions.
Purpose of the Study:
- To develop a PSCat system for selective conversion of fumaric acid to aspartic acid.
- To investigate the impact of heat inactivation on competing enzymatic activities.
- To evaluate the efficiency and reusability of the PSCat system for aspartic acid production.
Main Methods:
- Expression of E. coli aspartase in psychrophilic Shewanella livingstonensis Ac10.
- Heat treatment of the engineered psychrophilic host at 50 °C for 15 min to create the PSCat.
- Alginate immobilization of the PSCat for repeated use in fumaric acid conversion.
Main Results:
- The PSCat successfully converted fumaric acid to aspartic acid.
- Formation of L-malic acid was prevented due to heat inactivation of endogenous fumarase.
- Alginate-immobilized PSCat achieved high yields and was reusable for nine cycles.
Conclusions:
- The PSCat system offers a viable strategy for selective aspartic acid production.
- Heat inactivation of competing enzymes is effective in enhancing target compound yield.
- PSCat technology presents a promising approach for biotechnological production of valuable compounds.
More Related Videos
Related Concept Videos
01:25Production of Organic Acids
73
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...
73
01:22Bioreactor Controls-III
54
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...
54
01:27Production of Antibiotics
83
Penicillin, one of the earliest and most widely used antibiotics, is produced industrially by the filamentous fungus Penicillium chrysogenum. Large stirred-tank bioreactors ranging from tens to hundreds of thousands of liters maintain tightly controlled temperature, pH, and dissolved oxygen conditions to support fungal metabolism and maximize antibiotic yield. Penicillin is a secondary metabolite, synthesized primarily during the stationary growth phase, which requires a carefully managed...
83
01:18Amino Acid Catabolism
1.6K
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...
1.6K
01:30Production of Pharmaceuticals
65
Industrial insulin production uses genetically engineered E. coli expressing a proinsulin gene controlled by a tryptophan promoter and containing a methionine linker for later cleavage. The cells also carry ampicillin resistance for selective growth. Seed cultures are stored at −80 °C and production begins by thawing a small amount to inoculate starter cultures, which are progressively scaled to a 50,000-L bioreactor. In the bioreactor, E. coli grow in nutrient-rich media under...
65
01:28Microbial Bioremediation of Plastics
73
Polyethylene terephthalate (PET) is a synthetic polymer widely utilized in the packaging industry, particularly for bottles and containers. Due to its chemical stability and durability, PET accumulates in the environment, contributing significantly to plastic pollution. It comprises repeating units of terephthalic acid and ethylene glycol, resulting in a semi-crystalline structure that is resistant to natural degradation processes.A notable breakthrough in plastic biodegradation came with the...
73