KAIST researchers engineer a bacterial strain capable of producing lutein

2022-09-24 03:37:02 By : Ms. Judy Xiong

We use cookies to enhance your experience. By continuing to browse this site you agree to our use of cookies. More info.

A research group at KAIST has engineered a bacterial strain capable of producing lutein. The research team applied systems metabolic engineering strategies, including substrate channeling and electron channeling, to enhance the production of lutein in an engineered Escherichia coli strain. The strategies will be also useful for the efficient production of other industrially important natural products used in the food, pharmaceutical, and cosmetic industries.

Lutein is classified as a xanthophyll chemical that is abundant in egg yolk, fruits, and vegetables. It protects the eye from oxidative damage from radiation and reduces the risk of eye diseases including macular degeneration and cataracts. Commercialized products featuring lutein are derived from the extracts of the marigold flower, which is known to harbor abundant amounts of lutein. However, the drawback of lutein production from nature is that it takes a long time to grow and harvest marigold flowers. Furthermore, it requires additional physical and chemical-based extractions with a low yield, which makes it economically unfeasible in terms of productivity. The high cost and low yield of these bioprocesses has made it difficult to readily meet the demand for lutein.

These challenges inspired the metabolic engineers at KAIST, including researchers Dr. Seon Young Park, Ph.D. Candidate Hyunmin Eun, and Distinguished Professor Sang Yup Lee from the Department of Chemical and Biomolecular Engineering. The team's study entitled "Metabolic engineering of Escherichia coli with electron channeling for the production of natural products" was published in Nature Catalysis on August 5, 2022.

This research details the ability to produce lutein from E. coli with a high yield using a cheap carbon source, glycerol, via systems metabolic engineering. The research group focused on solving the bottlenecks of the biosynthetic pathway for lutein production constructed within an individual cell. First, using systems metabolic engineering, which is an integrated technology to engineer the metabolism of a microorganism, lutein was produced when the lutein biosynthesis pathway was introduced, albeit in very small amounts.

To improve the productivity of lutein production, the bottleneck enzymes within the metabolic pathway were first identified. It turned out that metabolic reactions that involve a promiscuous enzyme, an enzyme that is involved in two or more metabolic reactions, and electron-requiring cytochrome P450 enzymes are the main bottleneck steps of the pathway inhibiting lutein biosynthesis.

To overcome these challenges, substrate channeling, a strategy to artificially recruit enzymes in physical proximity within the cell in order to increase the local concentrations of substrates that can be converted into products, was employed to channel more metabolic flux towards the target chemical while reducing the formation of unwanted byproducts.

Furthermore, electron channeling, a strategy similar to substrate channeling but differing in terms of increasing the local concentrations of electrons required for oxidoreduction reactions mediated by P450 and its reductase partners, was applied to further streamline the metabolic flux towards lutein biosynthesis, which led to the highest titer of lutein production achieved in a bacterial host ever reported. The same electron channeling strategy was successfully applied for the production of other natural products including nootkatone and apigenin in E. coli, showcasing the general applicability of the strategy in the research field.

It is expected that this microbial cell factory-based production of lutein will be able to replace the current plant extraction-based process."

Dr. Seon Young Park, first author of the paper

She explained that another important point of the research is that integrated metabolic engineering strategies developed from this study can be generally applicable for the efficient production of other natural products useful as pharmaceuticals or nutraceuticals.

"As maintaining good health in an aging society is becoming increasingly important, we expect that the technology and strategies developed here will play pivotal roles in producing other valuable natural products of medical or nutritional importance," explained Distinguished Professor Sang Yup Lee.

The Korea Advanced Institute of Science and Technology (KAIST)

Park, S.Y., et al. (2022) Metabolic engineering of Escherichia coli with electron channelling for the production of natural products. Nature Catalysis. doi.org/10.1038/s41929-022-00820-4.

Posted in: Cell Biology | Biochemistry

Tags: Aging, Cell, Cytochrome P450, E. coli, Electron, Enzyme, Eye, Laboratory, Macular Degeneration, Metabolism, Microbial Cell, Microorganism, pH, Pharmaceuticals, Research, Vegetables

As part of Sepsis Awareness Month, celebrated annually in September, News Medical Speaks to Dr. Ron Daniels, founder, and chief executive of the UK Sepsis Trust, about the significance of sepsis awareness, support for patients, and improving outcomes for sepsis survivors.

To commemorate World Alzheimer's Day, News-Medical speaks to Dr. Meredith Gresham, coordinator of COGNISANCE: Co-Designing Dementia Diagnosis And Post Diagnostic Care, about the project and post-dementia diagnosis care for patients and their families.

For World Sepsis Day 2022, News Medical speaks to Colin Graham, COO of Sepsis Research FEAT, about the importance of sepsis awareness, research, and potentially life-changing breakthroughs.

News-Medical.Net provides this medical information service in accordance with these terms and conditions. Please note that medical information found on this website is designed to support, not to replace the relationship between patient and physician/doctor and the medical advice they may provide.

This site complies with the HONcode standard for trustworthy health information: verify here.

News-Medical.net - An AZoNetwork Site

Owned and operated by AZoNetwork, © 2000-2022