scholarly journals Engineering Microbes to Bio-Upcycle Polyethylene Terephthalate

2021 ◽  
Vol 9 ◽  
Author(s):  
Lakshika Dissanayake ◽  
Lahiru N. Jayakody
Keyword(s):  
Polyethylene Terephthalate ◽  
Metabolic Pathways ◽  
Aquatic Ecosystems ◽  
Value Added ◽  
Building Blocks ◽  
Chemical Recycling ◽  
Plastic Pollution ◽  
Microbial Cell Factories ◽  
Cell Factories ◽  
Value Added Products

Polyethylene terephthalate (PET) is globally the largest produced aromatic polyester with an annual production exceeding 50 million metric tons. PET can be mechanically and chemically recycled; however, the extra costs in chemical recycling are not justified when converting PET back to the original polymer, which leads to less than 30% of PET produced annually to be recycled. Hence, waste PET massively contributes to plastic pollution and damaging the terrestrial and aquatic ecosystems. The global energy and environmental concerns with PET highlight a clear need for technologies in PET “upcycling,” the creation of higher-value products from reclaimed PET. Several microbes that degrade PET and corresponding PET hydrolase enzymes have been successfully identified. The characterization and engineering of these enzymes to selectively depolymerize PET into original monomers such as terephthalic acid and ethylene glycol have been successful. Synthetic microbiology and metabolic engineering approaches enable the development of efficient microbial cell factories to convert PET-derived monomers into value-added products. In this mini-review, we present the recent progress of engineering microbes to produce higher-value chemical building blocks from waste PET using a wholly biological and a hybrid chemocatalytic–biological strategy. We also highlight the potent metabolic pathways to bio-upcycle PET into high-value biotransformed molecules. The new synthetic microbes will help establish the circular materials economy, alleviate the adverse energy and environmental impacts of PET, and provide market incentives for PET reclamation.

scholarly journals Organic Wastes as Feedstocks for Non-Conventional Yeast-Based Bioprocesses

2019 ◽  
Vol 7 (8) ◽  
pp. 229 ◽  
Author(s):  
Diem T. Hoang Do ◽  
Chrispian W. Theron ◽  
Patrick Fickers
Keyword(s):  
Carbon Sources ◽  
Value Added ◽  
Building Blocks ◽  
Organic Wastes ◽  
Cell Factory ◽  
Microbial Cell Factories ◽  
Cell Factories ◽  
Alternative Feedstocks ◽  
Global Population ◽  
By Products

Non-conventional yeasts are efficient cell factories for the synthesis of value-added compounds such as recombinant proteins, intracellular metabolites, and/or metabolic by-products. Most bioprocess, however, are still designed to use pure, ideal sugars, especially glucose. In the quest for the development of more sustainable processes amid concerns over the future availability of resources for the ever-growing global population, the utilization of organic wastes or industrial by-products as feedstocks to support cell growth is a crucial approach. Indeed, vast amounts of industrial and commercial waste simultaneously represent an environmental burden and an important reservoir for recyclable or reusable material. These alternative feedstocks can provide microbial cell factories with the required metabolic building blocks and energy to synthesize value-added compounds, further representing a potential means of reduction of process costs as well. This review highlights recent strategies in this regard, encompassing knowledge on catabolic pathways and metabolic engineering solutions developed to endow cells with the required metabolic capabilities, and the connection of these to the synthesis of value-added compounds. This review focuses primarily, but not exclusively, on Yarrowia lipolytica as a yeast cell factory, owing to its broad range of naturally metabolizable carbon sources, together with its popularity as a non-conventional yeast.

scholarly journals Environment and plastics : A review on greener routes for plastic bottle (PET) waste management through recycling processes

2020 ◽  
Vol 15 (2) ◽  
pp. 105-110
Author(s):  
Swati Singh
Keyword(s):  
Polyethylene Terephthalate ◽  
Value Added ◽  
Waste Recycling ◽  
Operating Conditions ◽  
Chemical Recycling ◽  
Short Term ◽  
Research Papers ◽  
Pet Waste ◽  
Viable Solution ◽  
Value Added Products

Many research papers have been contributed by several authors for making polyethylene terephthalate (PET) waste recycling economically and ecologically more viable as it creates environmental hazards when disposed off after its short term use. Recycling of PET waste was started in last two decades. Most of the authors are devoting their time in getting economically viable solution for development of methods based on either mechanical or chemical recycling. Some success has been obtained in development of chemical recycling methods which provides value added products from PET waste. In this study the operating conditions and mechanism of various recycling processes available for the recycling of polyethylene terephthalate (PET) waste are reported and described.

scholarly journals Recent Advances in Chemical Recycling of Polyethylene Terephthalate Waste into Value Added Products for Sustainable Coating Solutions- Hope Vs Hype

2022 ◽  
Author(s):  
Krishanu Ghosal ◽  
Chinmaya Nayak
Keyword(s):  
Polyethylene Terephthalate ◽  
Daily Life ◽  
Value Added ◽  
Chemical Recycling ◽  
Dinner Table ◽  
Recent Advances ◽  
Value Added Products

In the current era of globalization, plastics are an indispensable part of our daily life; from morning toothbrush to night dinner table, plastics are everywhere in our daily life. In...

Metabolic engineering of glycosylated polyketide biosynthesis

2018 ◽  
Vol 2 (3) ◽  
pp. 389-403 ◽  
Author(s):  
Ramesh Prasad Pandey ◽  
Prakash Parajuli ◽  
Jae Kyung Sohng
Keyword(s):  
Natural Products ◽  
Metabolic Engineering ◽  
Value Added ◽  
Chemical Diversity ◽  
Yeast Cells ◽  
Microbial Cell Factories ◽  
Cell Factories ◽  
Modification Method ◽  
Post Modification ◽  
Microbial Biosynthesis

Microbial cell factories are extensively used for the biosynthesis of value-added chemicals, biopharmaceuticals, and biofuels. Microbial biosynthesis is also realistic for the production of heterologous molecules including complex natural products of plant and microbial origin. Glycosylation is a well-known post-modification method to engineer sugar-functionalized natural products. It is of particular interest to chemical biologists to increase chemical diversity of molecules. Employing the state-of-the-art systems and synthetic biology tools, a range of small to complex glycosylated natural products have been produced from microbes using a simple and sustainable fermentation approach. In this context, this review covers recent notable metabolic engineering approaches used for the biosynthesis of glycosylated plant and microbial polyketides in different microorganisms. This review article is broadly divided into two major parts. The first part is focused on the biosynthesis of glycosylated plant polyketides in prokaryotes and yeast cells, while the second part is focused on the generation of glycosylated microbial polyketides in actinomycetes.

scholarly journals A common approach for absolute quantification of short chain CoA thioesters in industrially relevant gram-positive and gram-negative prokaryotic and eukaryotic microbes

2020 ◽  
Author(s):  
Lars Gläser ◽  
Martin Kuhl ◽  
Sofija Jovanovic ◽  
Michel Fritz ◽  
Bastian Vögeli ◽  
...  
Keyword(s):  
Building Blocks ◽  
Absolute Quantification ◽  
Microbial Cell ◽  
Short Chain ◽  
Enzymatic Reactions ◽  
Gram Positive ◽  
Gram Negative ◽  
Microbial Cell Factories ◽  
Cell Factories ◽  
Coa Thioesters

Abstract Background: Thioesters of coenzyme A participate in 5% of all enzymatic reactions and at least one third of all cellular carbon is typically metabolized through a CoA thioester. In microbial cell factories, they function as building blocks for products of recognized commercial value, including natural products such as polyketides, polyunsaturated fatty acids, biofuels, and biopolymers. A core spectrum of approximately 5 – 10 short chain thioesters is present in many microbes, as inferred from their genomic repertoire. The relevance these metabolites explains the high interest to trace and quantify them in microbial cells.Results: Here, we describe a common workflow for extraction and absolute quantification of short chain CoA thioesters in different gram-positive and gram-negative bacteria and eukaryotic yeast, i.e. Corynebacterium glutamicum, Streptomyces albus, Pseudomonas putida, and Yarrowia lipolytica. The approach detected CoA thioesters down to the level of 40 attomole and exhibited high precision and reproducibility for all microbes as shown by principal component analysis. Furthermore, it provided interesting insights into microbial CoA-spectra. A succinyl-CoA synthase defective mutant of C. glutamicum, exhibited an unaffected level of succinyl-CoA, which indicated a complete compensation of the l-lysine pathway to bypass the disrupted TCA cycle. Methylmalonyl-CoA, an important building block of high-value polyketides, was identified as dominant CoA thioester in the microbe. S. albus revealed a more than 10,000-fold difference in the abundance of intracellular CoA thioesters. A recombinant strain of S. albus, which produced different derivatives of the antituberculosis polyketide pamamycin, revealed a significant depletion of CoA thioesters of the ethylmalonyl CoA pathway, influencing product level and spectrum. Conclusions: The high relevance of short chain CoA thioesters to synthetize industrial products and the interesting insights gained from the examples shown in this work, suggest analyzing these metabolites in microbial cell factories more routinely than done so far. Due to its broad application range, the developed approach appears useful to be applied this purpose. Hereby, the possibility to use on single protocol promises to facilitate automatized efforts, which rely on standardized workflows.

scholarly journals Advancements in Catalytic Conversion of Biomass into Biofuels and Chemicals

Energies ◽  
2020 ◽  
Vol 13 (20) ◽  
pp. 5438
Author(s):  
Chang Geun Yoo ◽  
Tae Hyun Kim
Keyword(s):  
Renewable Resources ◽  
Energy Efficient ◽  
Alternative Fuels ◽  
Value Added ◽  
Catalytic Conversion ◽  
Building Blocks ◽  
Effective Utilization ◽  
Earth Abundant ◽  
Fuels And Chemicals ◽  
Value Added Products

The shortage of resources and increasing climate changes have brought the need for sustainable and renewable resources to people’s attention. Biomass is an earth-abundant material and has great potential as a feedstock for alternative fuels and chemicals. For the effective utilization of biomass, this biopolymer has to be depolymerized and transformed into key building blocks and/or the targeted products, and biological or chemical catalysts are commonly used for the rapid and energy-efficient reactions. This Special Issue introduces recent advances in the catalytic conversion of biomass into biofuels and value-added products.

scholarly journals A bioarchitectonic approach to the modular engineering of metabolism

2017 ◽  
Vol 372 (1730) ◽  
pp. 20160387 ◽  
Author(s):  
Cheryl A. Kerfeld
Keyword(s):  
Metabolic Pathways ◽  
Single Gene ◽  
Lessons Learned ◽  
Green Economy ◽  
Biological Organization ◽  
Microbial Cell Factories ◽  
Cell Factories ◽  
Cellular Compartments ◽  
Synthetic Microbial Communities ◽  
The Continuum

Dissociating the complexity of metabolic processes into modules is a shift in focus from the single gene/gene product to functional and evolutionary units spanning the scale of biological organization. When viewing the levels of biological organization through this conceptual lens, modules are found across the continuum: domains within proteins, co-regulated groups of functionally associated genes, operons, metabolic pathways and (sub)cellular compartments. Combining modules as components or subsystems of a larger system typically leads to increased complexity and the emergence of new functions. By virtue of their potential for ‘plug and play’ into new contexts, modules can be viewed as units of both evolution and engineering. Through consideration of lessons learned from recent efforts to install new metabolic modules into cells and the emerging understanding of the structure, function and assembly of protein-based organelles, bacterial microcompartments, a structural bioengineering approach is described: one that builds from an architectural vocabulary of protein domains. This bioarchitectonic approach to engineering cellular metabolism can be applied to microbial cell factories, used in the programming of members of synthetic microbial communities or used to attain additional levels of metabolic organization in eukaryotic cells for increasing primary productivity and as the foundation of a green economy. This article is part of the themed issue ‘Enhancing photosynthesis in crop plants: targets for improvement’.

scholarly journals Methane monooxygenases: central enzymes in methanotrophy with promising biotechnological applications

2021 ◽  
Vol 37 (4) ◽  
Author(s):  
May L. K. Khider ◽  
Trygve Brautaset ◽  
Marta Irla
Keyword(s):  
Animal Feed ◽  
Bacterial Species ◽  
Carbon Sources ◽  
Value Added ◽  
Anthropogenic Pollution ◽  
Functional Expression ◽  
Ongoing Research ◽  
Microbial Cell Factories ◽  
Cell Factories ◽  
Food Market

AbstractWorldwide, the use of methane is limited to generating power, electricity, heating, and for production of chemicals. We believe this valuable gas can be employed more widely. Here we review the possibility of using methane as a feedstock for biotechnological processes based on the application of synthetic methanotrophs. Methane monooxygenase (MMO) enables aerobic methanotrophs to utilize methane as a sole carbon and energy source, in contrast to industrial microorganisms that grow on carbon sources, such as sugar cane, which directly compete with the food market. However, naturally occurring methanotrophs have proven to be difficult to manipulate genetically and their current industrial use is limited to generating animal feed biomass. Shifting the focus from genetic engineering of methanotrophs, towards introducing metabolic pathways for methane utilization in familiar industrial microorganisms, may lead to construction of efficient and economically feasible microbial cell factories. The applications of a technology for MMO production are not limited to methane-based industrial synthesis of fuels and value-added products, but are also of interest in bioremediation where mitigating anthropogenic pollution is an increasingly relevant issue. Published research on successful functional expression of MMO does not exist, but several attempts provide promising future perspectives and a few recent patents indicate that there is an ongoing research in this field. Combining the knowledge on genetics and metabolism of methanotrophy with tools for functional heterologous expression of MMO-encoding genes in non-methanotrophic bacterial species, is a key step for construction of synthetic methanotrophs that holds a great biotechnological potential.

scholarly journals Bioprospecting of microbial strains for biofuel production: metabolic engineering, applications, and challenges

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Mobolaji Felicia Adegboye ◽  
Omena Bernard Ojuederie ◽  
Paola M. Talia ◽  
Olubukola Oluranti Babalola
Keyword(s):  
Metabolic Engineering ◽  
Lignocellulosic Biomass ◽  
Metabolic Pathways ◽  
Biofuel Production ◽  
Advanced Technology ◽  
Biological Degradation ◽  
Microbial Cell Factories ◽  
Cell Factories ◽  
Inhibitory Compounds ◽  
Wide Range

AbstractThe issues of global warming, coupled with fossil fuel depletion, have undoubtedly led to renewed interest in other sources of commercial fuels. The search for renewable fuels has motivated research into the biological degradation of lignocellulosic biomass feedstock to produce biofuels such as bioethanol, biodiesel, and biohydrogen. The model strain for biofuel production needs the capability to utilize a high amount of substrate, transportation of sugar through fast and deregulated pathways, ability to tolerate inhibitory compounds and end products, and increased metabolic fluxes to produce an improved fermentation product. Engineering microbes might be a great approach to produce biofuel from lignocellulosic biomass by exploiting metabolic pathways economically. Metabolic engineering is an advanced technology for the construction of highly effective microbial cell factories and a key component for the next-generation bioeconomy. It has been extensively used to redirect the biosynthetic pathway to produce desired products in several native or engineered hosts. A wide range of novel compounds has been manufactured through engineering metabolic pathways or endogenous metabolism optimizations by metabolic engineers. This review is focused on the potential utilization of engineered strains to produce biofuel and gives prospects for improvement in metabolic engineering for new strain development using advanced technologies.

Sign in / Sign up

Export Citation Format

Share Document