The complete degradation of 1,2-dichloroethane in Escherichia coli by metabolic engineering.

1,2-Dichloroethane (1,2-DCA), a widely utilized chemical intermediate and organic solvent in industry, frequently enters the environment due to accidental leaks and mishandling during application processes. Thus, the in-situ remediation of contaminated sites has become increasingly urgent. However, traditional remediation methods are inefficient and costly, while bioremediation presents a green, efficient, and non-secondary polluting alternative.

Biosynthesis of melatonin from L-tryptophan by an engineered microbial cell factory.

Background: The demand for melatonin is increasing due to its health-promoting bioactivities such as antioxidant and sleep benefits. Although melatonin is present in various organisms, its low content and high extraction cost make it unsustainable. Biosynthesis is a promising alternative method for melatonin production.

Creation of Environmentally Friendly Super "Dinitrotoluene Scavenger" Plants.

Pervasive environmental contamination due to the uncontrolled dispersal of 2,4-dinitrotoluene (2,4-DNT) represents a substantial global health risk, demanding urgent intervention for the removal of this detrimental compound from affected sites and the promotion of ecological restoration. Conventional methodologies, however, are energy-intensive, susceptible to secondary pollution, and may inadvertently increase carbon emissions. In this study, a 2,4-DNT degradation module is designed, assembled, and validated in rice plants.

Metabolic engineering of Escherichia coli for 2,4-dinitrotoluene degradation.

2,4-Dinitrotoluene (2,4-DNT) as a common industrial waste has been massively discharged into the environment with industrial wastewater. Due to its refractory degradation, high toxicity, and bioaccumulation, 2,4-DNT pollution has become increasingly serious. Compared with the currently available physical and chemical methods, in situ bioremediation is considered as an economical and environmentally friendly approach to remove toxic compounds from contaminated environment.

Metabolic engineering for the biosynthesis of bis-indolylquinone terrequinone A in Escherichia coli from L-tryptophan and prenol.

Background: Terrequinone A is a bis-indolylquinone natural product with antitumor activity. Due to its unique asymmetric quinone core structure and multiple functional groups, biosynthesis is more efficient and environmentally friendly than traditional chemical synthesis. Currently, most bis-indolylquinones are obtained by direct extraction from fungi or by chemical synthesis.

Genetic engineering of complex feed enzymes into barley seed for direct utilization in animal feedstuff.

Currently, feed enzymes are primarily obtained through fermentation of fungi, bacteria, and other microorganisms. Although the manufacturing technology for feed enzymes has evolved rapidly, the activities of these enzymes decline during the granulating process and the cost of application has increased over time. An alternative approach is the use of genetically modified plants containing complex feed enzymes for direct utilization in animal feedstuff.

ElNFS1, a nitroreductase gene from Enterobacter ludwigii, confers enhanced detoxification and phytoremediation of 4-nitrobenzaldehyde in rice.

4-nitrobenzaldehyde (4-NBA) is a widely used chemical intermediate for industrial application and an important photodegradation product of chloramphenicol. This compound represents a substantial threat to human health and ecosystem due to its genotoxic and mutagenic effect. In this study, the 4-NBA detoxification by transgenic rice overexpressing a bacterial nitroreductase gene, ElNFS1, from Enterobacter ludwigii were investigated.

Construction of complete degradation pathway for nitrobenzene in Escherichia coli.

Nitrobenzene is widely present in industrial wastewater and soil. Biodegradation has become an ideal method to remediate organic pollutants due to its low cost, high efficiency, and absence of secondary pollution. In the present study, 10 exogenous genes that can completely degrade nitrobenzene were introduced into Escherichia coli, and their successful expression in the strain was verified by fluorescence quantitative polymerase chain reaction and proteomic analysis.

Metabolic engineering of Escherichia coli for direct production of vitamin C from D-glucose.

Background: Production of vitamin C has been traditionally based on the Reichstein process and the two-step process. However, the two processes share a common disadvantage: vitamin C cannot be directly synthesized from D-glucose. Therefore, significant effort has been made to develop a one-step vitamin C fermentation process.

Rice carotenoid biofortification and yield improvement conferred by endosperm-specific overexpression of .

Carotenoids, indispensable isoprenoid phytonutrients, are synthesized in plastids and are known to be deficient in rice endosperm. Many studies, involving transgenic manipulations of carotenoid biosynthetic genes, have been performed to obtain carotenoid-enriched rice grains. Nuclear-encoded GOLDEN2-LIKE (GLK) transcription factors play important roles in the regulation of plastid and thylakoid grana development.

Enhanced phytoremediation of selenium using genetically engineered rice plants.

Selenium (Se) is a micronutrient essential for human and animal health. However, Se is toxic at high levels because the nonspecific substitution of cysteine by selenocysteine could lead to protein malfunction. In an attempt to prevent nonspecific selenocysteine incorporation into proteins, we simultaneously overexpressed the gene encoding selenocysteine lyase from Homo sapiens (HsSL), which specifically catalyzes the decomposition of selenocysteine into elemental Se and alanine, and the gene encoding selenocysteine methyltransferase from Astragalus bisulcatus (AbSMT), which methylates selenocysteine into methylselenocysteine in rice.

Metabolic engineering of Oryza sativa for complete biodegradation of thiocyanate.

Industrial thiocyanate (SCN) waste streams from gold mining and coal coking have caused serious environmental pollution worldwide. Phytoremediation is an efficient technology in treating hazardous wastes from the environment. However, the phytoremediation efficiency of thiocyanate is very low due to the fact that plants lack thiocyanate degradation enzymes.

Biodegradation of p-nitrophenol by engineered strain.

p-Nitrophenol (PNP) is an important environmental pollutant and can causes significant environmental and health risks. Compared with the traditional methods, biodegradation is a useful one to completely remove the harmful pollutants from the environment. Here, an engineered strain was first constructed by introducing PNP biodegradation pathway via the hydroquinone (HQ) pathway into Escherichia coli.

Enhanced phytoremediation of TNT and cobalt co-contaminated soil by AfSSB transformed plant.

2,4,6-trinitrotoluene (TNT) and cobalt (Co) contaminants have posed a severe environmental problem in many countries. Phytoremediation is an environmentally friendly technology for the remediation of these contaminants. However, the toxicity of TNT and cobalt limit the efficacy of phytoremediation application.

The intestinal microbial community dissimilarity in hepatitis B virus-related liver cirrhosis patients with and without at alcohol consumption.

Background: Chronic hepatitis B virus (HBV) infection-reduced liver functions are associated with intestinal microbial community dissimilarity. This study aimed to investigate the microbial community dissimilarity in patients with different grades of HBV-related liver cirrhosis.

Results: Serum endotoxin was increased with Child-Pugh (CP) class (A, B, and C).

Fermentation Process and Metabolic Flux of Ethanol Production from the Detoxified Hydrolyzate of Cassava Residue.

With the growth of the world population, energy problems are becoming increasingly severe; therefore, sustainable energy sources have gained enormous importance. With respect to ethanol fuel production, biomass is gradually replacing grain as the main raw material. In this study, we explored the fermentation of five- and six-carbon sugars, the main biomass degradation products, into alcohol.

Production of Fumaric Acid by Bioconversion of Corncob Hydrolytes Using an Improved Rhizopus oryzae Strain.

The use of microorganism fermentation for production of fumaric acid (FA), which is widely used in food, medicine, and other fields, can provide technical support for the FA industry. In this study, we aimed to increase the titer of FA production by using an improved Rhizopus oryzae WHT5, which was domesticated to obtain a furfural-resistant strain in corncob hydrolytes. The metabolic pathways and metabolic network of this strain were investigated, and the related enzymes and metabolic flux were analyzed.

Production of itaconic acid by biotransformation of wheat bran hydrolysate with Aspergillus terreus CICC40205 mutant.

The replacement of the carbon source in the microbial production of itaconic acid (IA) with economic alternatives has attracted significant attention. In this study, an Aspergillus terreus CICC40205 mutant was used to increase the IA titer and decrease the citric acid titer in the wheat bran hydrolysate compared with the parental strain. The results showed that the IA titer was increased by 33.

[Clinical efficacy of various antiviral-based strategies to treat chronic hepatitis patients with positivity for hepatitis B e antigen and rtN236T mutation].

Objective: To compare the efficacy and safety of the common antivirals, including adefovir dipivoxil (ADV), pegylated-interferon alpha-2a (peg-IFN) and lamivudine (LAM), used as combination therapies to treat chronic hepatitis B (CHB) patients with positivity for the hepatitis B e antigen (HBeAg) and hepatitis B virus (HBV) harboring the ADV-resistance mutation, rtN236T, and to explore the factors associated with curative outcome.

Methods: Sixty-five adult CHB patients (age range: 20-60 years) who were unresponsive to ADV therapy (HBeAg-positive; HBV DNA >or= 10(5) copies/ml), LAM-naive, and tested positive for the rtN236T HBV mutation were enrolled in the study and randomly divided into two treatment groups: Group A (n = 33), who were administered ADV (10 mg/day, orally) plus peg-IFN (180 microg/week, subcutaneous injection) for 48 weeks; and Group B (n = 32 patients), who received the ADV plus LAM (100 mg/day, orally) for 48 weeks followed by continued LAM treatment for an additional 24 weeks. Pre- (baseline), during and post-treatment measurements of HBV viral loads and hepatitis B markers were made by quantitative PCR and electrochemiluminescence assays, respectively.