Biosynthesis of nonnutritive monosaccharide d-allulose by metabolically engineered Escherichia coli from nutritive disaccharide sucrose.

Sucrose is a commonly utilized nutritive sweetener in food and beverages due to its abundance in nature and low production costs. However, excessive intake of sucrose increases the risk of metabolic disorders, including diabetes and obesity. Therefore, there is a growing demand for the development of nonnutritive sweeteners with almost no calories.

Engineering Escherichia coli for D-allulose biosynthesis from glycerol.

D-allulose, a naturally occurring monosaccharide, is present in small quantities in nature. It is considered a valuable low-calorie sweetener due to its low absorption in the digestive tract and zero energy for growth. Most of the recent efforts to produce D-allulose have focused on in vitro enzyme catalysis.

Enhanced Biosynthesis of d-Allulose from a d-Xylose-Methanol Mixture and Its Self-Inductive Detoxification by Using Antisense RNAs in .

d-Allulose, a C-3 epimer of d-fructose, has great market potential in food, healthcare, and medicine due to its excellent biochemical and physiological properties. Microbial fermentation for d-allulose production is being developed, which contributes to cost savings and environmental protection. A novel metabolic pathway for the biosynthesis of d-allulose from a d-xylose-methanol mixture has shown potential for industrial application.

Transporter mining and metabolic engineering of Escherichia coli for high-level D-allulose production from D-fructose by thermo-swing fermentation.

D-Allulose is an ultra-low-calorie sweetener with broad market prospects in the fields of food, beverage, health care, and medicine. The fermentative synthesis of D-allulose is still under development and considered as an ideal route to replace enzymatic approaches for large-scale production of D-allulose in the future. Generally, D-allulose is synthesized from D-fructose through Izumoring epimerization.

Switching the memory behaviour from binary to ternary by triggering S relaxation in polysulfide-bearing zinc-organic complex molecular memories.

The use of crystalline metal-organic complexes with definite structures as multilevel memories can enable explicit structure-property correlations, which is significant for designing the next generation of memories. Here, four Zn-polysulfide complexes with different degrees of conjugation have been fabricated as memory devices. ZnS(L)-based memories (L = pyridine and 3-methylpyridine) can exhibit only bipolar binary memory performances, but ZnS(L)-based memories (L = 2,2'-bipyridine and 1,10-phenanthroline) illustrate non-volatile ternary memory performances with high ON2/ON1/OFF ratios (10/10/1 and 10/10/1) and ternary yields (74% and 78%).

Engineering of for D-allose fermentative synthesis from D-glucose through izumoring cascade epimerization.

D-Allose is a potential alternative to sucrose in the food industries and a useful additive for the healthcare products in the future. At present, the methods for large-scale production of D-allose are still under investigation, most of which are based on enzyme-catalyzed Izumoring epimerization. In contrast, fermentative synthesis of D-allose has never been reported, probably due to the absence of available natural microorganisms.

Methanol-Dependent Carbon Fixation for Irreversible Synthesis of d-Allulose from d-Xylose by Engineered .

d-Allulose is a rare hexose with great application potential, owing to its moderate sweetness, low energy, and unique physiological functions. The current strategies for d-allulose production, whether industrialized or under development, utilize six-carbon sugars such as d-glucose or d-fructose as a substrate and are usually based on the principle of reversible Izumoring epimerization. In this work, we designed a novel route that coupled the pathways of methanol reduction, pentose phosphate (PP), ribulose monophosphate (RuMP), and allulose monophosphate (AuMP) for to irreversibly synthesize d-allulose from d-xylose and methanol.

Metabolically Engineered for Conversion of D-Fructose to D-Allulose Phosphorylation-Dephosphorylation.

D-Allulose is an ultra-low calorie sweetener with broad market prospects. As an alternative to Izumoring, phosphorylation-dephosphorylation is a promising method for D-allulose synthesis due to its high conversion of substrate, which has been preliminarily attempted in enzymatic systems. However, phosphorylation-dephosphorylation requires polyphosphate as a phosphate donor and cannot completely deplete the substrate, which may limit its application in industry.

Intelligent self-control of carbon metabolic flux in SecY-engineered Escherichia coli for xylitol biosynthesis from xylose-glucose mixtures.

Xylitol is a salutary sugar substitute that has been widely used in the food, pharmaceutical, and chemical industries. Co-fermentation of xylose and glucose by metabolically engineered cell factories is a promising alternative to chemical hydrogenation of xylose for commercial production of xylitol. Here, we engineered a mutant of SecY protein-translocation channel (SecY [ΔP]) in xylitol-producing Escherichia coli JM109 (DE3) as a passageway for xylose uptake.

Engineering for d-Allulose Production from d-Fructose by Fermentation.

d-Allulose is considered an ideal alternative to sucrose and has shown tremendous application potential in many fields. Recently, most efforts on production of d-allulose have focused on enzyme-catalyzed epimerization of cheap hexoses. Here, we proposed an approach to efficiently produce d-allulose through fermentation using metabolically engineered JM109 (DE3), in which a SecY (ΔP) channel and a d-allulose 3-epimerase (DPEase) were co-expressed, ensuring that d-fructose could be transported in its nonphosphorylated form and then converted into d-allulose by cells.

Thermal-Responsive Polyoxometalate-Metalloviologen Hybrid: Reversible Intermolecular Three-Component Reaction and Temperature-Regulated Resistive Switching Behaviors.

The development of new-type memristors with special performance is of great interest. Herein, an inorganic-organic hybrid crystalline polyoxometalate (POM) with usual dynamic structures is reported and used as active material for fabricating memristor with unique temperature-regulated resistive switching behaviors. The hybrid POM not only exhibits tunable thermochromic properties, but also thermal-induced reversible aggregation and disaggregation reactions, leading to reversible structural transformations in SCSC fashion.

[Damage of deltamethrin on tissue and cell DNA in hepatopancreas of Pagrosomus major].

In order to study the toxic effect of deltamethrin on the hepatopancreas of Pagrosomus major with sub-acute exposure, Pagrosomus major were divided into 5 groups with different doses of semi-static exposure. The damage of the hepatopancreas tissue of Pagrosomus major was analyzed by microscopy observation and the DNA damage of the cells was analyzed by comet assay technique after 25 days exposure. The results showed that different degrees of congestion, nuclear enrichment and cell necrosis appeared in hepatopancreas of 0.

Three silver iodides with zero and one-dimensional hybrid structures directed by conjugated organic templates: synthesis and theoretical study.

Under the direction of large conjugated organic cationic SDAs (structure-directing agents), three silver(I) iodides, (ipq)4(Ag2I6 x 2I2) (1), {[pql][Ag2I3]}n (2), [(npql)2(Ag4I6)]n (3) (ipq+ = N-(isopentyl)-quinolinium, pql+ = N-propyl-quinolinium, npql+ = N-(n-pentyl)-quinolinium) have been synthesized. 1 presents a zero-dimensional structure constituting of ipq+ cations, [Ag2I6]4- anions and molecular iodine. But 2 and 3 consist of one-dimensional coordination polymers that could be described as edge-sharing AgI4 tetrahedra.