Multisite Mutation of the cAMP Receptor Protein: Enhancing Xylitol Biosynthesis by Activating Xylose Catabolism and Improving Strain Tolerance.

The bioproduction of xylitol from hemicellulose hydrolysate has good potential for industrial development. However, xylitol productivity has always been limited due to corncob hydrolysate toxicity and glucose catabolic repression. To address these challenges, this work selected the S83 and S128 amino acid residues of the cyclic AMP receptor protein (CRP) as the modification target.

Production of red yeast rice rich in monacolin K by variable temperature solid fermentation of .

Hypercholesterolemia represents a serious public health problem as it significantly increases the risk of developing cardiovascular diseases. Monacolin K (MK) in red yeast rice is an active compound that can effectively lower plasma cholesterol. To enhance the yield of MK in solid state fermentation of HNU01, the effects of different variables were systematically examined in single-factor experiments.

Engineered Biosynthesis through the Adenylation Domains from Nonribosomal Peptide Synthetases.

Nonribosomal peptide synthetases, consisted of multiple catalytic domains, are involved in the biosynthesis of an important family of bioactive natural products in a coordinated manner. Among the functional domains, adenylation domains are specifically responsible for recognizing carboxylic acid building blocks and synthesizing aminoacyl adenylates. Given their critical roles in the biosynthesis of the growing peptide, A-domains are also referred to as the "gatekeeper".

Genetically Engineering to Produce Xylitol from Corncob Hydrolysate without Lime Detoxification.

Before fermentation with hemicellulosic hydrolysate as a substrate, it is generally necessary to detoxify the toxic substances that are harmful to microorganism growth. Cyclic AMP receptor protein (CRP) is a global regulator, and mutation of its key sites may have an important impact on virulence tolerance. Using corncob hydrolysate without ion-exchange or lime detoxification as the substrate, shake flask fermentation experiments showed that CRP mutant IS5-dG (I112L, T127G, A144T) produced 18.

Advances in Research at Synthesis Process Optimization and Quality Standard Improvement of -desmethylvenlafaxine Succinate.

We herein describe an optimal approach for the efficient synthesis of -desmethylvenlafaxine succinate monohydrate (DVS) with high yield and high purity through 5-step reactions, including benzyl protection of the phenolic hydroxyl group, cyclohexanone condensation, deprotection, cyano reduction, dimethylation, and succinic acid salt formation from -hydroxybenzene acetonitrile as a starting material. 4-Benzyloxyphenylacetonitrile (Intermediate I) was prepared by the hydroxyl protection of the bromide benzyl--hydroxyphenylacetonitrile catalyzed by potassium carbonate with 99.83% purity and 98.

Metabolic Behaviors of Aconitum Alkaloids in Different Concentrations of and Effects of Aconitine in Healthy Human and Long QT Syndrome Cardiomyocytes.

Aconiti Lateralis Radix Praeparata () is the processed lateral root of Debx, which is widely used in emergency clinics. Poisoning incidents and adverse reactions occur with the improper intake of Metabolic characteristics of aconitum alkaloids of may vary, and the effects of in healthy and Long QT syndrome (LQTS) patients is unknown. In this experiment, 24 Sprague Dawley rats were randomly divided into three groups: 2.

Photo-Responsive Micelles with Controllable and Co-Release of Carbon Monoxide, Formaldehyde and Doxorubicin.

Endogenous gases have attracted much attention due to their potent applications in disease therapies. The combined therapy, including gaseous molecules and other medicines that can create synergistic effects, is a new way for future treatment. However, due to the gaseous state, gas utilization in medical service is still limited.

Preparation of calcium carbonate microrods from the gypsum scale layer of evaporation equipment.

The difficult-to-remove CaSO scale layer attached to an evaporator wall is a major problem in related industries. How to efficiently remove the CaSO scale layer and convert it into fine chemicals with high added value, so as to turn waste into treasure, is a current research hotspot. In this study, a CaSO scale layer was removed by 15 min rotary washing a phase transfer route.

Increasing NADPH Availability for Xylitol Production via Pentose-Phosphate-Pathway Gene Overexpression and Embden-Meyerhof-Parnas-Pathway Gene Deletion in .

Cofactor availability is often a rate-limiting factor in the bioconversion of xylose to xylitol. The overexpression of pentose phosphate pathway genes and the deletion of Embden-Meyerhof-Parnas pathway genes can modulate the glucose metabolic flux and increase the intracellular NADPH supply, enabling cells to produce xylitol from corncob hydrolysates. The effects of and/or overexpression and , , and/or deletion on the intracellular redox environment and xylitol production were examined.

Combination of the CRP mutation and ptsG deletion in Escherichia coli to efficiently synthesize xylitol from corncob hydrolysates.

The biotechnology-based production of xylitol has received widespread attention because it can use cheap and renewable lignocellulose as a raw material, thereby decreasing costs and pollution. The simultaneous use of various sugars in lignocellulose hydrolysates is a primary prerequisite for efficient xylitol production. In this study, a ΔptsG and crp* combinatorial strategy was used to generate Escherichia coli W3110 strain IS5-dI, which completely eliminated glucose repression and simultaneously used glucose and xylose.

Efficient production of xylitol by the integration of multiple copies of xylose reductase gene and the deletion of Embden-Meyerhof-Parnas pathway-associated genes to enhance NADPH regeneration in Escherichia coli.

Cofactor supply is a rate-limiting step in the bioconversion of xylose to xylitol. Strain WZ04 was first constructed by a novel simultaneous deletion-insertion strategy, replacing ptsG, xylAB and ptsF in wild-type Escherichia coli W3110 with three mutated xylose reductase genes (xr) from Neurospora crassa. Then, the pfkA, pfkB, pgi and/or sthA genes were deleted and replaced by xr to investigate the influence of carbon flux toward the pentose phosphate pathway and/or transhydrogenase activity on NADPH generation.

The advancement of multidimensional QSAR for novel drug discovery - where are we headed?

The Multidimensional quantitative structure-activity relationship (multidimensional-QSAR) method is one of the most popular computational methods employed to predict interesting biochemical properties of existing or hypothetical molecules. With continuous progress, the QSAR method has made remarkable success in various fields, such as medicinal chemistry, material science and predictive toxicology. Areas covered: In this review, the authors cover the basic elements of multidimensional -QSAR including model construction, validation and application.