Advances in Engineering Nucleotide Sugar Metabolism for Natural Product Glycosylation in .

Glycosylation is a ubiquitous modification present across all of biology, affecting many things such as physicochemical properties, cellular recognition, subcellular localization, and immunogenicity. Nucleotide sugars are important precursors needed to study glycosylation and produce glycosylated products. is a potentially powerful platform for producing glycosylated biomolecules, but it lacks nucleotide sugar diversity.

Complete biosynthesis of QS-21 in engineered yeast.

QS-21 is a potent vaccine adjuvant and remains the only saponin-based adjuvant that has been clinically approved for use in humans. However, owing to the complex structure of QS-21, its availability is limited. Today, the supply depends on laborious extraction from the Chilean soapbark tree or on low-yielding total chemical synthesis.

Engineered as a Biosynthetic Platform of Nucleotide Sugars.

Glycosylation of biomolecules can greatly alter their physicochemical properties, cellular recognition, subcellular localization, and immunogenicity. Glycosylation reactions rely on the stepwise addition of sugars using nucleotide diphosphate (NDP)-sugars. Making these substrates readily available will greatly accelerate the characterization of new glycosylation reactions, elucidation of their underlying regulation mechanisms, and production of glycosylated molecules.

Production of polyhydroxyalkanoates by engineered Halomonas bluephagenesis using starch as a carbon source.

A novel α-amylase Amy03713 was screened and cloned from the starch utilization strain Vibrio alginolyticus LHF01. When heterologously expressed in Escherichia coli, Amy03713 exhibited the highest enzyme activity at 45 °C and pH 7, maintained >50 % of the enzyme activity in the range of 25-75 °C and pH 5-9, and sustained >80 % of the enzyme activity in 25 % (w/v) of NaCl solution, thus showing a wide range of adapted temperatures, pH, and salt concentrations. Halomonas bluephagenesis harboring amy03713 gene was able to directly utilize starch.

Complete biosynthesis of the potent vaccine adjuvant QS-21.

QS-21 is a potent vaccine adjuvant currently sourced by extraction from the Chilean soapbark tree. It is a key component of human vaccines for shingles, malaria, coronavirus disease 2019 and others under development. The structure of QS-21 consists of a glycosylated triterpene scaffold coupled to a complex glycosylated 18-carbon acyl chain that is critical for immunostimulant activity.

Development of Corynebacterium glutamicum as a monoterpene production platform.

Monoterpenes are commonly known for their role in the flavors and fragrances industry and are also gaining attention for other uses like insect repellant and as potential renewable fuels for aviation. Corynebacterium glutamicum, a Generally Recognized as Safe microbe, has been a choice organism in industry for the annual million ton-scale bioproduction of amino acids for more than 50 years; however, efforts to produce monoterpenes in C. glutamicum have remained relatively limited.

Deciphering triterpenoid saponin biosynthesis by leveraging transcriptome response to methyl jasmonate elicitation in Saponaria vaccaria.

Methyl jasmonate (MeJA) is a known elicitor of plant specialized metabolism, including triterpenoid saponins. Saponaria vaccaria is an annual herb used in traditional Chinese medicine, containing large quantities of oleanane-type triterpenoid saponins with anticancer properties and structural similarities to the vaccine adjuvant QS-21. Leveraging the MeJA-elicited saponin biosynthesis, we identify multiple enzymes catalyzing the oxidation and glycosylation of triterpenoids in S.

Arsenic pollution, geochemical fractions, and leaching characteristics in soil samples from four contaminated sites in the Beijiang River Basin, South China.

To remediate historically polluted sites before their land-use changes, it is essential to understand the concentration distribution, geochemical fraction, and migratory behavior of As in soil with varied particle sizes for the use of a sieving procedure. This study investigated the amount and percentage of As in soil with different particle sizes (0.25, 0.

Improved polyketide production in C. glutamicum by preventing propionate-induced growth inhibition.

Corynebacterium glutamicum is a promising host for production of valuable polyketides. Propionate addition, a strategy known to increase polyketide production by increasing intracellular methylmalonyl-CoA availability, causes growth inhibition in C. glutamicum.

Expanding Extender Substrate Selection for Unnatural Polyketide Biosynthesis by Acyltransferase Domain Exchange within a Modular Polyketide Synthase.

Modular polyketide synthases (PKSs) are polymerases that employ α-carboxyacyl-CoAs as extender substrates. This enzyme family contains several catalytic modules, where each module is responsible for a single round of polyketide chain extension. Although PKS modules typically use malonyl-CoA or methylmalonyl-CoA for chain elongation, many other malonyl-CoA analogues are used to diversify polyketide structures in nature.

Microbial production of high octane and high sensitivity olefinic ester biofuels.

Background: Advanced spark ignition engines require high performance fuels with improved resistance to autoignition. Biologically derived olefinic alcohols have arisen as promising blendstock candidates due to favorable octane numbers and synergistic blending characteristics. However, production and downstream separation of these alcohols are limited by their intrinsic toxicity and high aqueous solubility, respectively.

Sex Difference in Emotion Recognition under Sleep Deprivation: Evidence from EEG and Eye-tracking.

Many psychiatric disorders are accompanied with sleep abnormalities, having significant influence on emotions which might worsen the disorder conditions. Previous studies discovered that the emotion recognition task with objective physiological signals, such as electroencephalography (EEG) and eye movements, provides a reliable way to figure out the complicated relationship between emotion and sleep. However, both of the emotion and EEG signals are affected by sex.

A Novel Experiment Setting for Cross-subject Emotion Recognition.

Recently, cross-subject emotion recognition attracts widespread attention. The current emotional experiments mainly use video clips of different emotions as stimulus materials, but the videos watched by different subjects are the same, which may introduce the same noise pattern in the collected data. However, the traditional experiment settings for cross-subject emotion recognition models couldn't eliminate the impact of same video clips on recognition results, which may lead to a bias on classification.

Determination of butyrylcholinesterase activity based on thiamine luminescence modulated by MnO nanosheets.

In this paper, a novel strategy for biosensing butyrylcholinesterase (BChE) activity is developed based on manganese dioxide (MnO) nanosheets to modulate the photoluminescence of thiamine (TH). The oxidase-like activity of MnO nanosheets enables them to catalyze the oxidation of non-fluorescent substrate TH to generate strong fluorescent thiochrome (TC). When the target BChE is introduced to form thiocholine in the presence of S-butyrylthiocholine iodide (BTCh), MnO nanosheets are reduced by thiocholine to Mn, resulting in the loss of their oxidase-like activity and the reduction of TC fluorescence.

Genome-scale metabolic rewiring improves titers rates and yields of the non-native product indigoidine at scale.

High titer, rate, yield (TRY), and scalability are challenging metrics to achieve due to trade-offs between carbon use for growth and production. To achieve these metrics, we take the minimal cut set (MCS) approach that predicts metabolic reactions for elimination to couple metabolite production strongly with growth. We compute MCS solution-sets for a non-native product indigoidine, a sustainable pigment, in Pseudomonas putida KT2440, an emerging industrial microbe.

Fatty Acid and Alcohol Metabolism in Pseudomonas putida: Functional Analysis Using Random Barcode Transposon Sequencing.

With its ability to catabolize a wide variety of carbon sources and a growing engineering toolkit, KT2440 is emerging as an important chassis organism for metabolic engineering. Despite advances in our understanding of the organism, many gaps remain in our knowledge of the genetic basis of its metabolic capabilities. The gaps are particularly noticeable in our understanding of both fatty acid and alcohol catabolism, where many paralogs putatively coding for similar enzymes coexist, making biochemical assignment via sequence homology difficult.

Movement speed effects on beta-band oscillations in sensorimotor cortex during voluntary activity.

Beta-band oscillations are a dominant feature in the sensorimotor system, which includes movement-related beta desynchronization (MRBD) during the preparation and execution phases of movement and postmovement beta synchronization (PMBS) on movement cessation. Many studies have linked this rhythm to motor functions. However, its associations to the movement speed are still unclear.

An iron (II) dependent oxygenase performs the last missing step of plant lysine catabolism.

Despite intensive study, plant lysine catabolism beyond the 2-oxoadipate (2OA) intermediate remains unvalidated. Recently we described a missing step in the D-lysine catabolism of Pseudomonas putida in which 2OA is converted to D-2-hydroxyglutarate (2HG) via hydroxyglutarate synthase (HglS), a DUF1338 family protein. Here we solve the structure of HglS to 1.

DDX11-AS1exacerbates bladder cancer progression by enhancing CDK6 expression via suppressing miR-499b-5p.

Purpose: We investigated DDX11-AS1 effects on bladder cancer (BLCA) progression to identify a new potential therapeutic target for BLCA.

Methods: BLCA cases (n = 108) were enrolled. SW780 and J82 cells were transfected.

Leveraging host metabolism for bisdemethoxycurcumin production in .

is a saprophytic bacterium with robust metabolisms and strong solvent tolerance making it an attractive host for metabolic engineering and bioremediation. Due to its diverse carbon metabolisms, its genome encodes an array of proteins and enzymes that can be readily applied to produce valuable products. In this work we sought to identify design principles and bottlenecks in the production of type III polyketide synthase (T3PKS)-derived compounds in .

Coordinative Alignment in the Pores of MOFs for the Structural Determination of N-, S-, and P-Containing Organic Compounds Including Complex Chiral Molecules.

Coordinative alignment of target small molecules onto a chiral metal-organic framework (MOF-520)provides a powerful method to determine the structures of small molecules through single-crystal X-ray diffraction (SXRD). In this work, the structures of 17 molecules with eight new coordinating functionalities and varying size have been determined by this method, four of which are complex molecules being crystallized for the first time. The chirality of the MOF backbone not only enables enantioselective crystallization of chiral small molecules from a racemic mixture but also imposes diastereoselective incorporation upon achiral molecules.