Article
Refine
Year of publication
Institute
- Fachbereich Chemie und Biotechnologie (473) (remove)
Language
- English (473) (remove)
Document Type
- Article (473) (remove)
Keywords
- Heparin (3)
- Bacillaceae (2)
- Biotechnological application (2)
- Butanol (2)
- Chemometrics (2)
- IR spectroscopy (2)
- NMR spectroscopy (2)
- Principal component analysis (2)
- Standardization (2)
- Subtilases (2)
- Subtilisin (2)
- bubble column (2)
- methanation (2)
- plug flow reactor (2)
- qNMR (2)
- (Poly)saccharides (1)
- ABE (1)
- Acid crash (1)
- Algal Turf Scrubber (1)
- Algal–bacterial bioflm (1)
- Alginate beads (1)
- Alkalihalobacillus okhensis (1)
- Aloe vera (1)
- Authenticity (1)
- Biofuel (1)
- Biogas (1)
- Biological hydrogen (1)
- Biomass (1)
- Biorefinery (1)
- Bragg peak (1)
- Broad pH spectrum (1)
- C. acetobutylicum (1)
- CRISPR/Cas9 (1)
- Carrier solvents (1)
- Chondroitin sulfate (1)
- Circular bioeconomy (1)
- Clostridium acetobutylicum (1)
- Crude heparin (1)
- Cyclotron production (1)
- Dark fermentation (1)
- Dehydrogenase (1)
- Detergent protease (1)
- Deuterated solvents (1)
- Deuterium NMR (1)
- Diaphorase (1)
- Dietary supplements (1)
- Electronic cigarettes (1)
- Enzymatic biosensor (1)
- Extracellular enzymes (1)
- Free-base nicotine (1)
- Ga-68 (1)
- Glucosamine (1)
- Halotolerant protease (1)
- High-field NMR (1)
- Hydrolysis (1)
- Hypersecretion (1)
- IR (1)
- Inorganic ions (1)
- Ions (1)
- Lignocellulose (1)
- Linear discriminant analysis (1)
- Low field NMR (1)
- Manufacturer (1)
- Marker-free mutagenesis (1)
- Medical radionuclide production (1)
- Metabolic shift (1)
- Metal contaminants (1)
- Methane (1)
- Microfluidic solvent extraction (1)
- Molecular modelling (1)
- Molecular weight determination (1)
- NMR (1)
- Organic acids (1)
- Organic waste (1)
- P2G (1)
- PLS-regression (1)
- Polysaccharides (1)
- Pre-culture (1)
- Pretreatment (1)
- Quality control (1)
- Quantum chemistry (1)
- Simultaneous determination (1)
- Soft independent modeling of class analogy (1)
- Spectroscopy (1)
- Stenotrophomonas maltophilia (1)
- Streptomyces griseus (1)
- Streptomyces lividans (1)
- USP (1)
- Uracil-phosphoribosyltransferase (1)
- Weak organic acids (1)
- acetoin (1)
- acetoin reductase (1)
- actuator-sensor system (1)
- alcoholic beverages (1)
- aspergillus (1)
- bacterial cellulose (1)
- bi-enzyme biosensor (1)
- bio-methane (1)
- bioavailability (1)
- biodegradable polymers (1)
- biological dosimeter (1)
- biomethane (1)
- biosensors (1)
- borehole disposal (1)
- capacitive field-effect sensor (1)
- capacitive field-effect sensors (1)
- coculture (1)
- deficit irrigation (1)
- detergent protease (1)
- disposal facility (1)
- drug metabolising enzymes (1)
- drug–drug interactions (1)
- elastomers (1)
- enzyme kinetics (1)
- enzyme-logic gate (1)
- exopolysaccharides (1)
- fatty acid (1)
- filamentous fungi (1)
- genome engineering (1)
- geological disposal (1)
- glycine (1)
- halotolerant protease (1)
- high-alkaline subtilisin (1)
- human metabolites (1)
- hydrogel (1)
- hydrogels (1)
- light-addressable electrode (1)
- light-addressable potentiometric sensor (1)
- mechanical properties (1)
- metathesis (1)
- microfluidics (1)
- micronutrients (1)
- neutrons (1)
- nuclear waste (1)
- onion (1)
- optical fibers (1)
- oxidative stable protease (1)
- penicillinase (1)
- polyamide (1)
- polyaspartic acid (1)
- polyester (1)
- power-to-gas (1)
- prebiotic (1)
- proton therapy (1)
- protons (1)
- pullulan (1)
- recombinant expression (1)
- relative dosimetry (1)
- renewable resources (1)
- retention time (1)
- rubber (1)
- superabsorbent polymers (1)
- supramolecular structures (1)
- swelling properties (1)
- theory and modeling (1)
- tobacco mosaic virus (TMV) (1)
- transporters (1)
- urease (1)
- water economy (1)
- yield (1)
- α-aminoacylase (1)
- ε-lysine acylase (1)
An enzyme-based multi-parameter biosensor is developed for monitoring the concentration of formate, d-lactate, and l-lactate in biological samples. The sensor is based on the specific dehydrogenation by an oxidized β-nicotinamide adenine dinucleotide (NAD+)-dependent dehydrogenase (formate dehydrogenase, d-lactic dehydrogenase, and l-lactic dehydrogenase, respectively) in combination with a diaphorase from Clostridium kluyveri (EC 1.8.1.4). The enzymes are immobilized on a platinum working electrode by cross-linking with glutaraldehyde (GA). The principle of the determination scheme in case of l-lactate is as follows: l-lactic dehydrogenase (l-LDH) converts l-lactate into pyruvate by reaction with NAD+. In the presence of hexacyanoferrate(III), the resulting reduced β-nicotinamide adenine dinucleotide (NADH) is then regenerated enzymatically by diaphorase. The electrochemical detection is based on the current generated by oxidation of hexacyanoferrate(II) at an applied potential of +0.3 V vs. an Ag/AgCl reference electrode. The biosensor will be electrochemically characterized in terms of linear working range and sensitivity. Additionally, the successful practical application of the sensor is demonstrated in an extract from maize silage.
Cupriavidus necator H16 gains increasing attention in microbial research and biotechnological application due to its diverse metabolic features. Here we present a tightly controlled gene expression system for C. necator including the pBBR1-vector that contains hybrid promoters originating from C. necator native tolC-promoter in combination with a synthetic tetO-operator. The expression of the reporter gene from these plasmids relies on the addition of the exogenous inducer doxycycline (dc). The novel expression system offers a combination of advantageous features as; (i) high and dose-dependent recombinant protein production, (ii) tight control with a high dynamic range (On/Off ratio), which makes it applicable for harmful pathways or for toxic protein production, (iii) comparable cheap inducer (doxycycline, dc), (iv) effective at low inducer concentration, that makes it useful for large scale application, (v) rapid, diffusion controlled induction, and (vi) the inducer does not interfere within the cell metabolism. As applications of the expression system in C. necator H16, the growth ability on glycerol was enhanced by constitutively expressing the E. coli glpk gene-encoding for glycerol kinase. Likewise, we used the system to overcome the expression toxicity of mevalonate pathway in C. necator H16. With this system, the mevalonate-genes were successfully introduced in the host and the recombinant strains could produce about 200 mg/l mevalonate.
Three amperometric biosensors have been developed for the detection of L-malic acid, fumaric acid, and L -aspartic acid, all based on the combination of a malate-specific dehydrogenase (MDH, EC 1.1.1.37) and diaphorase (DIA, EC 1.8.1.4). The stepwise expansion of the malate platform with the enzymes fumarate hydratase (FH, EC 4.2.1.2) and aspartate ammonia-lyase (ASPA, EC 4.3.1.1) resulted in multi-enzyme reaction cascades and, thus, augmentation of the substrate spectrum of the sensors. Electrochemical measurements were carried out in presence of the cofactor β-nicotinamide adenine dinucleotide (NAD+) and the redox mediator hexacyanoferrate (III) (HCFIII). The amperometric detection is mediated by oxidation of hexacyanoferrate (II) (HCFII) at an applied potential of + 0.3 V vs. Ag/AgCl. For each biosensor, optimum working conditions were defined by adjustment of cofactor concentrations, buffer pH, and immobilization procedure. Under these improved conditions, amperometric responses were linear up to 3.0 mM for L-malate and fumarate, respectively, with a corresponding sensitivity of 0.7 μA mM−1 (L-malate biosensor) and 0.4 μA mM−1 (fumarate biosensor). The L-aspartate detection system displayed a linear range of 1.0–10.0 mM with a sensitivity of 0.09 μA mM−1. The sensor characteristics suggest that the developed platform provides a promising method for the detection and differentiation of the three substrates.
The objective of this study is the establishment of a differential scanning calorimetry (DSC) based method for online analysis of the biodegradation of polymers in complex environments. Structural changes during biodegradation, such as an increase in brittleness or crystallinity, can be detected by carefully observing characteristic changes in DSC profiles. Until now, DSC profiles have not been used to draw quantitative conclusions about biodegradation. A new method is presented for quantifying the biodegradation using DSC data, whereby the results were validated using two reference methods.
The proposed method is applied to evaluate the biodegradation of three polymeric biomaterials: polyhydroxybutyrate (PHB), cellulose acetate (CA) and Organosolv lignin. The method is suitable for the precise quantification of the biodegradability of PHB. For CA and lignin, conclusions regarding their biodegradation can be drawn with lower resolutions. The proposed method is also able to quantify the biodegradation of blends or composite materials, which differentiates it from commonly used degradation detection methods.
Differentiation between Phaeocystis pouchetii (Har.) Lagerheim and Phaeocystis globosa Scherffel
(1987)