Molecularly imprinted polymers and their use in biomimetic sensors.

Molecular imprinting science and technology: a survey of the literature for the years up to and including 2003

Engineered metabolic pathways constructed from enzymes heterologous to the production host often suffer from flux imbalances, as they typically lack the regulatory mechanisms characteristic of natural metabolism. In an attempt to increase the effective concentration of each component of a pathway of interest, we built synthetic protein scaffolds that spatially recruit metabolic enzymes in a designable manner. Scaffolds bearing interaction domains from metazoan signaling proteins specifically accrue pathway enzymes tagged with their cognate peptide ligands. The natural modularity of these domains enabled us to optimize the stoichiometry of three mevalonate biosynthetic enzymes recruited to a synthetic complex and thereby achieve 77-fold improvement in product titer with low enzyme expression and reduced metabolic load. One of the same scaffolds was used to triple the yield of glucaric acid, despite high titers (0.5 g/l) without the synthetic complex. These strategies should prove generalizeable to other metabolic pathways and programmable for fine-tuning pathway flux.

Synthetic protein scaffolds provide modular control over metabolic flux

Molecular Imprinting Technology (MIT) is a technique to design artificial receptors with a predetermined selectivity and specificity for a given analyte, which can be used as ideal materials in various application fields. Molecularly Imprinted Polymers (MIPs), the polymeric matrices obtained using the imprinting technology, are robust molecular recognition elements able to mimic natural recognition entities, such as antibodies and biological receptors, useful to separate and analyze complicated samples such as biological fluids and environmental samples. The scope of this review is to provide a general overview on MIPs field discussing first general aspects in MIP preparation and then dealing with various application aspects. This review aims to outline the molecularly imprinted process and present a summary of principal application fields of molecularly imprinted polymers, focusing on chemical sensing, separation science, drug delivery and catalysis. Some significant aspects about preparation and application of the molecular imprinting polymers with examples taken from the recent literature will be discussed. Theoretical and experimental parameters for MIPs design in terms of the interaction between template and polymer functionalities will be considered and synthesis methods for the improvement of MIP recognition properties will also be presented.

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Molecularly Imprinted Polymers: Present and Future Prospective

Electrochemical sensors based on conducting polymer—polypyrrole

A sensor system for the herbicide 2,4-dichlorophenoxyacetic acid has been developed based on specific recognition of the analyte by a molecularly imprinted polymer and electrochemical detection using disposable screen-printed electrodes The method involves a competitive binding step with a nonrelated electrochemically active probe For batch binding assays, imprinted polymer particles are incubated in suspension with the analyte and the probe, followed by centrifugation and quantification of the unbound probe in the supernatant Two different compounds, namely 2,4-dichlorophenol and homogentisic acid, were tested as potential electroactive probes Both compounds could be conveniently detected by differential-pulse voltammetry on screen-printed, solvent-resistant three-electrode systems having carbon working electrodes Whereas 2,4-dichlorophenol showed very high nonspecific binding to the polymer, homogentisic acid bound specifically to the imprinted sites and thus allowed calibration curves for the anal

Imprinted polymer-based sensor system for herbicides using differential-pulse voltammetry on screen-printed electrodes.

Within the cellular framework are a number of sequentially operating enzyme systems, in many cases in the form of bi- or even multifunctional proteins each consisting of a single type of polypeptide chain but having two or more catalytic or binding functions. In order to study the properties of an artificial bifunctional enzyme, an in-frame fusion of the structural genes for β-galactosidase (lacZ) and galactokinase (galK) of Escherichia coli was made in vitro. This DNA chimaera was constructed by connecting the 3′-terminus of the lacZ gene to the 5′-terminus of the galK gene. The translated gene product was able to catalyze the sequential reaction normally carried out by the separate native enzymes.

Preparation of a Soluble Bifunctional Enzyme by Gene Fusion

Automated thermometric enzyme immunoassay of human proinsulin produced by Escherichia coli

https://febs.onlinelibrary.wiley.com/doi/pdf/10.1016/0014-5793%2887%2981325-X

The expression in E. coli of a polymeric gene coding for an esterase mimic catalyzing the hydrolysis of p-nitrophenyl esters

The combination of calorimetry and immobilized enzymes forms a pair with unique properties. Calorimetry is a general detection principle and specificity is introduced by the enzyme. We discuss here simple "semi-adiabatic' calorimeters and their application in clinical chemistry, enzyme immunoassay, process control and environmental control.

/pdf/enzyme-thermistor-analysis-in-clinical-chemistry-and-59efurnlyf.pdf

Klaus Mosbach

Papers

Imprinted polymer-based sensor system for herbicides using differential-pulse voltammetry on screen-printed electrodes.

Preparation of a Soluble Bifunctional Enzyme by Gene Fusion

Automated thermometric enzyme immunoassay of human proinsulin produced by Escherichia coli

The expression in E. coli of a polymeric gene coding for an esterase mimic catalyzing the hydrolysis of p-nitrophenyl esters

Enzyme thermistor analysis in clinical chemistry and biotechnology