Interleukin-1 and interleukin-1 antagonism.

Role of endothelium in responses of vascular smooth muscle.

Immobilization is often the key to optimizing the operational performance of an enzyme in industrial processes, particularly for use in non-aqueous media. Different methods for the immobilization of enzymes are critically reviewed. The methods are divided into three main categories, viz. (i) binding to a prefabricated support (carrier), (ii) entrapment in organic or inorganic polymer matrices, and (iii) cross-linking of enzyme molecules. Emphasis is placed on relatively recent developments, such as the use of novel supports, e.g., mesoporous silicas, hydrogels, and smart polymers, novel entrapment methods and cross-linked enzyme aggregates (CLEAs).

http://largens.com/biochemlab/peroxidase2.pdf

Enzyme immobilization: The quest for optimum performance

https://web.iitd.ac.in/~arunku/files/CEL311_Y13/Adsorption%20Theory%20to%20practice_Dabrowski.pdf

Adsorption — from theory to practice

Quantification of biological or biochemical processes are of utmost importance for medical, biological and biotechnological applications. However, converting the biological information to an easily processed electronic signal is challenging due to the complexity of connecting an electronic device directly to a biological environment. Electrochemical biosensors provide an attractive means to analyze the content of a biological sample due to the direct conversion of a biological event to an electronic signal. Over the past decades several sensing concepts and related devices have been developed. In this review, the most common traditional techniques, such as cyclic voltammetry, chronoamperometry, chronopotentiometry, impedance spectroscopy, and various field-effect transistor based methods are presented along with selected promising novel approaches, such as nanowire or magnetic nanoparticle-based biosensing. Additional measurement techniques, which have been shown useful in combination with electrochemical detection, are also summarized, such as the electrochemical versions of surface plasmon resonance, optical waveguide lightmode spectroscopy, ellipsometry, quartz crystal microbalance, and scanning probe microscopy. The signal transduction and the general performance of electrochemical sensors are often determined by the surface architectures that connect the sensing element to the biological sample at the nanometer scale. The most common surface modification techniques, the various electrochemical transduction mechanisms, and the choice of the recognition receptor molecules all influence the ultimate sensitivity of the sensor. New nanotechnology-based approaches, such as the use of engineered ion-channels in lipid bilayers, the encapsulation of enzymes into vesicles, polymersomes, or polyelectrolyte capsules provide additional possibilities for signal amplification. In particular, this review highlights the importance of the precise control over the delicate interplay between surface nano-architectures, surface functionalization and the chosen sensor transducer principle, as well as the usefulness of complementary characterization tools to interpret and to optimize the sensor response.

/pdf/electrochemical-biosensors-sensor-principles-and-5i1lr0kwi6.pdf

Electrochemical Biosensors - Sensor Principles and Architectures

Cellulose is the most abundant renewable carbon resource on earth and is an indispensable raw material for the wood, paper, and textile industries. A model system to study the mechanism of cellulose biogenesis is the bacterium Acetobacter xylinum which produces pure cellulose as an extracellular product. It was from this organism that in vitro preparations which possessed high levels of cellulose synthase activity were first obtained in both membranous and soluble forms. We recently demonstrated that this activity is subject to a complex multi-component regulatory system, in which the synthase is directly affected by an unusual cyclic nucleotide activator enzymatically formed from GTP, and indirectly by a Ca (2+) -sensitive phosphodiesterase which degrades the activator. The cellulose synthase activator (CSA) has now been identified as bis-(3' 5')-cyclic diguanylic acid (5'G3'p5'G3'p) on the basis of mass spectroscopic data, nuclear magnetic resonance analysis and comparison with chemically synthesized material. We also report here on intermediary steps in the synthesis and degradation of this novel circular dinucleotide, which have been integrated into a model for the regulation of cellulose synthesis.

Regulation of cellulose synthesis in Acetobacter xylinum by cyclic diguanylic acid.

Enzymes and Other Proteins Entrapped in Sol-Gel Materials

Biochemically active sol-gel glasses: The trapping of enzymes ☆

https://www.cell.com/trends/biotechnology/pdf/0167-7799(91)90020-I.pdf

Mycelial morphology and metabolite production

THE hormone- and neurotransmitter-dependent adenylate cyclases represent transmembrane regulatory systems in which the receptor unit faces the outside of the cell and the cyclase catalytic unit faces the inside. When the hormone or neurotransmitter binds to the receptor, the catalytic unit of the cyclase is activated and produces cyclic AMP at the inner surface of the membrane1. It has recently become clear that some hormone receptors are permanently coupled to adenylate cyclase whereas others are not. We demonstrate here that the effects of modulating membrane fluidity on the rate of adenlyate cyclase activation can be used to distinguish between the two modes of coupling.

Sergei Braun

Papers

Regulation of cellulose synthesis in Acetobacter xylinum by cyclic diguanylic acid.

Enzymes and Other Proteins Entrapped in Sol-Gel Materials

Biochemically active sol-gel glasses: The trapping of enzymes ☆

Mycelial morphology and metabolite production

Mode of coupling between hormone receptors and adenylate cyclase elucidated by modulation of membrane fluidity.