生物化学技术

Enzyme stabilization is important for any biomedical or industrial application of enzymes. In many applications, the goal is to provide extended active lifetime at normal environmental conditions with traditional substrates at low concentrations in buffered solutions. Howe ...

Phospholipid vesicle (liposome) offers an aqueous compartment surrounded by lipid bilayer membranes. Various enzyme molecules were reported to be encapsulated in liposomes. The liposomal enzyme shows peculiar catalytic activity and selectivity to the substrate in the bulk li ...

Widespread interest in the use of room temperature ionic liquids (RTILs) as solvents in anhydrous biocatalytic reactions has largely been met with underwhelming results. Enzymes are frequently inactivated in RTILs as a result of the influence of solvent on the enzyme’s microenvironm ...

Recent pursuit on utilization of nanoscale materials has manifested a variety of configurations of highly efficient enzymic biocatalyst systems for biotechnological applications. Nanoscale structures are particularly powerful in effecting multienzyme biocataly ...

This chapter describes methods for enzyme stabilization using micellar solutions. Micellar solutions have been shown to increase the thermal stability, as well as the pH and solvent tolerance of enzymes. This field is traditionally referred to as micellar enzymology. This paper detai ...

While biocatalysts show tremendous potential for the industrial production of fine chemicals, their integration into large-scale processes has been slow. One of the main reasons for slow acceptance in industry is the inherent instability of the enzymes. Recent developments in bioen ...

Effective entrapment of enzymes in solid-phase materials is critical to their practical application. The entrapment generally stabilizes biological activity compared to soluble molecules and the material simplifies catalyst integration significantly. A silica sol-gel ...

Nanoporous gold (NPG) is a material of emerging interest for immobilization of biomolecules and �especially enzymes. NPG materials provide a high gold surface area onto which biomolecules can either be directly physisorbed or covalently linked after first modifying the NPG with a self ...

A selection of the best combination of adequate immobilization support and efficient immobilization method is still a key requirement for successful application of immobilized enzymes on the industrial level. Eupergit� supports exhibit good mechanical and chemical properti ...

Ca2+-ATP pumps (those on the plasma membrane; PMCA and sarcoplasmic reticulum; SERCA1) have an important role to play in the regulation of intracellular calcium concentrations. In this chapter, three preparations, two membranes and a purified enzyme, best suited for studies of Ca2+-ATPa ...

A range of techniques have been used to measure the concentration of cytosolic-free Ca2+ (cyt) in plant cells. Fluorescent Ca2+-sensitive indicators have been used extensively to measure plant cyt and a number of techniques are available for loading these into plant cells. Here we describe a me ...

Within single cells there is a complex myriad of signaling which controls physiological process many of which are modulated, or signaled directly, by intracellular calcium ions. Understanding the exquisitely sensitive, and spatially restricted, changes in calcium has been of inte ...

High throughput calcium mobilization assays are extensively used for pharmacological characterization of GPCR ligands. These approaches, initially developed for Gq-coupled receptors, can be extended to Gi coupled GPCRs using chimeric G proteins. Here we used the Gαqi5 protein to ...

In the last two decades the study of Ca2+ homeostasis in living cells has been enhanced by the explosive development of genetically encoded Ca2+-indicators. The cloning of the Ca2+-sensitive photoprotein aequorin and of the green fluorescent protein (GFP) from the jellyfish Aequorea vic ...

Although changes in both pHin and i have been observed in response to a variety of agonists, it is not clear whether these ionic events work independently or are coordinated to lead to a specific physiological response. One of the fundamental problems in studying these ionic events is that changes in p ...

Increases in bulk average cytoplasmic Ca2+ concentration (c) are derived from the combined activities of many Ca2+ channels. Near (

The use of single- and dual-wavelength Ca2+-sensitive fluorescent dyes to monitor changes in endothelial and/or smooth muscle intracellular Ca2+ levels has provided information linking Ca2+ events to changes in arterial function. Here we describe the in vitro techniques used to selec ...

Changes in the cytosolic Ca2+ concentrations (i) play a primary role in the regulation of the contraction of smooth muscle cells. However, the relationship between i and tension exhibits a temporal change during the time course of contraction or relaxation. The extent of the tension developm ...

Calcium recording from whole heart is an important technique to investigate role of calcium in cardiac arrhythmias. Intracellular calcium can be recorded from multiple locations using imaging devices and organic dyes or genetic probe (Tallini et al. PNAS 103(12):4753–4758, 2006) from w ...

Data on the production of inositol phosphates is a useful complement to measurements of intracellular Ca2+. The basic principle is labeling of the inositol lipids by growing the appropriate cell line in culture in the presence of inositol for 2–3 days to reach labeling equilibrium. Lithium ions ...