Phosphodiesterases 4B and 4D Differentially Regulate cAMP Signaling in Calcium Handling Microdomains of Mouse Hearts.

The ubiquitous second messenger 3',5'-cyclic adenosine monophosphate (cAMP) regulates cardiac excitation-contraction coupling (ECC) by signaling in discrete subcellular microdomains. Phosphodiesterase subfamilies 4B and 4D are critically involved in the regulation of cAMP signaling in mammalian cardiomyocytes. Alterations of PDE4 activity in human hearts has been shown to result in arrhythmias and heart failure.

cAMP Imaging at Ryanodine Receptors Reveals β-Adrenoceptor Driven Arrhythmias.

[Figure: see text].

Microbial Fermentation of Industrial Rice-Starch Byproduct as Valuable Source of Peptide Fractions with Health-Related Activity.

The rice-starch processing industry produces large amounts of a protein-rich byproducts during the conversion of broken rice to powder and crystal starch. Given the poor protein solubility, this material is currently discarded or used as animal feed. To fully exploit rice's nutritional properties and reduce this waste, a biotechnological approach was adopted, inducing fermentation with selected microorganisms capable of converting the substrate into peptide fractions with health-related bioactivity.

Angiotensin-II-Evoked Ca Entry in Murine Cardiac Fibroblasts Does Not Depend on TRPC Channels.

TRPC proteins form cation conducting channels regulated by different stimuli and are regulators of the cellular calcium homeostasis. TRPC are expressed in cardiac cells including cardiac fibroblasts (CFs) and have been implicated in the development of pathological cardiac remodeling including fibrosis. Using Ca imaging and several compound TRPC knockout mouse lines we analyzed the involvement of TRPC proteins for the angiotensin II (AngII)-induced changes in Ca homeostasis in CFs isolated from adult mice.

Using FRET-Based Fluorescent Sensors to Monitor Cytosolic and Membrane-Proximal Extracellular ATP Levels.

The assessment of local concentrations of extracellular ATP (eATP) at the site of receptor binding remains a challenge in the field of purinergic signaling. In many cases, biosensors exploiting the principle of Förster resonance energy transfer (FRET) have provided useful tools to visualize local concentrations of metabolites. A series of FRET-based biosensors based on the epsilon subunits of bacterial ATP synthases have been described for the visualisation of ATP.

Heart failure leads to altered β2-adrenoceptor/cyclic adenosine monophosphate dynamics in the sarcolemmal phospholemman/Na,K ATPase microdomain.

Aims: Cyclic adenosine monophosphate (cAMP) regulates cardiac excitation-contraction coupling by acting in microdomains associated with sarcolemmal ion channels. However, local real time cAMP dynamics in such microdomains has not been visualized before. We sought to directly monitor cAMP in a microdomain formed around sodium-potassium ATPase (NKA) in healthy and failing cardiomyocytes and to better understand alterations of cAMP compartmentation in heart failure.

FRET Microscopy for Real-Time Visualization of Second Messengers in Living Cells.

Förster Resonance Energy Transfer (FRET) microscopy is a useful tool in molecular biology and medical research to monitor and quantify real-time dynamics of protein-protein interactions and biochemical processes. Using this well-established technique, many novel signaling mechanisms can be investigated in intact cells or tissues and even in various subcellular compartments. Here, we describe how to perform FRET measurements in living cells expressing FRET-based biosensors and how to evaluate these data.

Peptide Fractions Obtained from Rice By-Products by Means of an Environment-Friendly Process Show In Vitro Health-Related Bioactivities.

Recently, the isolation of new health-related bioactive molecules derived from agro-food industrial by-products by means of environment-friendly extraction processes has become of particular interest. In the present study, a protein by-product from the rice starch industry was hydrolysed with five commercial proteolytic enzymes, avoiding the use of solvents or chemicals. The digestion processes were optimised, and the digestates were separated in fractions with four different molecular weight ranges by using a cross-flow membrane filtration technique.

Extracellular aromatic biosurfactant produced by Tsukamurella pseudospumae and T. spumae during growth on n-hexadecane.

Biosurfactants are surface-active agents produced by microorganisms and show increasing significance in various industrial applications. A great variety of these secondary metabolites are described to occur within actinomycetes, amongst trehalose lipids and oligosaccharide lipids produced by the family Tsukamurellaceae. This study reports on the production of not yet described compounds with surface active behavior by non-pathogenic Tsukamurella pseudospumae and Tsukamurella spumae during growth on hydrophobic carbon sources.

Advances in inline quantification of co-eluting proteins in chromatography: Process-data-based model calibration and application towards real-life separation issues.

Pooling decisions in preparative liquid chromatography for protein purification are usually based on univariate UV absorption measurements that are not able to differentiate between product and co-eluting contaminants. This can result in inconsistent pool purities or yields, if there is a batch-to-batch variability of the feedstock. To overcome this analytical bottleneck, a tool for selective inline quantification of co-eluting model proteins using mid-UV absorption spectra and Partial Least Squares Regression (PLS) was presented in a previous study and applied for real-time pooling decisions.

Trehalose lipid biosurfactants produced by the actinomycetes Tsukamurella spumae and T. pseudospumae.

Actinomycetales are known to produce various secondary metabolites including products with surface-active and emulsifying properties known as biosurfactants. In this study, the nonpathogenic actinomycetes Tsukamurella spumae and Tsukamurella pseudospumae are described as producers of extracellular trehalose lipid biosurfactants when grown on sunflower oil or its main component glyceryltrioleate. Crude extracts of the trehalose lipids were purified using silica gel chromatography.