Speed characterization of p-i-n photodiode based on GaSb/GaInAsSb/GaAlAsSb heterostructure with frontal bridge contact at 1.9 µm.

We report a study of the response function parameters (amplitude and rise/fall time) of a high-speed GaSb/GaInAsSb/GaAlAsSb photodiode operating at 1.9 µm as a function of optical input power and reverse bias voltage. The experimental measurement results yield the optimal pulse energy and optimal reverse bias voltage for the photodiode.

PPARGC1A gene polymorphism is associated with exercise-induced fat loss.

Obesity is a widespread problem within modern society, serving to increase the risk of cardiovascular, metabolic, and neurodegenerative disorders. Peroxisome proliferator-activated receptor gamma (PPARγ) and PPARγ coactivator 1 α (PGC1α) play a key role in the regulation of cellular energy metabolism and is implicated in the pathology of these diseases. This study examined the association between polymorphisms of the PPARG and PPARGC1A genes and individual variability in weight loss in response to physical activity intervention.

A novel peptide dendrimer LTP efficiently facilitates transfection of mammalian cells.

One of the urgent problems of gene therapy is the search for effective transfection methods. Synthetic cationic peptides (CPs) are considered to be one of the most promising approaches for intracellular transport of oligonucleotides. Almost unlimited possibilities of the architectural design of CPs (linear and cyclic structures with a variation of chirality as well as dendrimers) make CPs an effective tunable carrier in this field.

Emerging evidence for potential role of Ca-ATPase-mediated calcium accumulation in symbiosomes of infected root nodule cells.

Symbiosomes are organelle-like compartments responsible for nitrogen fixation in infected nodule cells of legumes, which are formed as a result of symbiotic association of soil bacteria rhizobia with certain plant root cells. They are virtually the only source of reduced nitrogen in the Earth's biosphere, and consequently, are of great importance. It has been proven that the functioning of symbiosomes depends to a large extent on the transport of various metabolites and ions - most likely including Ca2+ - across the symbiosome membrane (SM).

Comparative molecular cytogenetic characterization of seven Deschampsia (Poaceae) species.

The genus Deschampsia P. Beauv (Poaceae) involves a group of widespread polymorphic species. Some of them are highly tolerant to stressful and variable environmental conditions, and D.

Molecular Cytogenetic Analysis of Deschampsia antarctica Desv. (Poaceae), Maritime Antarctic.

Deschampsia antarctica Desv. (Poaceae) (2n = 26) is one of the two vascular plants adapted to the harshest environment of the Antarctic. Although the species is a valuable model for study of environmental stress tolerance in plants, its karyotype is still poorly investigated.

Histidine-mediated xylem loading of zinc is a species-wide character in Noccaea caerulescens.

Histidine plays a crucial role in nickel (Ni) translocation in Ni-hyperaccumulating plants. Here, we investigated its role in zinc (Zn) translocation in four accessions of the Zn hyperaccumulator, Noccaea caerulescens, using the related non-hyperaccumulator, Thlaspi arvense, as a reference. We compared the effects of exogenous histidine supply on Zn xylem loading, and of Zn-histidine complex formation on Zn uptake in energized tonoplast vesicles.

Quantum-dot-based immunochromatographic assay for total IgE in human serum.

To rapidly quantify total immunoglobulin E levels in human serum, we developed a novel quantum-dot-based immunochromatographic assay that employs digital recording of fluorescence. It can detect IgE levels of 5-1000 kU/L, with a coefficient of variation ranging from 2.0 to 9.

Towards a novel influenza vaccine: engineering of hemagglutinin on a platform of adenovirus dodecahedron.

Background: The production process for the current influenza vaccine takes about 6 months and its antigenic composition must be modified annually. In the attempt towards developing influenza vaccine production that would be faster, safer and cheaper we engineered an influenza vaccine in which multiple copies of hemagglutinin (HA) would be delivered by a vector, adenovirus dodecahedron (Ad Dd). Dd is a virus-like particle, formed by assembly of twelve copies of pentameric penton base (Pb) proteins responsible for virus penetration.

Biochemical characteristics of the Ca2+ pumping ATPase in the peribacteroid membrane from broad bean root nodules.

Ca(2+)-ATPase in the peribacteroid membrane (PBM) of symbiosomes isolated from Vicia faba root nodules was characterized in terms of its hydrolytic and transport activities. Both activities were found to be pH-dependent and exhibit pH optimum at pH 7.0.

Cylindrical inclusion protein of potato virus A is associated with a subpopulation of particles isolated from infected plants.

Potato virus A (PVA) particles were purified by centrifugation through a 30 % sucrose cushion and the pellet (P1) was resuspended and sedimented through a 5-40 % sucrose gradient. The gradient separation resulted in two different virus particle populations: a virus fraction (F) that formed a band in the gradient and one that formed a pellet (P2) at the bottom of the gradient. All three preparations contained infectious particles that retained their integrity when visualized by electron microscopy (EM).

Evidence for direct amelogenin-target cell interactions using dynamic force spectroscopy.

Increasing evidence suggests that amelogenin, long held to be a structural protein of developing enamel matrix, may also have cell signaling functions. However, a mechanism for amelogenin cell signaling has yet to be described. The aim of the present study was to use dynamic chemical force spectroscopy to measure amelogenin interactions with possible target cells.

An unusual structure at one end of potato potyvirus particles.

The particles of potato virus Y (PVY) and potato virus A (PVA) potyviruses are helically constructed filaments that are thought to contain a single type of coat protein subunit. Examination of negatively stained virions by electron microscopy reveals flexuous rod-shaped particles with no obvious terminal structures. It is known that some helically constructed rod-shaped virus particles incorporate additional minor protein components, which form stable complexes that mediate particle disassembly, movement or transmission by vectors.

Functional identification of electrogenic Na+-translocating ATPase in the plasma membrane of the halotolerant microalga Dunaliella maritima.

The hypothesis that the primary Na+-pump, Na+-ATPase, functions in the plasma membrane (PM) of halotolerant microalga Dunaliella maritima was tested using membrane preparations from this organism enriched with the PM vesicles. The pH profile of ATP hydrolysis catalyzed by the PM fractions exhibited a broad optimum between pH 6 and 9. Hydrolysis in the alkaline range was specifically stimulated by Na+ ions.

Molecular interactions between a plant virus movement protein and RNA: force spectroscopy investigation.

RNA-protein interactions are fundamental for different aspects of molecular biology such as gene expression, assembly of biomolecular complexes or macromolecular transport. The 3a movement protein (MP) of a plant virus, Cucumber mosaic virus (CMV), forms ribonucleoprotein (RNP) complexes with viral RNA, capable of trafficking from cell-to-cell throughout the infected plant only in the presence of the CMV capsid protein (CP). However, deletion of the C-terminal 33 amino acid residues of the CMV MP (in the mutant designated 3aDeltaC33 MP) resulted in CP-independent cell-to-cell movement.

Complex molecular architecture of beet yellows virus particles.

Closteroviruses possess exceptionally long filamentous virus particles that mediate protection and active transport of the genomic RNA within infected plants. These virions are composed of a long "body" and short "tail" whose principal components are the major and minor capsid proteins, respectively. Here we use biochemical, genetic, and ultrastructural analyses to dissect the molecular composition and architecture of particles of beet yellows virus, a closterovirus.

The Na+-translocating ATPase in the plasma membrane of the marine microalga Tetraselmis viridis catalyzes Na+/H+ exchange.

Our previous investigations have established that Na+ translocation across the Tetraselmis viridis plasma membrane (PM) mediated by the primary ATP-driven Na+-pump, Na+-ATPase, is accompanied by H+ counter-transport [Y.V. Balnokin et al.

The C-terminal 33 amino acids of the cucumber mosaic virus 3a protein affect virus movement, RNA binding and inhibition of infection and translation.

The capsid protein (CP) of Cucumber mosaic virus (CMV) is required for cell-to-cell movement, mediated by the 3a movement protein (MP). Deletion of the C-terminal 33 amino acids of the CMV 3a MP (in the mutant designated 3aDeltaC33 MP) resulted in CP-independent cell-to-cell movement, but not long-distance movement. RNA-binding studies done in vitro using isolated bacterially expressed MP showed that the 3aDeltaC33 MP bound RNA more strongly, with fewer regions sensitive to RNase and formed cooperatively bound complexes at lower ratios of protein : RNA than the wild-type (wt) 3a MP.

Calcium release from Synechocystis cells induced by depolarization of the plasma membrane: MscL as an outward Ca2+ channel.

Cells of the cyanobacterium Synechocystis sp. PCC 6803 are equipped with a mechanosensitive ion channel MscL that is located in their plasma membrane. However, the exact function of the channel in this freshwater cyanobacterium is unknown.

Umbravirus-encoded movement protein induces tubule formation on the surface of protoplasts and binds RNA incompletely and non-cooperatively.

Various functions of the cell-to-cell movement protein (MP) of Groundnut rosette virus (GRV) were analysed. The GRV ORF4-encoded protein was shown by immunofluorescence microscopy to generate tubular structures that protrude from the surface of the protoplast. The protein encoded by ORF4 was assessed also for RNA-binding properties.