Kinetic Studies on the Interaction of HIV-1 Gag Protein with the HIV-1 RNA Packaging Signal.

During HIV-1 virus assembly, the genomic RNA (vRNA) is selected for packaging by the viral protein Gag because it contains a specific packaging signal, Psi. While there have been numerous studies of Gag-Psi interactions, there is almost no information on the kinetic aspects of this interaction. We investigated the kinetics of Gag binding to different RNAs using switchSENSE DRX technology.

Peracetic acid-based disinfectant is the most appropriate solution for a biological decontamination procedure of responders and healthcare workers in the field environment.

Aims: An effective decontamination procedure of personnel wearing personal protective equipment is required by CBRN responders and healthcare workers when dealing with biological warfare agents or natural outbreaks caused by highly contagious pathogens. This study aimed to identify critical factors affecting the efficacy of peracetic acid (PAA)-based disinfectants and products containing either hydrogen peroxide or sodium hypochlorite under the same conditions.

Methods And Results: The influence of concentration, application (contact) time, erroneous human behaviour, interfering substance, technical assets and weather conditions on disinfection efficacy against Bacillus subtilis spores were assessed in 14 experimental groups.

Distinct Contributions of Different Domains within the HIV-1 Gag Polyprotein to Specific and Nonspecific Interactions with RNA.

Viral genomic RNA is packaged into virions with high specificity and selectivity. However, in vitro the Gag specificity towards viral RNA is obscured when measured in buffers containing physiological salt. Interestingly, when the binding is challenged by increased salt concentration, the addition of competing RNAs, or introducing mutations to Gag protein, the specificity towards viral RNA becomes detectable.

REFERENCE SURFACE FOR IN SITU GAMMA SPECTROMETRY.

Chemical laboratories of the Fire Rescue Service of the Czech Republic are part of the radiation monitoring network and participate in the radiation situation monitoring in the Czech Republic. Measurements in situ are crucial for monitoring the radiation situation in emergencies associated with the deposition of radioactive substances on a large area. Those data can be used for estimating a possible dose obtained either by staying in a contaminated area or by consumption of food produced in the area.

SELECTION OF SUITABLE SAMPLING TOOL FOR RELIABLE SOIL SAMPLING NOT ONLY AFTER RADIOLOGICAL ACCIDENT.

The objective of this research was to develop a sampling protocol for contaminated soils after a large radiological accident. One of the criteria for good sampling method is reproducibility and accuracy of large number of samples collected in short time. Members of the chemical laboratories of the Fire Rescue Service of the Czech Republic (FRS CR), which are included in Radiation Monitoring Network, tested four tools in different soil types.

Micromotors as "Motherships": A Concept for the Transport, Delivery, and Enzymatic Release of Molecular Cargo via Nanoparticles.

Nano/micromotors based on biodegradable and biocompatible polymers represent a progressively developing group of self-propelled artificial devices capable of delivering biologically active compounds to target sites. The majority of these machines are micron sized, and biologically active compounds are simply attached to their surface. Micron-sized devices cannot enter cells, but they provide rapid velocity, which scales down with the size of the device; nanosized devices can enter cells, but their velocity is negligible.

Efficient support of virus-like particle assembly by the HIV-1 packaging signal.

The principal structural component of a retrovirus particle is the Gag protein. Retroviral genomic RNAs contain a 'packaging signal' ('Ψ') and are packaged in virus particles with very high selectivity. However, if no genomic RNA is present, Gag assembles into particles containing cellular mRNA molecules.

Membrane Interactions of the Mason-Pfizer Monkey Virus Matrix Protein and Its Budding Deficient Mutants.

Matrix proteins (MAs) play a key role in the transport of retroviral proteins inside infected cells and in the interaction with cellular membranes. In most retroviruses, retroviral MAs are N-terminally myristoylated. This modification serves as a membrane targeting signal and also as an anchor for membrane interaction.

Cost-effective method for the preparation of uniformly labeled myristoylated proteins for NMR measurements.

Nuclear magnetic resonance (NMR) is a powerful technique for solving protein structures or studying their interactions. However, it requires molecules labeled with NMR sensitive isotopes like carbon (13)C and nitrogen (15)N. The recombinant expression of labeled proteins is simple to perform but requires quite expensive chemicals.

Interaction of Mason-Pfizer monkey virus matrix protein with plasma membrane.

Budding is the final step of the late phase of retroviral life cycle. It begins with the interaction of Gag precursor with plasma membrane (PM) through its N-terminal domain, the matrix protein (MA). However, single genera of Retroviridae family differ in the way how they interact with PM.