Effect of DEAE-dextran upon the interaction of polynucleotides in poly (l+c) double complex]

It has been shown that the formation of poly(I+C) double complex is accompanied by appearance of the 244 nm CD band which is absent from the spectrum of the initial components. The amplitude of this CD band is maximum upon equimolar ratio of components. When one mixes the complementary polynucleotides bound to DEAE-dextran (D-d) double comples is not formed. CD spectrum of poly (I+C) double complex is changed considerably upon addition of D-d: CD increases when P/N ratio is 10:1, decreases at P/N 1:1 and comes back to the initial spectrum at P/N 1:5. Thermal dissociation of poly(I+C) when the anionic component was in surplus was similar to poly(I+C) alone (Tm equals 67 degrees) when the polydextran was in excess; the thermal dissociation was lower (Tm equals 43 degrees) than that of poly (I+C). It is discussed the possible mechanism of the D-d and poly (I+C) interaction.     

Antibacterial treatment of infectious-toxic shock

The studies enabled one to identify six leading clinicophysiological syndromes developing in patients with infective toxic shock (ITS). They include signs of purulent inflammatory processes, organ disorders and systems disturbances. Despite the clinical picture polymorphism, ITS has a clearly defined stage-by-stage process which makes it possible to determine hyperdynamic and hypodynamic phases of the pathological process within each stage. An absolute condition for antimicrobial drugs includes the following: drainage of the purulent inflammatory focus, arresting of pathogen discharge into the blood flow, recovery of host impaired functions and their maintenance. It was shown that a wrong choice of the drugs and antibacterial therapy regimens resulted in a 2-fold increase in fatal cases with ITS. Disorders in systemic and organ blood flows and microcirculation and coagulation disturbances played a particular role in decreasing antibacterial therapy efficacy. Further ways for optimizing antibacterial therapy are mainly connected with availability of efficient antibacterial drugs for practitioners and introduction of microbiological and pharmacokinetic monitoring of antibacterial therapy providing conditions for their rational and safe use.     

Specificity of Isatin Interaction with Cytochromes P450

Cytochrome P450-dependent monooxygenase systems exist basically in all living organisms, where they perform various important functions. The coordinated functioning of these systems involves many proteins participating in different protein-protein interactions (PPI). Previously, we have found that the endogenous non-peptide bioregulator isatin (indoledione-2,3), synthesized from indole by means of certain cytochromes P450 (e.g. P450 2E1, P450 2C19, P450 2A6) regulates affinity of some PPI. In this study, an attempt has been undertaken to register a direct interaction of isatin with a set of different proteins related to the functioning of cytochrome P450-dependent monooxygenase systems: five isoforms of cytochromes P450, two isoforms of cytochrome b₅, cytochrome P450 reductase, adrenodoxin, adrenodoxin reductase and ferrochelatase. The study has shown high affinity specific binding of isatin only to cytochromes P450 (the equilibrium dissociation constant (K_d) is about 10^–8 M).     

A Positive Feedback between Growth and Polarity Provides Directional Persistency and Flexibility to the Process of Tip Growth

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Whole-genome sequencing of eukaryotes: From sequencing of DNA fragments to a genome assembly

Rapid advances in sequencing technologies of second- and even third-generation made the whole genome sequencing a routine procedure. However, the methods for assembling of the obtained sequences and its results require special consideration. Modern assemblers are based on heuristic algorithms, which lead to fragmented genome assembly composed of scaffolds and contigs of different lengths, the order of which along the chromosome and belonging to a particular chromosome often remain unknown. In this regard, the resulting genome sequence can only be considered as a draft assembly. The principal improvement in the quality and reliability of a draft assembly can be achieved by targeted sequencing of the genome elements of different size, e.g., chromosomes, chromosomal regions, and DNA fragments cloned in different vectors, as well as using reference genome, optical mapping, and Hi-C technology. This approach, in addition to simplifying the assembly of the genome draft, will more accurately identify numerical and structural chromosomal variations and abnormalities of the genomes of the studied species. In this review, we discuss the key technologies for the genome sequencing and the de novo assembly, as well as different approaches to improve the quality of existing drafts of genome sequences.     

Isatin‐induced increase in the affinity of human ferrochelatase and adrenodoxin reductase interaction

Isatin (indol‐2,3‐dione) is an endogenous non‐peptide regulator exhibiting a wide range of biological and pharmacological activities, which are poorly characterized in terms of their molecular mechanisms. Identification of many isatin‐binding proteins in the mammalian brain and liver suggests that isatin may influence their functions. We have hypothesized that besides direct action on particular protein targets, isatin can act as a regulator of protein–protein interactions (PPIs). In this surface plasmon resonance‐based biosensor study we have found that physiologically relevant concentrations of isatin (25‐100 μM) increase affinity of interactions between human recombinant ferrochelatase (FECH) and NADPH‐dependent adrenodoxin reductase (ADR). In the presence of increasing concentrations of isatin the Kd values demonstrated a significant (up to 6‐fold) decrease. It is especially important that the interaction of isatin with each individual protein (FECH, ADR) was basically negligible and therefore could not contribute to the observed effect. This effect was specific only for the FECH/ADR complex formation and was not observed for other protein complexes studied: FECH/cytochrome b5(CYB5A) and FECH/SMAD4.     

PASylation technology improves recombinant interferon-β1b solubility,stability, and biological activity

Applied Microbiology and Biotechnology - Recombinant interferon-β1b (IFN-β1b) is an effective remedy against multiple sclerosis and other diseases. However, use of small polypeptide...