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Molecularly-imprinted polymers (MIPs) involving vinylpyrrolidone, methacrylic acid, hydroxyethylmethacrylate and cross-linker - ethyleneglycol dimethacrylate have been synthesized and comparative evaluation of their sorption characteristics towards pollutants - 4-nitrophenol and phenol has been provided. [ABSTRACT FROM AUTHOR]

As a result of sequencing the genome of the termophilic alkali-tolerant lipolytic bacterium Thermosyntropha lipolytica, the gene encoding a lipase secreted into the medium was identified. The recombinant enzyme was expressed in Escherichia coli. It was isolated, purified, and functionally characterized. The lipase exhibited hydrolytic activity toward para-nitrophenyl esters of various chain lengths, as well as triglycerides, including vegetable oils. The optimal reaction conditions were achieved at temperatures from 70 to 80 degrees C and pH 8.0. Enzyme saved more than 80% of its activity in the presence of 10% methanol. This new thermostable lipase may be a promising biocatalyst for organic synthesis; it may find application in the food and detergent industry and biodiesel production.

Dopamine receptors agonists and catechol-O-methyltransferase (COMT) inhibitors are the novel classes of the drugs for Parkinson's disease (PD) treatment in both early and late stages. In the latter one, there is an increase of substantia nigra neurons degeneration, striatum denervation, changes of dopamine receptors state, dysregulation of Levadopa uptake, dopamine synthesis and storage, decrease of dopamine receptors density in striatum that results in clinical picture alteration and development of pharmaco-therapeutic side-effects, as well as motor fluctuations and drug diskinesias. The use of dopamine receptors agonists and COMT inhibitors at the late PD stages in combination with other antiparkinsonian medications allows improving pharmaco-therapeutic efficacy, along with patient's daily activity and quality of life.

Inhibition of catechol-0-methyltransferase (COMT) activity by Tolcapone was shown to result in increase of the striatal DA extracellular content in unrestrained rats pretreated with L-3,4-dihydroxyphenilalanine combined with Carbidopa, the decarboxylation inhibiting agent. Tolcapone enhanced the increase of the DA level in the rat striatal dialysates produced by treatment of these animals with specific DA re-uptake blocker GBR 12909. The latter elicits stereotype behaviour in rats that is substantially enhanced by tolcapone. The DA turnover rate in the striatum was decreased by the GBR 12909. The data obtained suggest that the DA transporter of neuronal membrane plays a major role in the neurochemical homeostasis at synaptic level.

In vivo brain functions analysis was conducted to assess the effect of tolcapone, a novel catechol-O-methyltransferase (COMT) inhibitor on extracellular levels of dopamine (DA) and its metabolites dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA) in the striatum of awake, freely moving eats during GBR 12909-induced blockade of DA uptake. Tolcapone administration (30 mg/kg, i.p.) failed to change the dopamine output but caused a marked and long-lasting decrease in the extracellular level of HVA and increase in that of DOPAC. In contrast, injection of the DA uptake inhibitor GBR 12909 directly into the striatum (5 microM) or i.p. (20 mg/kg) led to increase in the DA level but had no significant effect on the metabolites. Co-administration of tolcapone (30 mg/kg i.p.) and CBR 12909 (20 mg/kg) increased the DA level further, whereas the changes in HVA and DOPAC levels remained approximately the same as after injection of tolcapone alone. Behavioral observation showed GBR 12909-induced hyperactivity and stereotypy to be potentiated by tolcapone. These findings show that in the rat striatum under conditions of normal nerve activity DA uptake completely inhibits the increase in striatal DA neurotransmission induced by tolcapone (30 mg/kg i.p.) through COMT inhibition.

A comparative evaluation of the developed variants of indirect solid-phase enzyme immunoassay using fluorogenic and chromogenic substrates for the determination of Marburg virus antigen was carried out. The resolving capacity of this method was 3.8 x 10(-9) g of protein for the former and 3.1 x 10(-8) g of protein for the latter substrate. Cross titrations demonstrated the lack of common antigens with Ebola virus.

The structural accessibility of tryptophan residues in leucyl-tRNA synthetase from cow mammary gland has been studied using chemical modifications by N-bromosuccinimide and 2-hydroxy-5-nitrobenzyl bromide. The modifications were monitored by UV absorbance and intrinsic fluorescence of the enzyme's tryptophan residues. Under native conditions, at pH 7,8, only two exposed tryptophan residues are modified in each subunit of the dimeric enzyme. Under denaturing conditions, in 6 M guanidine hydrochloride solution, internal tryptophan residues are also modified as a consequence of unfolding of the native tertiary structure of the enzyme. Modifications of tryptophan residues resulted in inactivation of leucyl-tRNA synthetase both in aminoacylation and ATP-PPi exchange reactions. In the specific complex of leucyl-tRNA synthetase with the cognate tRNALeu one of exposed tryptophan residues is protected by tRNALeu and is not modified by the above reagents.

Studies have been made on thermal synthesis of peptides containing amino acids (glycine, alanine, leucine, threonine, and histidine) and succinic acid. The synthetic products were found to be heterogeneous, comprising mostly linear polymers. In the peptides obtained, the ratio between individual amino acids differed from the initial one. It was demonstrated that glycine exhibits high capacity for polymerization. At the same time, most polymerized peptides contained large amounts of leucine. In hydrolyzates of some of the peptides, a new non-identified amino acid was found which was formed from threonine. The peptides obtained exhibited catalytic properties: they hydrolyzed-p-nitrophenyl-phosphate, increased the breakdown of ascorbic acid by hydrogen peroxide and splitted inorganic phosphate from ATP. These activities depended on PH of the medium, the duration of action and substrate concentration. Synthetic products which contained threonine residues, exhibited higher activities as compared to other peptides. The data obtained reveal a possibility of incorporating the organic acids into polypeptide chains during abiogenic synthesis of biologically active substances. Such compounds with non-specific catalytic properties could serve as one of the steps in evolution of biocatalyzers.