Asymmetry of movement direction as a tactic in the feeding behavior of rats

The sign and degree of spatial-motor asymmetry in rats were studied in conditions both of spontaneous or signalled choice in an U-maze and spontaneous multiple choice in a radial labyrinth. It was shown that during investigation of a new environment, motor asymmetry in rats was feebly expressed in all conditions of experiments, irrespective of the labyrinth scheme and experimental procedures. In the process of training, adequate behaviour was formed and in some conditions a distinctly expressed spatial asymmetry appeared, while in other cases it was absent. Apparently, while investigating an "unknown" situation (where rats can move rightwards and leftwards), the strategy of "displacement" is characteristic of them. Later the rate of asymmetry manifestation depends on concrete spatial and temporal characteristics of already "familiar" surroundings.     

Preparation and properties of trypsin from the pyloric caeca of Pacific Ocean salmon

Trypsin from pyloric caeca of Pacific salmon was purified by affinity chromatography of the water extract on hexamethylenediamine-glycidylmethacrylate-cellulose. A protein band with a molecular weight of 22.5 kDa was found on SDS-electrophoresis in PAG. The protein band was homogeneous according to isoelectrofocusing in PAG (pI 4.0). The amino acid composition of the enzyme is typical of trypsin anionic forms; the major difference from the cationic forms is the lower content of lysine. The differences in properties caused by change of the enzyme molecule charge are similar to those observed in cationic trypsin when the lysine epsilon-amino groups of the latter are modified (change of pI, shift of the pH-optimum towards basic values, increase of stability to autolysis). Some natural trypsin inhibitors of the different origin suppressed the enzyme activity of trypsin from Pacific salmon in typical stoichiometric ratios. An unusual interaction of the enzyme with the specific inhibitor N-L-tosyl-L-lysine chloromethyl ketone was observed.     

The amino acid sequences of two alpha chains of hemoglobins from Komodo dragon Varanus komodoensis and phylogenetic relationships of amniotes

To elucidate phylogenetic relationships among amniotes and the evolution of alpha globins, hemoglobins were analyzed from the Komodo dragon (Komodo monitor lizard) Varanus komodoensis, the world's largest extant lizard, inhabiting Komodo Islands, Indonesia. Four unique globin chains (alpha A, alpha D, beta B, and beta C) were isolated in an equal molar ratio by high performance liquid chromatography from the hemolysate. The amino acid sequences of two alpha chains were determined. The alpha D chain has a glutamine at E7 as does an alpha chain of a snake, Liophis miliaris, but the alpha A chain has a histidine at E7 like the majority of hemoglobins. Phylogenetic analyses of 19 globins including two alpha chains of Komodo dragon and ones from representative amniotes showed the following results: (1) The a chains of squamates (snakes and lizards), which have a glutamine at E7, are clustered with the embryonic alpha globin family, which typically includes the alpha D chain from birds; (2) birds form a sister group with other reptiles but not with mammals; (3) the genes for embryonic and adult types of alpha globins were possibly produced by duplication of the ancestral alpha gene before ancestral amniotes diverged, indicating that each of the present amniotes might carry descendants of the two types of alpha globin genes; (4) squamates first split off from the ancestor of other reptiles and birds.      

Effect of Soviet bleomycin-bleomycetin on the body of animals in multiple parenteral administration]

Toxicity of bleomycetin was studied on 3 animal species (rats, rabbits and dogs). The antibiotic was administered intramuscularly and intravenously in various doses for a prolonged period of time. The death of the rats, rabbits and dogs treated with repeated lethal doses of bleomycetin was due to its toxic effect on the kidneys and probably lungs. The level of urea in the blood of the animals before death increased up to 300--400 mg %. Histological examination of the kidneys revealed the picture of glomerulonephritis. The lungs were highly plethoric and showed areas of alveolar collapse and consolidation consisting mainly of the collapsed alveolar epithelium. The liver was not affected by bleomycetin according to both the results of some functional tests and histological examination. tthe blood sugar level after bleomycetin administration was not altered significantly. The changes in the peripheral blood were not pronounced. An increased P wave, decreased R wave and deep S wave were seen on the ECG. Such deviitions may be due not only to the changes in the myocardium but also to the lung affection. When bleomycetiin was used repeatedly in nonlethal doses (1 mg/kg for rats, 1--2 mg/kg for rabbits and 0.25--0.5 mg/kg for dogs), the above changes were less pronounced or not manifested at all. No inhibitory effect on hemopoiesis is an important positive characteristics of bleomycetin, so that it compares very favourably with most other antitumor drugs.     

Information contents and dinucleotide compositions of plant intron sequences vary with evolutionary origin

The DNA sequence composition of 526 dicot and 345 monocot intron sequences have been characterized using computational methods. Splice site information content and bulk intron and exon dinucleotide composition were determined. Positions 4 and 5 of 5 splice sites contain different statistically significant levels of information in the two groups. Basal levels of information in introns are higher in dicots than in monocots. Two dinucleotide groups, WW (AA, AU, UA, UU) and SS (CC, CG, GC, GG) have significantly different frequencies in exons and introns of the two plant groups. These results suggest that the mechanisms of splice-site recognition and binding may differ between dicot and monocot plants.     

Preparation of androsta-1,4-diene-3,17-dione from sterols using Mycobacterium neoaurum VKPM As-1656 strain

A product of microbiological cleavage of the sterols side chain, androsta-1,4-diene-3,17-dione, is toxic for bacteria, in particular, actinobacteria of the genera Mycobacterium and Arthrobacter. Sterols were transformed into androsta-1,4-diene-3,17-dione by culturing the M. neoaurum VKPM An-1656 strain in a high yield, provided that a sorbent was used for elimination of contact between the bacterial cells and the product. Unlike the cholesterol side chain, the more branched chains of phytosterols were cleaved in the presence of M. neoaurum at a high rate only under turbulent stirring of the culture medium, which intensified the formation of hydrocarbonate ion from NaNI3 in situ.     

Protein splicing

Inteins are internal polypeptide sequences that are posttranslationally excised from a protein precursor by a self-catalyzed protein-splicing reaction. Most of inteins consist of N- and C-terminal protein splicing domain and central endonuclease domain. The endonuclease domain can initiate mobility of the intein gene, this process being named intein homing. This review is focused on the recent data about the structure and function of inteins. Main intein-mediated protein-engineering applications, such as protein purification, ligation and cyclization, new forms of biosensors, are presented.     

Abnormal methylation of p16/CDKN2A AND p14/ARF genes GpG Islands in non-small cell lung cancer and in acute lymphoblastic leukemia

Multiplex methylation-sensitive PCR and methylation-specific PCR were employed in studying the methylation of CpG islands in the p16/CDKN2A and p14/ARF promoter and the first exon regions in non-small cell lung cancer (54 samples) and acute B-cell lymphoblastic leukemia (61 samples). Differences in methylation were detected between types of neoplasia as well as between CpG islands studied within the same types of tumors. High level of the p16/CDKN2A first exon CpC island methylation was revealed in non-small cell lung cancer (68%) and in acute B-cell lymphoblastic leukemia (55%) and the CpG island of p14/ARF first exon was nonmethylated in these types of tumors. The methylation of CpG-rich fragments of genes p16/CDKN2A and p14/ARF promoters was analysed. As was found out, CpG islands located in 5' areas of one and the same gene can differ in methylation frequencies. The comparison of sensitivity between methylation-specific PCR and methylation-sensitive PCR used in the methylations studies was carried out.     

Identification of genetically modified vegetable sources in food and feed using hydrogel oligonucleotide microchip

A method of multiplex polymerase chain reaction (PCR) followed by the hybridization on a hydrogel oligonucleotide biochip was developed for simultaneous identification of ten different transgenic elements of plant DNA in feed and food products. The biochip contained 22 immobilized probes intended for (i) detection of plant DNA; (ii) plant species determination (soybean, maize, potato, rice); (iii) identification of transgenic elements, including 35S CaMV, 35S FMV, rice actine gene promoters, nos, 35S CaMV, ocs, pea rbcS1 gene terminators, and bar, gus, nptII marker genes. The limit of detection was 0.5% of genetically modified (GM) soybean and maize in analyzed samples. Identification of transgenic DNA in food and feed products using either the developed approach or real-time PCR led to virtually identical results. The assay can be used for selection of GM samples by screening food and feed products for subsequent quantitative determination of the GM component based on the identified transgene.