Study of human erythrocyte membrane proteins by 2-dimensional electrophoresis

Fractionation of human erythrocyte membrane proteins was performed using a modification of two-dimensional gel electrophoresis described by P. O'Farrel with isoelectric point plotted against molecular mass. All major erythrocyte proteins, including high molecular weight proteins, such as spectrin and band 3 protein, identified by one-dimensional sodium dodecyl sulfate gel electrophoresis, were visualized by silver staining of two-dimensional gels. All in all about 50 polypeptides were distinguished on two-dimensional electrophoretic patterns. Preliminary protein map was developed.     

Phenylalanine hydroxylase of human embryos: its homology with the enzyme from the liver of adults

Phenylalanine hydroxylase (PH) activity was discovered in the liver of 7-12 week old human embryos. Embryonic and adult PHs were identical, as shown by immunoelectrophoresis. Unlike the adult liver PH, the PH content of the extract of cytoplasmic proteins of embryonic liver was reduced but the specific activity was increased more than by one order of magnitude. H (57,000 D) and L (55,000 D) subunits were detected by immunoblotting. The L subunit predominates in the extract of membrane proteins of embryonic liver. Hence, the major part of phenylalanine oxidizing activity in the embryonic liver is related to the enzyme immunochemically identical with the PH of adult liver but differing from it in some structural and functional properties.     

The Physical Aspects of the Primary Interaction of Therapeutic Ultrasound with Biological Tissue

Biophysics - The biophysical aspects of the effects of ultrasound on biological tissues are considered. A mathematical model that describes the effects of the primary interaction of mechanical...     

A quantitative electron microscopic study of the respiratory parts of the lungs. II. The capillary network and septal spaces of the interalveolar septa]

A parallel histological and electron microscopic study of the capillary network of interalveolar septa has shown that in this microstructure there is only one two-dimensional capillary network, common for adjacent alveoles. In septal spaces of interalveolar septa the collagenic fibrils form an even thin network and additional collagenic bundles. The latter are mainly found in intercapillary septal spaces. The elastic fibres in interalveolar septa are found rarely, no interstitial cells being found at all.     

A new system for ATP-metric immunoanalysis

Treatment of amino-group-containing antigens with adenosine-5'-trimetaphosphate results in their chemical modification by -pppA residues. An immunoanalytical system is proposed based upon competition of these ATP-labelled antigens with those of the sample for immobilized antibodies. Mild acidic treatment of complexes of ATP-labelled antigens with immobilized antibodies results in quantitative liberation of intact ATP. The latter may be determined by the ultrosenstive bioluminescent techniques based upon emission of light with firefly luciferase. The validity of the system has been studied with two clinically important antigens, thyroxine and myoglobin.     

Evolution of ontogeny and nature of heterochronies

Every aspect of biological orderliness is a result of evolution, which expresses the systemic reorganization of organismal body plan, along with the way of its ontogenetic formation. Phyletic changes in the developmental rates (heterochronies) experienced by the organism or its structures exemplify just a kind of such consequences. The current belief that heterochronies are the causes of evolutionary events is based on the assumption that evolution of ontogeny proceeds in the same way as the ontogeny itself, i.e., from a germ cell to adult state. This premise (termed here “the central dogma”) is the cornerstone of traditional ideas of the evolutionary mechanism, regardless of whether it is perceived in terms of gene mutations or “embryonic modes.” In fact, the directions of two transformations compared are opposite each other. An evolutionary change in the body plan results from reorganization of the developmental system, which comes in response to disturbance of stability of the system’s terminal (adult) state. Realized by selection, this change starts immediately from the terminal state and then spreads in generations towards early ontogenetic stages. Heterochronies show just the same dynamics of events irrespective of whether they reflect the acceleration or delay of development. Empirically, such course of evolutionary changes was grounded most evidently by Severtsov in the early version of his concept of the phylembryogenesis. The theoretical basis of the same regularity is provided by the Schmalhausen–Waddington’s theory.     

A new protein of human atrium

The partial amino acid sequence (23 amino acid residues) of a protein isolated from human atrium has been determined. The sequence homology shows that this protein belongs to the myosin 1 light chain family (an atrium-specific isoform).     

Sensitized photomodification of DNA with binary systems of oligonucleotide conjugates. IV. Photoinduced electron transfer

The photomodification of single-stranded DNA sensitized to visible light (450-580 nm) by a binary system of oligonucleotide conjugates complementary to adjacent DNA sequences was studied. One oligonucleotide carries a residue of the photoreagent p-azidotetrafluorobenzaldehyde hydrazone at its 3'-terminal phosphate, and the other has a residue of the sensitizer, perylene or 1,2-benzanthracene, at the 5'-terminal phosphate. The rate of photomodification sensitized by the perylene derivative is 300,000-fold higher than the rate of photomodification in the absence of the sensitizer. Since the excitation energy of perylene is lower than the energy necessary for the initiation of azide photodecomposition, it is likely that the sensitization in the complementary complex occurs by electron transfer from the azido group of the photoreagent to the excited sensitizer. The sensitization by the 1,2-benzanthracene oligonucleotide derivative occurs by means of singlet-singlet energy transfer, which enables this sensitizer to act as a unconsumable catalyst each molecule of which is able to initiate the photomodification of more than 20 DNA molecules. By both mechanisms, the photomodification occurs with high specificity on the G11 residue of the target DNA. The degree of sensitized photomodification reaches 72%.     

Monomers for oligonucleotide synthesis with linkers carrying reactive residues: II. Synthesis of phosphoamidites based of uridine and cytosine and containing a linker with methoxyoxalamide groups in position 2'

A convenient preparative synthesis of 2'-amino-2'-deoxyuridine was developed. Starting from 2'-amino-2'-deoxyuridine and 2'-amino-2'-deoxycytidine, monomers for the phosphoamidite oligonucleotide synthesis were obtained that carry a linker with methoxyoxalamide groups in position 2'. The English version of the paper: Russian Journal of Bioorganic Chemistry, 2004, vol. 30, no. 3; see also http://www.maik.ru.