Restriction map of permuted DNA of Erwinia carotovora temperate bacteriophage 59

The cyclic permutation and terminal redundancy were found in the genomes of Erwinia carotovora temperate bacteriophage 59 by electron microscopic studies. The headful mechanism for bacteriophage DNA cleavage and packaging during the phage morphogenesis was confirmed by the restriction analysis technique. Restriction map of the bacteriophage 59 DNA was constructed for restriction endonucleases BamHI, Bg1II, Eco31, Sa1I, SmaI, EcoRI.     

Binding of SSB-protein from Ehrlich ascites carcinoma cells with DNA and polyribonucleotides]

Binding of SSB-protein from Ehrlich ascites tumor to ssDNA from M13 phage leads to its compactization. The structure of the complex at the protein/DNA ratios far from the saturation level looks like "beads-on the string". DNA that was fully saturated with protein forms collapsed globular structure. Binding of the protein to the dsDNA from phage lambda increases its flexibility and decreases the coil dimensions; no "beads-on the string" structure are seen. The protein possess slight destabilizing effect on hairpin helices of M13DNA. Competition studies demonstrate that the binding properties of protein with polyribonucleotide lattices and DNA's decrease in ranking as follows: poly(rG) greater than or equal to poly(rI) greater than or equal to ssDNA greater than dsDNA greater than poly(rA) congruent to approximately poly(rU). Thus SSB-protein from Ehrlich ascites tumor differs significantly from its presumed prokaryotic analogs.     

Cloning and characteristics of recA gene in Pseudomonas aeruginosa

A recA-like gene from Pseudomonas aeruginosa was cloned and identified by means of interspecific complementation of gene recA repair defect in Escherichia coli. The gene was mapped in the PvuII-HindIII Ps. aeruginosa chromosome fragment of 1.5 kbp in length. Having been recloned in pUC18 or 19 plasmids in either of possible orientations, this fragment was shown to complement three different defects of E. coli recA mutants: in repair, recombination and SOS functions.     

Neurons of the central nervous system innervating the lips and oral area of the pond snail

By means of retrograde transport methods, CoCl2 and horseradish peroxidase, localization and morphological peculiarities of the CNS neurons, that innervate lips and oral area, have been studied in the pond snail (Gastropoda). The neurons, sending their processes into the anterior and middle labial nerves, are found nearly in all ganglia of the parapharyngeal nervous ring on the distal and ventral surface. In the cerebral ganglia they situate as several symmetrical groups. Among the neurons revealed, there are cells with rather local distribution of the terminal branches of the processes in the CNS neuropil and neurons with vast branching areas in the neuropil not only of its own ganglion, but also of the neighbouring ones. The problem concerning the zones of possible intersensory interaction in the cerebral ganglia is discussed and presence in them, together with complex reflectory arches, of bisegmental reflectory arches is considered.     

Structural analysis of alphoid DNA of primates. II. Evolution and possible origin of alphoid DNA of primates

A computer analysis of human and primate alphoid DNA was performed. The number and localization of short inverted complete repeats within alphoid DNA dimers (but not monomers) remain conserved. Thus, in spite of high heterogeneity of the primary structure the conserved secondary structure of alphoid DNA might be functionally important. The analysis of internal periodicity of the monomeric sequences of human and primate alphoid DNA revealed its potential ancient sequence, that is a simple satellite DNA with a reiterated heptanucleotide TGAAAAA, which is suggested to be the ancestor of satellite DNase of rodents. The facts reported propose the ancient origin and possible functional role of alphoid-like DNA as a universal pericentromeric superfamily of DNA.     

Analysis of ribonucleoproteins of influenza virus containing genomic and complementary RNA

The density and sedimentation characteristics of ribonucleoproteins (RNP) containing genomic RNA from influenza virus and RNA complementary have been studied. Radioactive RNA from infected cells has been used for analysis. RNA classes of interest were isolated by reannealing with abundant nonradioactive genomic and complementary RNA and separation of resulting duplexes in electrophoresis. The RNP containing antigenomic virus-specific RNA are practically identical to "genomic" RNP for their sedimentation and density characteristics. The "plus" RNP is characterized by the stoichiometric mode of RNA protein interaction.     

Magnetic interaction of manganese with pheophytin anion-radical and chlorophyll cation-radical in reaction centers of the photosystem II

The influence of Mn on saturation curves of ESR spectra of Ph(-) and P(+)(680) at 1-200K in samples with different content of Mn has been studied. An analysis of these data and those on photoinduced changes of fluorescence yield of chlorophyll leads to the conclusion that the Mn-containing centre in Photosystem 2 is a cluster of 4 Mn atoms, two of which can be replaced by Mg(2+) or any other divalent metal. The distances between Mn Na Ph as well as between Mn and P(680) have been estimated.     

Electron microscopic study of the cytoskeleton of human podocytes

The ultrastructural study of man's cytoskeleton of podocytes is carried out. Populations of podocytes with two different types of structure of the cytoskeleton in dependence on age (2, 4, 6, 37 and 65 years) is revealed in kidneys. The first type of cytoskeleton of the podocyte is peculiar for children's age and is characterized by branched, high density microfilament network, expressed by system of microtubules and single myofilaments. The intermediate filaments here are either utterly absent or present so feebly they find themselves "disguised" by other strongly developed components of cytoskeleton and revealing them with the help of technique of electron microscope is impossible. In kidneys of adults, and especially of old aged persons podocytes with other type of organization of the cytoskeleton are mainly identified. The distinctive signs of the last are bundle arrangement of microfilaments, plural bundles of intermediate filaments and individual microtubules. This study permits to make a conclusion that during individual development and growing old in kidneys of high animals and man, probably, physiological changes causing morphological reconstruction of cytoskeleton which is accompanied by intensive development of intermediate filaments' system with simultaneous "involution" of microtubules and microfilaments' systems take place.     

Highly selective labeling of the E. coli RNA-polymerase promoter complex with reactive derivatives of oligonucleotide primers of various specificity

A technique of highly selective affinity labelling, which includes covalent modification of the enzyme-T7A2 promoter complex with reactive oligonucleotide derivatives and subsequent elongation of the attached oligonucleotide residue with a radioactive substrate was used to study the product-binding site of E. coli RNA polymerase. Different oligonucleotides complementary to the T7A2 promoter (with lengths ranging from 2 to 8 residues) containing 5'-terminal phosphorylating, alkylating or aldehyde groups were used for the labelling. The procedure resulted in labelling DNA and beta-, beta'- or sigma-subunits of the enzyme, which are therefore believed to contact with growing RNA in the course of initiation. Consideration of the labelling patterns as a functions of the oligonucleotide's length as well as of the structure and chemical specificity of the reactive groups led to a tentative topographic scheme of the RNA polymerase product-binding region.