[Identification of cyanobacteria from genus Anabaena isolated from the rhizosphere of cotton-plant].

Identification of nucleotide sequence of the gene 16S rRNA of cyanobacteria Anabaena variabilis str.21 (Uzb1) exhibits that the strain from root sphere of cotton plants is 99% homologous to a known strain of Anabaena variabilis (EF488831.1). This data confirms the phylogenetic relationship of the strain of cyanobacteria A. variabilis Uzb1 to other described representatives of genus Anabaena as addition to morphological characteristics (presence of akinets (spores) and heterocysts).

[Activity of phenylalanine-ammonia-lyase in callus cultures of sugar beat infected by Acholeplasma].

The effect of Acholeplasma laidlawii var. granulum 118 on activity of phenylalanine-ammonia-lyase (PAL) in callus cultures of sugar beat was researched. The optimal conditions of enzyme reaction were: using the L-phenilalanine as a substrate, pH 8.4-8.8, the temperature optimum 38-40 degrees C. It was established that at the infecting of sugar beat callus culture by phytopathogenic mollicute the PAL activity was temporarily increased and reached its maximum after 2 h of infecting. Then it gradually decreased and in 24 h reached its initial level. An increase of PAL activity of plant is considered as protective reaction in response to the action of pathogen.

[Effect of Acholeplasma laidlawii var. granulum on lectin activity of sugar beet calluses].

The dynamics of lectin activity of sugar beet calluses infected by mollicute Acholeplasma laidlawii var granulum str. 118 was studied. Activity of acid-soluble lectins of sugar beet cell cultures increased 4.5 times during some first hours after infecting by acholeplasma. At early stages of infecting by mollicute qualitative changes were also revealed in the protein spectra of acid-soluble lectins of sugar beet calluses.

[The ability of the oligodeoxyribonucleotides complementary to the 3'-terminal segment of 16s-rRNA in Mollicutes to suppress translation in their ribosomes in an in-vitro system]. / Sposobnost' oligodezoksiribonukleotidov, komplementarnykh 3'-kontsevomu uchastku 16S-rRNA mollikutov, podavliat' transliatsiiu na ikh ribosomakh v sisteme in vitro]

Effect of oligodesoxyribonucleotide, complementary to 3'-end sequence (3'-UCUUUCCUCCAC) of 16S-rRNA of mollicutes, and its phenasine derivatives on the process of translation of mollicute has been studied in the system of in vitro translation, created on the basis of ribosomes of Acholeplasma laidlawii var. granulum str. 118 and germ extracts of the wheat and optimized in respect of the temperature (23 degrees C), translation time (70 min), concentration of potassium and magnesium ions (150 and 5 mM, respectively). It is shown that acholeplasma ribosomes are most efficiently inhibited (60%) under their interaction with oligonucleotide containing one phenasine insert on the 3'-end, nonmodified oligonucleotide exerted a bit less inhibiting effect (58%). Oligonucleotide containing intercalating inserts in 3'- and 5'-positions manifested the least inhibiting effect (35%). It is noted that the efficiency translation inhibition by synthetic oligonucleotides is conditioned by nuclease activity of the system and by the length of the section of active binding of oligonucleotide with the sequence target on rRNA. It is supposed that oligonucleotides complementary to certain unique rRNA sequences can become promising highly specific drugs for prophylaxis and treatment of mycoplasmoses.

[A cell-free translation system based on mollicute ribosomes]. / Beskletochnaia sistema transliatsii na osnove ribosom mollikutov.

Active cell-free protein-synthesizing systems are created on the basis of ribosomes of Acholeplasma laidlawii var. granulum str. 118, A. laidlawii PG-8 and active lysates of eucaryotic cells (lysate of rabbit reticulocytes and wheat germ extract) in which activity of 80S-ribosomes was suppressed by addition of actidione in concentrations of 150 and 200 mkg/ml, respectively. It is shown that preincubation of active lysates of eucaryotic cells with actidione does not influence their ribosome inhibition level. It was found that the system of in vitro translation on the basis of wheat germ extract was more specific for ribosomes of phytopathogenic acholeplasmas (str. 118), while ribosomes of the saprophytic strain (PG-8) revealed no such specificity with respect to cell-free translation systems.

[The inhibitory action of 6-azacytidine on Mollicutes and its proposed mechanism]. / Ingibitornoe deistvie 6-azatsitidina na mollikuty i ego predpolagaemyi mekhanizm.

6-Azacytidine (6-AC) is shown to have an inhibitory effect on the Mollicutes of the different systematic position. The growth of type strains of Mollicutes (Acholeplasma laidlawii PG-8, Mycoplasma pneumoniae FH and M. fermentans PG-18) completely ceased in the nutrient medium at concentration of the above substance in it within the range of 125-250 micrograms/ml. 50% inhibiting concentration of 6-AC equaled: for M. fermentans PG-8: 23.43 micrograms/ml; M. pneumoniae FN: 46.8 micrograms/ml; Acholeplasma laidlawii PG-8: 62.5 micrograms/ml. 6-AC concentration 5 micrograms/ml decreased the process of DNA-dependent DNA synthesis in the in vitro system more than by 60%. 6-AC exerted less effect on the DNA-dependent RNA synthesis in the in vitro system: at different concentrations of 6-AC (up to 400 micrograms/ml) RNA synthesis decreased only by 20%. Translation on ribosomes of Mollicutes in the in vitro system completely ceased at 6-AC concentration 100 micrograms/ml. The results obtained indicate that for 6-AC in cells of Mollicutes and, possibly, for other microorganisms there are two targets: ribosomes and DNA-dependent DNA-polymerase. Total effect of blocking of the translation and replication processes by 6-azacytidine causes death of Mollicutes. Since 6-AC has no harmful effect on the human cells, it can be used as an efficient method for treatment of respiratory and urogenital diseases induced by Mollicutes.

[The isolation of ribosomes from Acholeplasma and the study of their physicochemical characteristics]. / Poluchenie ribosom akholeplazm i issledovanie ikh fiziko-khimicheskikh kharakteristik.

Ribosomes are produced from Acholeplasma laidlawii PG-8 and A. laidlawii var. granulum str. 118. It is proved as possible to use the standard method of differential centrifugation for isolation of mollicute ribosomes. The physico-chemical properties of acholesplasma ribosomes are studied. The protein content for A. laidlawii PG-8 amounted to 39.6%, rRNA content--60.4% and for A. laidlawii var. granulum--39.1 and 60.8%, respectively. The RNA: protein ratio equals 1.5:1, the ratio of optic density indicates at 260 and 280 nm--2, that is peculiar to treated preparations of ribosomes. Sedimentation coefficient of acholeplasma ribosomes is 70S. The produced preparations of acholeplasma ribosomes can be used subsequently for creating the system of translation in vitro to study the biosynthesis processes of mollicute protein.