[Computational genome analysis of three marine algoviruses].

Computational analysis of genomic sequences of three new marine algoviruses: Tetraselmis viridis virus (TvV-S20 and TvV-SI1 strains) and Dunaliella viridis virus (DvV-SI2 strain) was conducted. Both considerable similarity and essential distinctions between studied strains and the most studied marine algoviruses of Phycodnaviridae family were revealed. Our data show that the tested strains are new viruses with the following features: only they were isolated from marine eukaryotic microalgae T. viridis and D. viridis, coding sequences (CDSs) of their genomes are localized mainly on one of the DNA strands and form several clusters with short intergenic spaces; there are considerable variations in genome structure within viruses and their strains; viral genomic DNA has a high GC-content (55.5 - 67.4%); their genes contain no well-known optimal contexts of translation start codones, and the contexts of terminal codons read-through; the vast majority of viral genes and proteins do not have any matches in gene banks.

[Detection of viral infection pathogens in medicinal plants grown in Ukraine].

Monitoring of viral infection on medicinal plant plantations is carried out. Panax ginseng C.A. Meyer, Valeriana officinalis L., Plantago major L. with symptoms of viral infection were revealed. Viral nature of symptoms was proved with biotesting method. Morphology and sizes of virus particles, detected in Panax ginseng method. Morphology and sizes of virus particles, detected in Panax ginseng C.A. Meyer, Valeriana officinalis L., Plantago major L., were determined with electron microscopy method. The paper is presented in Ukrainian.

[Use of immunoenzyme analysis on nitrocellulose membranes for assessing different methods of purifying the yellow mosaic virus of beans]. / Ispol'zovanie immunofermentnogo analiza na nitrotselliuloznykh membranakh dlia otsenki razlichnykh sposobov ochistki virusa zheltoi mozaiki fasoli.

The comparative study of different methods for the purification of bean yellow mosaic virus isolated from lupine has been made. To evaluate the method of purification, electron-microscopic, spectrophotometric and ELISA techniques have been used. The possibility of using ELISA on nitrocellulose filters with the utilization of a peroxidase-antiperoxidase complex, manufactured in the USSR, for the determination of viral carriership in plants has been shown.

[Diagnosis of viruses infecting essential-oil plant crops by using immunoenzyme analysis]. / Diagnostika virusov, porazhaiushchikh éfiromaslichnye kul'tury, s pomoshch'iu immunofermentnogo analiza.

The use of the EIA point technique permitted the detection of viruses affecting essential-oil plants. The method is simple, highly specific, sensitive and can be used for checking seedlings prior to planting.

[Isolation and purification of virus damaging sunflower]. / Vydilennia ta ochystka virusu, shcho soniashnyk.

A procedure has been developed for purifying intact virus's isolate particles evoking yellow spot mosaic disease in sunflower. Purification of pathogen in 0.1 M sodium phosphate buffer, pH 8.0 containing 0.05 M Na3SO3 and 0.2% 2-mercaptoethanol is used. After first clarification extract was exposed to two cycles of high-speed centrifugation and fractionated in linear 10-40% (wt vol-1) sucrose density gradient. Virus was recovered from appropriate fractions after dialysis against 0.01 M Na2SO3.

[Physico-chemical properties of there phages of Pseudomonas syringae]. / Fiziko-khimichni vlastyvosti tr'okh fahiv Pseudomonas syringae.

The properties of DNA for 9B, 123, 788/8 phages lysing phytopathogenic Pseudomonas syringae bacteria have been analysed with results presented. It was ascertained that their genomes consist of GC-type two-chain DNA molecules having molecular weight 14-15 mDa. It was shown that sedimentation coefficient for all three phage DNA is identical and equals 26S. GC-base percentage was calculated for the phage genomes. Its value, according to results of sedimentation analysis and melting temperature, was the same for 9B (51%, 57%) and 123 (51%, 57%) and differed for 788/8 (53%, 60%). The molecular weight of DNA phages calculated from the sum of fragments, obtained after genome splitting with restriction endonucleases is in agreement with the data of sedimentation analysis. The distribution of phage DNA fragments if electrophoregrams suggests the presence of numerous common restriction sites in the phages' genomes.

[An analysis of the cDNA nucleotide sequence for the C-terminal fragment of the coat protein in tobacco mosaic virus isolates from tobacco growing in an ecological niche of Polesye, Ukraine]. / Analiz nukleotidnoi posledovatel'nosti kDNK dlia C-kontsevogo fragmenta belka obolochki VTM-izoliatov tabaka, proizrastavshego v ékologicheskoi nishe Poles'ia Ukrainy.

Two identical strains of tobacco type TVM have been isolated in the region with 137Cs nuclear contamination with density of 12.6 Cu/km2 recombinant plasmids (pTVM9, pTVM9,5) containing cDNA of complete provirus and C-end sequence of cDNA of specific capsid protein from one of isolated viruses have been obtained. The capsule proteins of isolated strains have the higher 19.5 +/- 1.9 kDa molecular weight than standard TVM strain (17.5 kDa) as to SDS-PAAG electrophoresis data. No differences in distribution of fragments immunoactive to control antiserum have been found when using immunoblot analysis of capsid proteins of isolates and standard strain treated by tripsin. Sequencing analysis of cDNA pTVM9,5 has revealed non-conservative amino acid replacement of serine by tyrosine in position 149 for homologous region of capsid protein of standard TVM strain, which allows to suppose the mediated effect of specific ecological situation on the appearance of such replacement.

[The properties of the proteins and nucleic acids of 3 Pseudomonas syringae phages]. / Deiaki vlastyvosti bilkiv i nukleinovykh kyslot tr'okh fahiv Pseudomonas syringae.

The 9B, 123, 788/8 Pseudomonas syringae phages were investigated. PAAG electrophoretic profiles of phage proteins were identical for all three phages except the minor polypeptide having molecular weight 35,000 Da. The band corresponding to this protein was present only in 9B and 788/8 phage protein profiles. Amino acid composition of phage proteins varied insignificantly showing prevalence of Asp, Glu, Ala, Leu. Phage DNA fragments electrophoresis, carried out after processing with specific endonuclease Hind III, made it possible to evaluate common restriction sites in phage genomes. Genome molecular weight was equal to 15 mda for 9B phage and to 14 mDa for 123 and 788/8 phages. The analysis of phage growth cycle showed that latent period consisted of 50 min at 20 degrees C and the yield equalled to 70 virions per infected bacterium cell. The similarity of the phages' features suggests their broad spreading in the environment.

[Use of atomic force microscopy to study the morphology and structure of viruses]. / Ispol'zovanie metoda atomno-silovoi mikroskopii dlia issledovania morfologii i strukturnoi organizatsii virusov.

The paper describes AFM methodic approaches in the investigation of viruses (TMV, phage T4). A possibility is shown to use this method to obtain high-quality three-dimensional image of objects without additional treatment with salts of heavy metals. The phage T4 was also a model to study the object density, using the phase shift of the AFM. Such researches can determine the internal structure of a virion and folding of nucleic acid inside a virion.