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Monofunctional platinum compound [Pt(dien)Cl] Cl and high-affinity antibodies against DNA-[Pt(dien)Cl]Cl were suggested for non-radioactive hybridisation analysis of DNA. The simple labelling procedure was based on mixing the reagents followed by the incubation for 2 h at 60 degrees C. The sensitivity and specificity of the technique were sufficient to detect 10 fg DNA in dot-hybridisation without cross-reaction with 10-fold excess of a heterologous DNA. This technique permits genome libraries screening.

A new reagent, polyphotobiotin (PPhB), for labelling DNA probes has been obtained using low molecule oligoethylenimine (M 600 Da). Photoreactive group of PPhB is 4-azido-salicylic acid. The procedure is simple and quick, the reaction time being about 20 min. PPhB-labelled DNA has the same efficiency in the hybridisation analysis as DNA labelled with Bio-4-dUTP via PCR.

DNA modified by trans diaminedichlorplatinum-II (transDDP) has been suggested as an effective probe for non-isotopic hybridization and high-specific anti-DNA-transDDP antibodies with horse radish peroxidase or alkaline phosphotase conjugated antibodies to rabbit Ig and protein A-peroxidase - for hybrids visualization. This method allows to detect 2 pg/mm DNA.

DNA modified by trans-diamminedichloroplatinum (trans-DDP) is suggested as an effective probe for non-isotopic hybridisation. Highly specific anti trans-DDP-DNA antibodies and peroxidase-conjugated antibodies to antirabbit Ig and protein A system have been used for the hybrids visualisation. This method allows one to detect 2 pg/mm2 DNA.

Method of the latex hybridization analysis has been developed: after hybridization of NA-target with biotinylated probe visualization of hybrids was carried out using latex particles, containing fluorescent dye pyronin G and coated with streptavidin. Due to encapsulation of the fluorescent dye in polymer particles sensitivity of the analysis was increased by several orders of magnitude in comparison with methods, using fluorescently labelled probes. Possessing a number of advantages, the method yields to none of any other methods of NA hybridization analysis in sensitivity.

A two-step chemical method has been developed for the introduction of biotin and other low-molecular derivatives into DNA. The method is based on the interaction of aliphatic diamines with cytosine residues of the polynucleotide chain in the presence of sodium bisulfite with subsequent addition of biotin. DNA modified this way may be used as an effective probe for non-isotopic hybridization which can be used simultaneously with 32P-labelled probes.

Tritium labelled E. coli total tRNA and tRNAPhe are prepared by action of thermally activated tritium atoms. The preparations, having the molar radioactivity up to 3.6 Ci/mmol, are useful for functional investigations.

N-vinylpyrrolidone-N(2-hydroxy) acrylamide copolymer-modified porous glass was studied as a support for gel permeation chromatography. Influenza, Sendai, fowl plague viruses and rota-viruses were purified by chromatography on the support. As compared with Sepharose 4B the support shows better hydrodynamic properties and yields higher amounts of purified viruses. The support can be also applied to the t-RNA and ribosomes separation.

Direct RNA-protein contacts have been studied by means of ultraviolet-induced (254 nm) cross-links inside complexes of NAcPhe-tRNAPhe, Phe-tRNAPhe and deacylated tRNAPhe with poly(U)-charged 30S subunit of Escherichia coli ribosome. In the first two complexes tRNA directly contacts with the similar sets of proteins (S4, S5, S7, S9/S11; S6 and S8 are found only in the second complex). These sets are similar to that in the fMet-tRNAfMet X 30S X mRNA complex, evidencing similar disposition of tRNAs in these three complexes. 16S RNA contacts in free 30S subunit mainly with proteins S4, S7 and S9/S11. In both complexes, containing NAcPhe-tRNAPhe and Phe-tRNAPhe, 16S RNA contacts with essentially the same proteins (S4, S5, S7, S8, S9/S11, S10, S15, S16 and S17) and in the same ratio, evidencing similar conformation of 30S subunit in these two complexes. In the third complex deacylated tRNAPhe contacts with proteins S4, S5, S6, S8, S9/S11 and S15, 16S RNA-protein interaction differs from those in the first two complexes by a remarkable decrease of cross-linked proteins S8, and S9/S11 and by the appearance of a large amount of cross-linked proteins(s) S13/S14. Hence, this complex differs from the first two by conformation of 30S subunit and, probably, by disposition and/or conformation of tRNA.

A two-step chemical method of introduction of nonradioactive labels in DNA was proposed. At first step DNA is modified by succinic dihydrazide at pH 5.0 and 95 degrees C, or at pH 4.5 and 37 degrees C in presence of sodium bisulfite. Then FITC or biotin are joined to the hydrazide groups. DNA modified in this way were shown to be effective hybridisation probes.