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N D Kobets

Publications and source records attributed to N D Kobets.

24 records · Page 2Linked to original sources
PubMedDate not supplied

[Affinity labeling of ribosomes from Escherichia coli with 4-(N-2-chloroethyl, N-methylamino)-benzaldehyde actyl derivatives of oligouridylates].

4-(N-2-chloroethyl-N-methylamino)-benzaldehyde acetyl derivatives of penta-., hexa, hepta-, octauridylates were used for localization of the structures organizing the mRNA-binding centre of ribosomes. These derivatives, alike free oligonucleotides, stimulate the binding of phenylalanyl-tRNA to ribosomes. Within the specific complex all the oligonucleotide derivatives alkylated the 30S ribosomal subunit. Octauridylate and hexauridylate derivatives specifically alkylated also the 50S subunit of ribosomes. Polyuridylic acid protected ribosomal subunits from alkylation. In the 30S subunit the derivatives modify 16S RNA and proteins: S4, S5, S7, S9, S13, S15, S18, S21. It was found that oligouridylate derivatives of different length alkylate different proteins.

Escherichia coli↗
PubMedDate not supplied

[Affinity labeling of the ribosomes from Escherichia coli by 4-(N-2-chloroethyl-N-methyl-aminobenzyl-5'-phosphoamide of heptauridylic acid].

4-(N-2-chloroethyl-N-methyl)aminobenzyl-5'-phosphoamide of the heptauridylic acid was used to localize the structures organizing mRNA-binding site of ribosomes from E. coli. Both rRNA and proteins undergo modification in the ribosome 10-18 and 82-90% of the total ribosomal subunit modification, respectively. Using the method of two-dimensional electrophoresis in the acrylamide gel the proteins S5, S11, S13 and L2, L7/L12, L31 which are labelled by the analog of mRNA were identified. We assume these proteins to be located in the vicinity of mRNA-binding centre of ribosomes.

Affinity Labels↗
PubMedDate not supplied

[Visualization of DNA segments, interacting with reactive oligonucleotide derivatives in interphase nuclei and metaphase chromosomes].

Reaction of (pdT)16 derivatives, bearing 4-(N-2-chloroethyl-N-methylamino)benzylphosphamide group on its 5' end and biotin on its 3' end with DNA in interphase nuclei and metaphase chromosomes has been investigated by fluorescence and electron microscopy. The result obtained evidence that in interphase nuclei DNA in active chromatin (nucleolus) is the most available for specific modification. In metaphase chromosomes the modified DNA regions are situated on the surface of chromosome.

Animals↗
PubMedDate not supplied

[Specific chemical modification of ribosomes in the vicinity of their mRNA-binding center].

4-N-2-chloroethyl-N-methylamino-benzaldehyde acetal derivatives (RCL-derivatives) of octauridylic and nanauridylic acids were used to localize the structures organizing mRNA-binding site of ribosomes. These derivatives, like free oligonucleotides, stimulate binding of 14C-phenylalanyl-tRNA to ribosomes. They effectively alkylate ribosomes within the specific complex. The extent of 30S subunit alkylations is much greater than that of 50S subunit, alkylation being completely inhibited by preincubation with polyridylic acid, suggesting that the chemical alteration occurs near mRNA-binding site. Both rRNA and proteins undergo modification in 30S subunit (75% and 25% of the total 30S subunit modification, respectively).

Binding Sites↗