ABSTRACT
DNA analysis was used to determine heritability of the cystic fibrosis in the family in risk of this disease. It enabled to detect carriers of the cystic fibrosis gene in the examined family and created a basis of the early prenatal diagnosis in case of the planned pregnancy.
Subject(s)
Cystic Fibrosis/diagnosis , DNA/genetics , Polymorphism, Restriction Fragment Length , Child, Preschool , Cystic Fibrosis/genetics , Genetic Carrier Screening , Humans , MaleSubject(s)
DNA/genetics , Genetic Diseases, Inborn/diagnosis , DNA Restriction Enzymes , Genetic Markers , HumansABSTRACT
1. The novel aminoglycoside antibiotic apramycin is shown to be a potent inhibitor of protein synthesis in bacteria both in vivo and in vitro. 2. In cell-free systems from Escherichia coli programmed with poly(U), apramycin induces translation errors, as assayed by incorporation of leucine, isoleucine and serine, although this effect occurs only to a limited extent. 3. Apramycin inhibits the translocation step of protein synthesis both in vivo, in protoplasts of Bacillus megaterium, and in vitro, in cell-free systems from E. coli. It is proposed that this is the primary inhibitory effect of the drug.
Subject(s)
Anti-Bacterial Agents/pharmacology , Bacterial Proteins/biosynthesis , Escherichia coli/metabolism , Nebramycin/pharmacology , Bacillus megaterium/metabolism , Hygromycin B/pharmacology , Leucine/metabolism , Nebramycin/analogs & derivatives , Poly U/metabolism , Protein Biosynthesis/drug effects , Protoplasts/metabolism , Puromycin/pharmacologyABSTRACT
O-Methylhydroxylamine (methoxyamine) was used for selective modification of cytosine residues in Escherichia coli 16-S rRNA. It was shown that cytosines accessible for methoxyamination are randomly distributed along the 16-S rRNA chain. Preparations of methoxyaminated 16-S rRNA, containing 2--130 modified cytosines/chain, still retained the ability to bind 30-S proteins, but the physical assembly of reconstituted particles was incorrect. The protein compositions of the reconstituted and native particles did not differ qualitatively from each other. However, the amount of protein in reconstituted particles decreased with an increasing number of methoxyaminated cytosines in 16-S rRNA. The particles obtained sedimented slower than native 30-S subunits, lost their ability to associate with 50-S ribosomes and to bind native phage f2 RNA. In contrast, modification of 16-S rRNA did not affect binding of poly(U) by reconstituted particles.
