RESUMO
Four octapeptides containing the dipeptide fragments of the lac-repressor primary structure have been synthesized. The general scheme of synthesis consisted in the preparation of tetrapeptides using successive elongation from the C-terminus by the mixed anhydride method followed by their condensation into octapeptides.
Assuntos
Oligopeptídeos/síntese química , Proteínas Repressoras , Fatores de Transcrição , Sequência de Aminoácidos , Fenômenos Químicos , Química , Oligopeptídeos/genéticaRESUMO
A BamHI DNA fragment of 301 bp corresponding to the main repeating unit of 5S rRNA was isolated from barley genomic DNA. The primary nucleotide sequence of this fragment was determined and a high level of homology was found between coding sequences of 5S rRNA genes of barley, wheat and rye. At the same time, spacer's nucleotide sequences of different species of cereals were changed dramatically. At least two types of 5S rRNA tandem repeats of 301 and 450 bp were found in barley genome. Polymorphism for restriction fragment length in 5S rRNA repeats allowed to discriminate between all barley varieties used in this work.