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Biomedical subjects

P Donini

Publications and source records attributed to P Donini.

At least 55 records · Page 3Linked to original sources
PubMed1970

Amino acid control over deoxyribonucleic acid synthesis in Escherichia coli infected with T-even bacteriophage.

Starvation for a required amino acid of normal or RC(str)Escherichia coli infected with T-even phages arrests further synthesis of phage deoxyribonucleic acid (DNA). This amino acid control over phage DNA synthesis does not occur in RC(rel)E. coli mutants. Heat inactivation of a temperature-sensitive aminoacyl-transfer ribonucleic acid (RNA) synthetase similarly causes an arrest of phage DNA synthesis in infected cells of RC(str) phenotype but not in cells of RC(rel) phenotype. Inhibition of phage DNA synthesis in amino acid-starved RC(str) host cells can be reversed by addition of chloramphenicol to the culture. Thus, the general features of amino acid control over T-even phage DNA synthesis are entirely analogous to those known for amino acid control over net RNA synthesis of uninfected bacteria. This analogy shows that the bacterial rel locus controls a wider range of macromolecular syntheses than had been previously thought.

Amino Acids↗
PubMed1970

Genetic map of bacteriophage alpha.

Temperature-sensitive mutants of phage alpha were obtained by means of various mutagens and assigned to 25 complementation groups. Temperature-sensitive mutants belonging to 21 complementation groups and a mutant giving turbid plaques were used to perform two- and three-factor crosses. Seventeen of the cistrons and the turbid mutant were shown to belong to the same linear linkage group, which showed no signs of circularity. The remaining four unlinked cistrons showed peculiarities in their recombination properties. Genes which are known to be expressed earlier apear to be grouped together in a terminal segment of the linkage group.

Bacillus megaterium↗
PubMed1967

Chronology of viral functions in bacteriophage alpha.

Temperature-sensitive mutants of phage alpha were subjected to short pulses of permissive temperature at various times during the lytic cycle. All the mutants showed an optimal response to the permissive pulse at a specific time after infection. The optimal responses of the mutants belonging to the same complementation group fell close together in the same time interval; the optimal responses of mutants contained in 20 different complementation groups were more or less uniformly scattered throughout the lytic cycle. Temperature sensitivity, therefore, seems to afford, at least in the case of phage alpha, an independent way of grouping the genes in an ordered sequence with respect to the steps they control.

Bacillus megaterium↗