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C Marchelli

Publications and source records attributed to C Marchelli.

5 recordsLinked to original sources
PubMed1984

Escherichia coli K-12 gyrB gene product is involved in the lethal effect of the ligts2 mutant of bacteriophage Mu.

Mu ligts2 mutants, defective for development and integration, show a high killing effect on the infected host. A number of survivors to Mu ligts2 infection were analyzed; they are characterized by nonpermissivity for both development and lysogenization of bacteriophage Mu. Bacteriophages D108 and P1 are also inhibited in these strains as is transposon Tn9. The corresponding mutation site was mapped at 82 min and identified with the Escherichia coli gyrB site.

Coliphages↗
PubMed1980

Two classes of Mu lig mutants: the thermosensitives for integration and replication and the hyperproducers for ligase.

We have previously shown that Mu restores an active DNA replication at non-permissive temperature in E. coli K12 ligts7 strains. In this paper we describe two new types of phage mutants for the Mu lig function. The Mu ligts mutants are conditional lethals defective for both integration and replication of DNA, unable to 'complement' the bacterial lig mutation; the map between B and lys. The mutants of the other type, on the other hand, are able to restore to a maximum level the activity impaired by the ligts7 mutation in the host. We suggest the hypothesis that the product of Mu lig gene could be part of a complex as a topoisomerase.

Chromosome Deletion↗
PubMed1976

Deletions induced by heat treatment of E. coli K12 lysogenic for lambda prophages.

We have investigated the production of prophage deletions in heat-induced lambda lysogens of E. coli K12. Our results are indicative of a direct action of the heat-induced prophage in producing deletions. The temperature of 40 degrees used for the experiments may be critical to prove this effect. The phage function involved in deletion formation is not known.

Chromosome Aberrations↗