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D Freifelder

Publications and source records attributed to D Freifelder.

At least 19 recordsLinked to original sources
PubMed1977

Circular dimers of a lambda DNA in infected, nonlysogenic Escherichia coli.

Covalently closed circular dimers of phage lambda DNA have been found in Escherichia coli infected with lambda. These dimers can be formed by either the lambda Red or Int systems, by a nonrecombinational replicative mechanism requiring the activity of the lambda O and P genes or by joining of the cohesive ends. Dimers mediated by the E. coli Rec system have not been observed. Those formed by the Int system often result from recombination between different DNA molecules; however, the Red-mediated dimers may be a result of replicative extension of a single DNA molecule. Trimers have also been observed but studied only briefly.

Coliphages↗
PubMed1976

New types of Escherichia coli recombination-deficient mutants.

A set of Escherichia coli mutants deficient in intramolecular recombination and different from those previously found is described. All have temperature-sensitive lethal mutations. The mutants have been characterized with respect to the following properties: the Pap phenotype, deoxyribonucleic acid synthesis, sensitivity to ultraviolet light, ability to support the growth of phage lambda, filament formation, and mutation frequency.

Coliphages↗