Showing papers by "Stuart Linn published in 1973"
TL;DR: The recBC DNase of Escherichia coli with a variety of substrates has been investigated and appears to digest linear DNA by a processive mechanism in which the rate is limited by the initiation of digestion of a molecule.
93 citations
TL;DR: Empirical experiments define the inhibitor as the protein product of the gam gene (“γ-protein”) and characterize the inhibition reaction with highly purified preparations of γ-protein and RecBC DNase and discuss their implications for regulation of genetic recombination and bacteriophage λ development.
Abstract: Previous experiments have indicated that the gam gene of bacteriophage λ is responsible for an inhibition of the RecBC DNase—an enzyme that is essential for the major host pathway of genetic recombination. We report here experiments that define the inhibitor as the protein product of the gam gene (“γ-protein”) and that characterize the inhibition reaction with highly purified preparations of γ-protein and RecBC DNase. Genetic characterization was performed with partially purified fractions prepared from cells infected with various λ mutants. An activity that inhibits RecBC DNase was absent in extracts prepared after infection by phage that carry nonsense or deletion mutations in the gam gene; this activity was highly thermolabile in an extract prepared after infection by phage that carry a temperature-sensitive mutation in the gam gene. For biochemical characterization, the γ-protein has been purified more than 800-fold. This highly purified preparation inhibited all of the known catalytic activities associated with the RecBC enzyme, but exhibited no detectable DNase or ATPase activities by itself. These findings are discussed in terms of their implications for regulation of genetic recombination and bacteriophage λ development.
72 citations
TL;DR: T7 phage resists Escherichia coli B host-controlled modification and restriction in vivo, but its DNA carries roughly five sites which are susceptible to the purified enzymes as discussed by the authors.
Abstract: T7 phage resists Escherichia coli B host-controlled modification and restriction in vivo, but its DNA carries roughly five sites which are susceptible to the purified enzymes.
29 citations