PMID:4275917

Citation	Sakaki, Y, Karu, AE, Linn, S and Echols, H (1973) Purification and properties of the gamma-protein specified by bacteriophage lambda: an inhibitor of the host RecBC recombination enzyme. Proc. Natl. Acad. Sci. U.S.A. 70:2215-9
Abstract	Previous experiments have indicated that the gam gene of bacteriophage lambda 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 ("gamma-protein") and that characterize the inhibition reaction with highly purified preparations of gamma-protein and RecBC DNase. Genetic characterization was performed with partially purified fractions prepared from cells infected with various lambda 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 gamma-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 lambda development.
Links	PubMed PMC433704
Keywords	Adenosine Triphosphatases/antagonists & inhibitors; Centrifugation, Density Gradient; Chromatography; Chromatography, DEAE-Cellulose; Chromatography, Gel; Coliphages/analysis; Coliphages/metabolism; DNA, Bacterial/metabolism; DNA, Circular/metabolism; DNA, Viral/metabolism; Deoxyribonucleases/antagonists & inhibitors; Escherichia coli/enzymology; Exonucleases/antagonists & inhibitors; Mutation; Recombination, Genetic; Viral Proteins/biosynthesis; Viral Proteins/isolation & purification; Viral Proteins/pharmacology
edit table

Annotations

Gene product	Qualifier	GO Term	Evidence Code	with/from	Aspect	Extension	Notes	Status
LAMBD:GAM		GO:0060703: deoxyribonuclease inhibitor activity	ECO:0000315:		F		Figure 2 provides the evidence that "product of the gam gene of phage lambda (gamma protein) is probably itself an inhibitor of the RecBC DNase".	complete CACAO 6233
LAMBD:GAM		GO:0060703: deoxyribonuclease inhibitor activity	ECO:0000314:		F		Figure 3: "The gamma protein was purified on the basis of its capacity to inhibit the ATP-dependent, double-strand exonuclease activity of the RecBC DNase.In the presence of inhibitor, the nuclease reaction proceeded at a constant, but reduced rate throughout the time of incubation due to the presence of inactive gamma protein that can compete with active material".	complete CACAO 6268
LAMBD:GAM	enables	GO:0060703: deoxyribonuclease inhibitor activity	ECO:0000315: mutant phenotype evidence used in manual assertion		F		Seeded From UniProt	complete
LAMBD:GAM	enables	GO:0060703: deoxyribonuclease inhibitor activity	ECO:0000314: direct assay evidence used in manual assertion		F		Seeded From UniProt	complete

References

See Help:References for how to manage references in GONUTS.