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PubMed · 5723713

Evidence for a new endonuclease synthesized by lambda bacteriophage.

R C Shuster·A Weissbach
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Abstract

Infection of nonlysogenic Escherichia coli CR34(S) (Thy(-)) with bacteriophage lambda C(I)857 resulted in the formation of twisted circular double-stranded phage deoxyribonucleic acid (DNA; species I). When such infected bacteria were incubated in the absence of thymine, there was a significant decrease in the amount of species I DNA after 60 min of incubation. A similar loss of species I lambda DNA during incubation in a thymine-deficient medium was also observed after infection of the endonuclease I-deficient strain, E. coli 1100(S) (Thy(-)). This destruction of twisted, circular lambda DNA in thymine-deprived cells did not occur in the presence of chloramphenicol nor in lysogenic E. coli CR34 carrying a noninducible lambda prophage. It is therefore concluded that the endonuclease which attacks this circular configuration of lambda DNA is newly synthesized after infection and is directed by the phage chromosome.

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Centrifugation, ZonalChloramphenicolColiphagesDNA, ViralDeoxyribonucleasesMutationThymineTritiumJournal Article

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R C Shuster, A Weissbach. 1968. Evidence for a new endonuclease synthesized by lambda bacteriophage.. https://doi.org/10.1128/jvi.2.10.1096-1101.1968

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