Summary
Two distinct phases characterized by different levels of immunity that appear in some E. coli strains lysogenic for reduced immunity mutants of bacteriophage lambda are identified as single and tandem double lysogens respectively on the basis of DNA-DNA hybridization experiments and the requirement of the phage xis function for the transition from a single to a double, and of the host recA function for the transition from a double to a single lysogen (in a xis - condition). Rim lysogens with a further increase in immunity, containing some 5 copies of the lambda genome per host genome, have also been observed.
It is argued that the different levels of immunity are a direct reflection of the CI gene dosage effect.
An unexplained finding is that rim single lysogens yield double lysogens with a frequency of near 1% per generation, whereas cured cells fail to appear even at a frequency 100 times lower.
Similar content being viewed by others
References
Blüthmann, H., Bruck, D., Hübner, L., Schoffski, A.: Reassoziation of nucleic acids in solutions containing formamide. Biochem. biophys. Res. Commun. 50, 91–97 (1973)
Burton, K.: Determination of DNA concentration with diphenylamine. Methods in Enzymology XII B, 163–166 (1968)
Calef, E., Avitabile, A., Guidice, L. del, Marchelli, C., Nenna, T., Neubauer, Z., Soller, A.: The genetics of the anti-immune phenotype of defective lambda lysogens. The bacteriphage lambda (A.D. Hershey, ed.). Cold Spring Harbor Laboratory, pp. 609–621 (1971)
Echols, H., Green, L.: Establishment and maintenance of repression by bacteriophage lambda: The role of the C I , C II and C III proteins. Proc. nat. Acad. Sci. (Wash.) 68, 2190–2194 (1971)
Flamm, W.G., Bond, H.E., Burr, H.E.: Density-gradient centrifugation of DNA in a fixed-angle rotor. Biochim. biophys. Acta (Amst.) 129, 310–319 (1966)
Gillespie, D., Spiegelman, S.J.: A quantitative assay for DNA-RNA hybrids with DNA immobilized on a membrane. J. molec. Biol. 12, 829–842 (1965)
Gillespie, S., Gillespie, D.: Ribonucleic acid-deoxyribonucleic acid hybridization in aqueous solutions and in solutions containing formamide. Biochem. J. 125, 481–487 (1971)
Guarneros, G., Echols, H.: New mutants of bacteriophage lambda with a specific defect in excision from the host chromosome. J. molec. Biol. 47, 565 (1970)
Imae, Y., Fukasawa, T.: Regional replication of the bacterial chromosome induced by derepression of prophage lambda. J. molec. Biol. 54, 585–597 (1970)
Kaiser, A.D.: Mutations in a temperate bacteriophage affecting its ability to lysogenize E. coli. Virology 3, 42–61 (1957)
Kourilsky, Ph., Leidner, J., Tremblay, G.J.: DNA-DNA hybridization on filters at low temperature in the presence of formamide or urea. Biochem. 53, 1111–1114 (1971)
Lieb, M.: Allosteric properties of the lambda repressor. J. molec. Biol. 39, 379–382 (1969)
Maniatis, T., Ptashne, M.: A DNA operator repressor system. Sci. Amer Jan. 1976, pp. 64–76 (1976)
Marmur, J.: A procedure for the isolation of deoxyribonucleic acid from microorganisms. J. molec. Biol. 3, 208–218 (1961)
Reichardt, L., Kaiser, A.D.: Control of lambda repressor synthesis. Proc. nat. Acad. Sci. (Wash.) 68, 2185–2194 (1971)
Steinberg, R.A., Ptashne, M.: In vitro repression of RNA synthesis by purified lambda phage repressor. Nature (Lond.) New Biol. 230, 76–80 (1971)
Strack, H.-B., Kayser, M., Holder, S.: Reduced immunity in lysogens of bacteriophage lambda due to a mutation in the prophage. Virology 48, 707–716 (1970)
Strack, H.-B., Ziegler, R.: A new class of clear mutants from coliphage 434 hy not complementing C II and C III mutants for lysogenization. Molec. gen. Genet. 106, 80–88 (1969)
Warnaar, S.D., Cohen, J.A.: A quantitative assay for DNA-DNA hybrids using membrane filters. Biochem. biophys. Res. Commun. 24, 554–558 (1966)
Weisberg, R., Gallant, J.: Dual function of the lambda prophage repressor. J. molec. Biol. 25, 537 (1967)
Author information
Authors and Affiliations
Additional information
Communicated by E. Bautz
Rights and permissions
About this article
Cite this article
Schneider, J., Strack, H.B. Analysis of the phase variation in lambda reduced immunity lysogens. Molec. gen. Genet. 151, 181–187 (1977). https://doi.org/10.1007/BF00338693
Received:
Issue Date:
DOI: https://doi.org/10.1007/BF00338693