title: Stationary phase-like properties of the bacteriophage lambda Rex exclusion phenotype.
abstract: The rex genes of bacteriophage lambda were found to protect lysogenic Escherichia coliK host cells against killing by phage T4 rII, when compared in parallel to isogenic Rex(-) lysogens and nonlysogens. This protective effect was abrogated upon mutation of the host stationary-phase sigma factor RpoS. Rex(+) lysogens infected by T4 rII contracted, formed aggregates and shed flagella, thus resembling cells entering stationary phase. These phenotypes were accentuated in nonlysogenic cells carrying multicopy plasmids expressing rexA-rexB: cells were about two-fold contracted in length, expressed membrane-bound and detached flagella, were insensitive to infection by a variety of phages and clumped extensively; in addition, cultures of these cells were odorous. Our observations support the hypothesis that the Rex system can cause a stationary-phase-like response that protects the host against infection by T4 rII.
authors.affiliation: Department of Microbiology and Immunology, College of Medicine, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5E5, Canada.
authors.forename: R A
authors.initials: RA
authors.lastname: Slavcev
authors.forename: S
authors.initials: S
authors.lastname: Hayes
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics; D017122:Bacteriophage T4 / Q000235:genetics; D010582:Bacteriophage lambda / Q000235:genetics* / Q000254:growth & development* / Q000648:ultrastructure; D002472:Cell Transformation, Viral; D002874:Chromosome Mapping; D004926:Escherichia coli / Q000235:genetics; D015870:Gene Expression; D005814:Genes, Viral; D016355:Genes, pX / Q000235:genetics; D008242:Lysogeny; D009154:Mutation; D010641:Phenotype; D010957:Plasmids; D012808:Sigma Factor / Q000235:genetics; D013696:Temperature
chemical_list: D001426:Bacterial Proteins; D012808:Sigma Factor; C069567:sigma factor KatF protein, Bacteria