HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via CrossRef Citing Articles via Google Scholar Google Scholar Articles by Mufti, S. Search for Related Content PubMed PubMed Citation Articles by Mufti, S. Agricola Articles by Mufti, S.

A Bacteriophage T4 Mutant Defective in Protection Against Superinfecting Phage

Molecular Biology Program Department of Microbiology Arizona Medical Center Tucson, Arizona 85724 U.S.A.

When Escherichia coli is infected by bacteriophage T4 and after a few minutes superinfected by additional phage, the secondary phage genome is prevented from being expressed and from contributing genetic information to progeny phage. This phenomenon, known as superinfection inhibition, was first observed by Dulbecco (1952). Further work was carried out by Graham (1953) and has been reviewed by Adams (1959) and Campbell (1967). Several questions have arisen concerning the mechanism of this phenomenon. Is the DNA of the superinfecting phage broken down by the DNases present in the cell, and is this DNA degradation essential for the inhibition? Is there a barrier at the membrane level which prevents the superinfecting DNA from getting into the cell? Does superinfection inhibition depend on the expression of a function or functions by the primary phage which exclude the superinfecting phage? Graham (1953) using high streptomycin concentrations to inhibit nuclease action observed that superinfecting phage were nevertheless excluded.

Received 9 May 1972; accepted 20 June 1972.