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 Erskine, J. M. Search for Related Content PubMed PubMed Citation Articles by Erskine, J. M. Agricola Articles by Erskine, J. M.

Host Conversion by Prophage Lambda in a Recombination-deficient Mutant of Escherichia coli

Medical Research Council Microbial Genetics Research Unit, Hammersmith Hospital, Ducane Road, London, W.12

A recombination-deficient (rec^-) strain, AB2463, of Escherichia coli K12 yielded lysogens of two types. A rare form, AB 2463 ()(ind), differed from the usual type, AB 2463 (), in showing ultraviolet (u.v.) irradiation induction of the prophage, forming normal numbers of conjugational recombinants and displaying a u.v. response curve similar to that of the parental rec⁺ strain, AB 1157. Superinfection of the inducible form with phage 21 b2 led either to loss of the prophage or to the infrequent production of a form which was still lysogenic but no longer inducible. In both cases the bacteria regained their rec^- condition as a result of the curing treatment. The phage released from AB 2463 ()(ind) was normal . It is concluded that the rec⁺ phenotype of AB 2463 ()(ind) derives from the presence of the prophage and represents a case of host conversion. It is proposed that AB 2463 ()(ind) is doubly lysogenic for and that partial curing yields the rec^- single lysogen AB 2463 ().

^* Present address: New Zealand Dairy Research Institute, P.O. Box 1204, Palmerston North New Zealand.

Received 5 June 1968; accepted 27 February 1969.