NUCLEIC ACID SYNTHESIS BY A LYSOGENIC STRAIN OF ESCHERICHIA COLI INFECTED WITH ANrII MUTANT OF COLIPHAGE T2

Abstract

Mutants of phage T2, of the group called rII mutants, are known to lack the parent phage's ability to form plaques on strains of Escherichia coli lysogenic for phage λ That they are capable of initiating desoxyribonucleic acid synthesis in the infected lysogenic host cells but are incapable of maintaining it has been shown by the present study using T2r7and -E. coli C112 (λs). In contrast with the superficially similar behavior shown by some other phages (e.g. λv1h), ultraviolet irradiation and consequent induction of the lysogenic culture do not release the prophage-linked inhibition of T2r7DNA synthesis. Net ribose-nucleic acid synthesis is stopped in all cultures on infection with T2r7.

Bacteriophate-Induced Functions in Escherichia coli K(λ) Infected with rII Mutants of Bacteriophage T4

“…Deoxycytidine triphosphatase, an early enzyme involved in phage DNA synthesis, is produced at the same rate up to about 12 min after infection of K(X) with T4r+ or T4rII phage. Phage DNA is synthesized up to 10 to 15 min in rll-infected K(X) (11,13,20). In contrast, no mature phage particles are produced, nor is any anti-phage serum-blocking antigen or phage lysozyme.…”

“…This mechanism seems to be controlled by the phage, and in time this control would belong to the late functions. In rll-infected K(X), no such mechanism seems to operate (9,20).…”