The bacterial mutant inf-3 (lambda) is not inducible and does not form filaments following @entity6244 starvation. Lysogenic induction is neither produced by ultraviolet light (UV) nor promoted by tif-1. This phenotype is due to a mutation infA3 located between 60 and 73 min on the @entity2624 map. The inf mutant is resistant to X-ray and UV irradiation, in contrast to all other known non-inducible bacterial mutants. It is Rec+ and able to perform host cell reactivation as well as UV-reactivation of @entity5999 . After exposure to UV light, its DNA is degraded more than that of the parent and the resumption of DNA synthesis is delayed by 30 min; nevertheless, the cell survival is analogous to that of the parent. The inf mutant is also resistant to @entity6244 starvation, for at least 3 hours. Wild type @entity5999 forms clear plaques on a lawn of non-lysogenic inf bacteria; a corresponding low level of lysogenization is found. The capacity of inf bacteria to reproduce phages lambda, T4 or T6 is impaired. No gross defect in DNA transcription has been detected. Nevertheless, this mutant might have a slight alteration in the transcription process or in any other process involved in gene expression. This alteration might affect the regulation of DNA replication and cell division as well as prophage lambda induction.

XXXX inf: a mutant deficient in prophage lambda induction and cell filamentation.

@entity5999 :: ('10710', 'Species') :: ['phage lambda'] @entity2624 :: ('83333', 'Species') :: ['E. coli K12'] @entity6244 :: ('MESH:D013941', 'Chemical') :: ['thymine']
@entity2624 :: (83333,Species) :: ['E. coli K12']
