Probing cII and himA action at the integrase promoter pi of bacteriophage lambda.
Academic Article
Overview
Research
Identity
Additional Document Info
Other
View All
Overview
abstract
Plasmids were constructed to supply cII-coded protein for activation of the phage promoter pI. Using a fusion which expresses lacZ from pI. We can accurately follow activation of pI without having to assay int activity in vivo. A large excess of cII protein compared to a normal lytic infection stimulates lacZ expression about 10-fold over the basal level. The int-c226 constitutive allele of pI is not further activated by cII even though its level of lacZ expression is less than the maximal cII-activated expression from wild type pI. A himA-deleted strain also shows activation, demonstrating that there is no absolute requirement for the himA gene product for cII-stimulated transcription at pI.