FIG 1.

Tfa_Mu binds E. coli LPS and cell surface. (A) As illustrated by the diagram on the left, a Mu phage lysate was added to 50 μg of E. coli K-12 LPS alone or LPS premixed for 1 h with increasing amounts of Tfa_Mu, Tfib_Mu-C:Tfa_Mu complex, or control protein (AcrIE1). After a further 1-h incubation, the number of infective particles was determined by plaquing assays. The phage titer was normalized to an untreated lysate (left y axis) and the actual number of PFU counted is also shown (right y axis). (B) As illustrated by the diagram on the left, E. coli K-12 cells were mixed for 1 h with increasing amounts of Tfa_Mu, Tfib_Mu-C:Tfa_Mu complex, or control protein (AcrIE1), then the cells were mixed with a lysate of phage Mu. This mixture was plated and the number of resulting plaques was determined. The phage titer was normalized to that obtained on cells that were not premixed with protein (left y axis) and the actual number of PFU counted is also shown (right y axis). The values shown are the mean of three replicates with error bars representing the standard deviation. The actual reduction in PFU under conditions of maximal inhibition by Tfa_Mu protein or LPS was approximately 300-fold.