Figure 5
The effect of deletion or overexpression of hflKC on λ lysogeny and on the stability of CII: A summary of results and possible mechanisms. (A) A summary of results published previously as well as reported in this study is shown schematically. Some unanswered questions that remain are highlighted in the boxes. (B) Mechanisms for the stability of CII and the lysogenic outcome under various conditions are shown. HflB acts upon CII to digest CII, as indicated by the arrow. This digestion is inhibited by HflKC, by CIII or by the postulated CII-stabilizing factor CSF. The levels of inhibition are denoted by the lengths of the blunt lines. Possible crosstalk between HflKC and CIII or CSF are indicated by curved arrows. Dashed arrows denote lack of crosstalk. HflKC, CIII or CSF inhibits the digestion of CII. In wild type E. coli cells, this inhibition is unable to sufficiently stabilize CII, leading to normal plaques (left panel). When HflKC is overexpressed, CII is stabilized better by the action of HflKC, and turbid plaques are produced (middle panel), while in Δ hflKC cells, CIII and/or CSF act better to stabilize CII, giving rise to turbid plaques (right panel).