Figure 7.

EspP passenger domain cleavage requires an amide at the P1 position. AD202 producing the indicated mutants was subjected to pulse-chase labeling after the addition of IPTG, and proteinase K was added to half of each sample. EspP-containing polypeptide was then immunoprecipitated with the C-terminal antipeptide antiserum. (A) Analysis of Asn¹⁰²³ mutations. (B) Analysis of mutations near the C-terminus of the passenger domain. (C) Analysis of Asn¹⁰²⁴ and Asn¹⁰²⁶ mutations. Lanes 1–4, no proteinase K added (−PK); lanes 5–8, proteinase K added (+PK).