FIG 1.
EatA degrades the major intestinal mucin MUC2. (a) EatA is a serine protease autotransporter protein with an N-terminal signal peptide (SP) passenger domain containing the predicted HDS catalytic triad and C-terminal β-domain required for extracellular secretion of passenger domain. (b) Immunoblot showing the degradation of MUC2 (black arrow) in lysates of LS174T cell monolayers treated with recombinant EatA passenger domain (rEatAp) compared to mock (ø) treatment. The positions of molecular mass markers (in kilodaltons) are indicated to the left of the blot. (c and d) Abundant cell-associated MUC2 (green) on the surfaces of mock-treated LS174T cells (c) is depleted following the addition of recombinant rEatAp passenger domain (d). Shown at the left of each panel are individual z-stack images, while composite yz and xz reconstructions are shown to the right and at the bottom of each panel, respectively. Nuclei are stained blue, and cell membranes are shown in red.