FIG 8.

B. thetaiotaomicron lipid A is deacylated by PGN_1123. (A and B) Lipid A structure of B. thetaiotaomicron with empty plasmid vector pSJ46 (A) or PGN_1123-expressing plasmid pSJ836 (B) as detected by MALDI-TOF MS in negative-ion mode. (C) HEK293 cells expressing TLR4/MD-2 were stimulated with B. thetaiotaomicron(pSJ46) or B. thetaiotaomicron(pSJ836) intact bacterial cells. Fold NF-κB stimulation of infected cells relative to an unstimulated control is plotted on the y axis. The results are means ± SD for triplicate samples from one of two independent experiments. Asterisks denote a significant decrease in fold NF-κB stimulation relative to that for B. thetaiotaomicron(pSJ46) (P < 0.01 by 2-tailed unpaired t tests).