Figure 1. P. gingivalis strain 381 utilizes endogenous lipid A 1- and 4′- phosphatase activities to modify lipid A species and evade TLR4 activation.

Lipid A isolated from P. gingivalis wild-type strain 381 (A) or lipid A mutant strains PG1587 ₃₈₁ (B) and PG1773 ₃₈₁ (C) were examined by MALDI-TOF MS. Arrows indicate the predominant lipid A species that are expressed for each strain (A–C). The major lipid A structures examined in this study have been identified in P. gingivalis as previously described (D–G) [19].