Anti-inflammation and adhesion enhancement properties of the multifunctional LPxTG-motif surface protein derived from the Lactobacillus reuteri DSM 8533.

LPxTG-motif protein (LMP) is one kind of a precursor protein that contains a conserved LPxTG-motif at the C-terminus, which can be recognized by sortase A (SrtA) and covalently bind to the bacterial peptidoglycan. In this study, LMP derived from Lactobacillus reuteri (L. reuteri) was heterologous expressed and the tolerance and intestinal colonization ability of the LMP on L. reuteri were analyzed in simulated gastrointestinal fluid. Meanwhile, the anti-inflammatory activity of LMP was also evaluated in the LPS-stimulated RAW 264.7 cell model. The results indicated that LMP can promote the intestinal survival rate and adhesion characteristics of L. reuteri and enhanced the autoinducer-2 (AI-2) signaling molecule of the Lactobacillus strains in quorum sensing. Furthermore, LMP can inhibit the expressions of inflammatory cytokine TNF-α and IL-1β via ERK-JNK related MAPK signaling cascades. These findings provide a better understanding of the multifunctional LPxTG-motif surface protein derived from L. reuteri in the gastrointestinal tract environment.