Biochemical characterization of Bifidobacterium bifidum peptidoglycan d,l-endopeptidase BbMep that generates NOD2 ligands†

Abstract

Soluble peptidoglycan fragments produced by the gut bacteria are key effectors in microbiota–host crosstalk. Here, we biochemically characterized BbMep, an NlpC/p60 domain-containing peptidoglycan D,L-endopeptidase from Bifidobacterium bifidum, which efficiently digests Lys- or Orn-type sacculi. Digestion of human stool-derived muropeptides by BbMep enhances NOD2 activation.