Peptidoglycan (murein) is the polymer of N-acetylglucosamine and N-acetylmuramic acid cross-linked by short peptides that forms the bacterial cell wall. It is a major pathogen-associated molecular pattern (PAMP) recognized by host TLR2 (intact peptidoglycan), NOD1 (meso-DAP fragments, Gram-negative), and NOD2 (muramyl dipeptide, both).
Peptidoglycan recognition is central to Innate Immunity and to Crohn's disease (NOD2 mutations).[1]Intestinal Microbiota and the Innate Immune System - a Crosstalk in Crohn's Disease PathogenesisHaag LM, Siegmund B · 2015Open reference 1 ↓
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Peptidoglycan (murein) is the polymer of N-acetylglucosamine and N-acetylmuramic acid cross-linked by short peptides that forms the bacterial cell wall. It is a major pathogen-associated molecular pattern (PAMP) recognized by host TLR2 (intact peptidoglycan), NOD1 (meso-DAP fragments, Gram-negative), and NOD2 (muramyl dipeptide, both). Peptidoglycan recognit
Peptidoglycan recognition proteins (PGRPs) kill bacteria via three metal-dependent mechanisms: oxidative stress, thiol stress, and osmotic stress. PGRPs activate metal-mediated antimicrobial pathways—a direct intersection of innate immunity and metal toxicity.
TLR2 signaling: Peptidoglycan-TLR2 activation in the esophagus drives IL-6 and il 8 production.
Metal Connection#
Peptidoglycan recognition proteins (PGRPs) kill bacteria via three metal-dependent mechanisms: Oxidative Stress, thiol stress, and osmotic stress. PGRPs activate metal-mediated antimicrobial pathways—a direct intersection of innate immunity and metal toxicity.[2]Kashyap et al. 2014 — Peptidoglycan Recognition Proteins Kill Bacteria by Inducing Oxidative, Thiol, and Metal StressDipika R. Kashyap, Minhui Wang, Li-Hung Liu et al. · 2014Open reference 2 ↓
TLR2 signaling: Peptidoglycan-TLR2 activation in the esophagus drives IL-6 and IL-8 (Interleukin-8 / CXCL8) production.[3]Esophageal microbial dysbiosis impairs mucosal barrier integrity via toll-like receptor 2 pathway in patients with gastroesophageal reflux symptomsChen S, Jiang D, Zhuang Q et al. · 2024Open reference 3 ↓
Cross-References#
- Innate Immunity—peptidoglycan as PAMP
- Toll-Like Receptors—TLR2 recognizes peptidoglycan
- Crohn's Disease—NOD2 mutations impair peptidoglycan sensing
- Lipopolysaccharide—complementary Gram-negative PAMP (TLR4)
References 3
Numbered by first appearance in the article, then reconciled with its declared source list.
- 1
Haag LM, Siegmund B (2015). Intestinal Microbiota and the Innate Immune System - a Crosstalk in Crohn's Disease Pathogenesis. Frontiers in Immunology.
- 2
Dipika R. Kashyap, Minhui Wang, Li-Hung Liu et al. (2014). Kashyap et al. 2014 — Peptidoglycan Recognition Proteins Kill Bacteria by Inducing Oxidative, Thiol, and Metal Stress. PLoS Pathogens.
- 3
Chen S, Jiang D, Zhuang Q et al. (2024). Esophageal microbial dysbiosis impairs mucosal barrier integrity via toll-like receptor 2 pathway in patients with gastroesophageal reflux symptoms. Journal of Translational Medicine.
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