PGN-ECndi ultrapure peptidoglycan

Insoluble peptidoglycan from E. coli K12

PGN-ECndi is an ultrapure preparation of peptidoglycan (PGN) from the Gram-negative Escherichia coli K12.

PGN is a major component of the bacterial cell wall. It is mainly single-layered in Gram-negative bacteria (e.g. E. coli) and multi-layered in Gram-positive bacteria (e.g. B. subtilis). PGN is a large polymeric molecule made of glycan strands connected by short peptides. PGN structure varies among bacterial species at the level of sugar polymers, and of cross-linked amino-acids. In Gram-positive bacteria, the amino-acid side chain structure consists of L-alanine, D-glutamate, L-lysine, and D-alanine. In Gram-negative bacteria, the L-Lysine is replaced by meso-diaminopimelic acid (mDAP or meso-DAP) [1].

PGN, either intact or fragmented, is sensed by the innate immune system through different PRRs (pattern recognition receptors). PGN is known to be a potent activator of NF-κB and TNF-α through TLR2, although it has been reported that PGN agonist activity for TLR2 is likely relying on other commonly co-purified molecules, such as cell wall lipoproteins and lipoteichoic acids (LTAs). The role of TLR2 in the direct recognition of PGN remains controversial, and the discrepancies among studies may arise from the purification methods as well as from the variation in PGN structure in the different bacterial species [1-4].

PGN-ECndi ultrapure from E. coli K12 is an insoluble preparation of PGN purified by detergent lysis and hydrolysis under basic conditions to eliminate lipophilic constituents. This PGN preparation does not activate TLR2-transfected HEK293 cells, but it still activates NOD1- and NOD2-transfected cells. 

Key features of PGN-ECndi:

• Ultrapure preparation of peptidoglycan from Escherichia coli K12
• Insoluble
• Functionally-tested using cellular reporter assays
• NOD1 and NOD2 agonist

References:

1. Wolf A.J. & Underhill D.M., 2018. Peptidoglycan recognition by the innate immune system. Nat. Rev. Immunol. 18(4):243-254.
2. Travassos.LH. et al., 2004. Toll-like receptor 2-dependent bacterial sensing does not occur via peptidoglycan recognition. EMBO Rep. 5(10):1000-1006.
3. Girardin SE et al., 2003. Peptidoglycan molecular requirements allowing detection by Nod1 and Nod2. J Biol Chem. 278(43):41702-8.
4. Dziarski R., 2004. Peptidoglycan recognition proteins (PGRPs). Mol Immunol. 40(12): 877-86.

Specifications

Specificity: NOD1/NOD2 agonist

Working Concentration: 1 - 10 µg/ml

Resuspension: 200 μg/ml in water. Note: PGN-ECndi ultrapure is insoluble. The suspension appears hazy.

Quality control:

• The biological activity of PGN-ECndi has been verified using HEK-Blue™ hNOD1 cells and HEK-Blue™ hNOD2 cells.
• The absence of bacterial contaminants has been confirmed using HEK-Blue™ hTLR2 cells (for lipoproteins) and HEK-Blue™ hTLR4 cells (for endotoxins).

Contents

PGN-ECndi is provided as a lyophilized white solid.

• 5 mg insoluble peptidoglycan from E. coli K12 (PGN-ECndi)
• 25 ml sterile endotoxin-free water

PGN-ECndi is shipped at room temperature.

Store at -20°C. Resuspended PGN-ECndi can be stored at 4°C for 1 month or at -20°C for at least 6 months.

 Avoid repeated freeze-thaw cycles.