LPS-EK (LPS from E. coli K12)

LPS-EK Unit size Cat. code Docs Qty Price
Standard LPS, E. coli K12
5 mg
LPS-EK Ultrapure Unit size Cat. code Docs Qty Price
Ultrapure lipopolysaccharide from E. coli K12
1 mg

Lipopolysaccharide from Escherichia coli K12

InvivoGen provides LPS-EK with two grades of purity:

LPS-EK is a standard lipopolysaccharide (LPS) preparation. It was extracted by a phenol-water mixture.

LPS-EK contains other bacterial components, such as lipopeptides, and therefore stimulates both TLR4 and TLR2.

Ultra-pure LPS-EK was extracted by successive enzymatic hydrolysis steps and purified by the phenol-TEA-DOC extraction protocol.

Ultrapure LPS-EK only activates the TLR4 pathway.

Back to the top


Working concentration: 1 ng- 10 µg/ml.

Specificity: TLR4 and TLR2 agonist.

LPS-EK Ultrapure
Specificity: TLR4 agonist.

Back to the top


  • 5 mg standard lipopolysaccharide from E. coli K12 (LPS-EK)
  • 1.5 ml endotoxin-free water


  • 1 mg ultrapure lipopolysaccharide from E. coli K12 (LPS-EK Ultrapure)
  • 1.5 ml endotoxin-free water

LPS-EK is shipped at room temperature.

LPS-EK should be stored at -20°C.
Upon resuspension, prepare aliquots of LPS-EK and store at 4°C for short term storage or -20 ̊C for long term storage.

Lyophilized product is stable 1 year at -20°C. Resuspended product is stable 1 month at 4°C and 6 months at -20°C.

Avoid repeated freeze-thaw cycles.

Back to the top


LPS-EK is lipopolysaccharide from E. coli K12. LPS is the principal component of Gram negative bacteria that activates the innate immune system.

LPS recognition is predominantly mediated by TLR4 [1]. This recognition involves the binding of LPS with lipopolysaccharide-binding protein (LBP) and subsequently with CD14 which physically associates with a complex including TLR4 and MD2 [2].

Formation of the TLR4-centered LPS receptor complex induces the production of proinflammatory cytokines through the MyD88 pathway.

LPS signaling also involves a MyD88- independent cascade that mediates the expression of IFN-inducible genes.

Most LPS preparations on the market are contaminated by other bacterial components, such as lipoproteins, thus activating TLR2 signaling as well as TLR4 signaling.

High concentrations (1 µg/ml) of the standard preparation of LPS-EK can induce TLR2 activity, whereas LPS-EK Ultrapure only activates the TLR4 pathway.

1. Poltorak A. et al., 1998. Defective LPS signaling in C3H/HeJ and C57BL/10ScCr mice: mutations in TLR4 gene. Science, 282(5396): 2085-8.
2. Shimazu R. et al., 1999. MD-2, a molecule that confers lipopolysaccharide responsiveness on Toll-like receptor 4. J Exp Med, 189(11):1777-82.
3. Netea MG. et al., 2002. Does the shape of lipid A determine the interaction of LPS with Toll-like receptors? Trends Immunol, 23(3):135-9.

Back to the top


Load more
Customer Service
& Technical Support
Shopping cart is empty