LPS-EK (LPS from E. coli K12)

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.


Working concentration: 1 ng- 10 µg/ml


TLR4 and TLR2 agonist

LPS-EK Ultrapure

TLR4 agonist


• 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 and 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.


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.


Recent articles using InvivoGen LPS-EK (LPS from E. coli K12)



Description Standard LPS, E. coli K12
Cat. Codetlrl-eklps
Unit Size5 mg
Price For price or distributor address,
please select your country

LPS-EK Ultrapure

Description Ultrapure lipopolysaccharide from E. coli K
Cat. Codetlrl-peklps
Unit Size1 mg
Price For price or distributor address,
please select your country
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Note that the sequence of available ORFs provided by InvivoGen can differ from a given reference Genbank record due to genetic variations and/or alternative splicing. Customers should verify that the version of a gene sold by InvivoGen is suitable for the customer needs.
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