What other methods exist for removal E. coli endotoxin from recombinant proteins?

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Manuele Martinelli

Dear Christopher Mayhugh

there are several different approaches eg

- anionic exchanger

- resins with imobilized pollylisine (https://www.thermofisher.com/order/catalog/product/88276)

- https://shop.pall.com/us/en/laboratory/sterile-filtration-clarification/endotoxin-removal/zidgri78lpj?CategoryName=endotoxin-removal&CatalogID=laboratory&tracking=searchterm:

those expoits the negative charge of endotoxins that are suggested ro work well for this purpose.

However in some cases, if protein has also low pI and therefore negative charge at the pH of storage, this kind of resins may also retain a fraction of the protein.

In the past i used the endrotrap coloumns, which exploit the ability of a phage proteijn to bind the endotoxins and i found that those works quite well.

https://lionex.de/product/endotoxin-removal-resin/

at the following link on my blog (ProteoCool) you can find a video with some more informations about it:

https://www.blogger.com/video.g?token=AD6v5dxH8C24MEVE3WeRtx3990oajft5Hx-EN9YY8MBGPYAa132ypA4B0W5d9qvnatKEYcuasGG9YyUU5ctvVqTlI-pPHsdq2MVy9uorWcnUZ8Dp-FIT-Xhf-Q-MB9w6iAIwCLpTuSqh

best regards

Manuele

Omar Gonzalez-Ortega

All gels with grafted groups (hydrophobic, ion exchange, polylysine, etc.) must be tested for the particular protein. If the use of triton X-114 (and high temperature) is not a problem, Triton X-114 is pretty efficient for endotoxin removal upon phase partitioning.