I am using a His-GST tagged PreScission Protease (47kDa) (HRV 3C protease). I want to do ion exchange chromatography to purify my protein of interest, but I cannot find the sequence for the protease anywhere and therefore cannot work out the isoelectric point to check this won't interfere with my purification. I can only find an isoelectric point for the untagged version.
Thanks for the help!
Hi there,
Prescission protease is actually the fusion protein between GST and HRV 3C protease. You may run the generated fusion sequence in Expasy protparam to estimate the pI of the fusion. GST sequence is easily available and protease sequence is available here : https://www.uniprot.org/uniprot/P03303#PRO_0000426549
I did process the His6 tagged fusion and found a pI near to 7. It is still theoritical as the process is based on primary sequence only.
Thank you for the help!
I have actually finally found what I believe to be the sequence so I am going to add it here to help others...
Sequence:
MHHHHHHSPILGYWKIKGLVQPTRLLLEYLEEKYEEHLYERDEGDKWRNKKFELGLEF PNLPYYIDGDVKLTQSMAIIRYIADKHNMLGGCPKERAEISMLEGAVLDIRYGVSRIAYSK DFETLKVDFLSKLPEMLKMFEDRLCHKTYLNGDHVTHPDFMLYDALDVVLYMDPMCLDAFPKLVCFKKRIEAIPQIDKYLKSSKYIAWPLQGWQATFGGGDHPPKSDIEGRGPNTEF ALSLLRKNIMTITTSKGEFTGLGIHDRVCVIPTHAQPGDDVLVNGQKIRVKDKYKLVDP ENINLELTVLTLDRNEKFRDIRGFISEDLEGVDATLVVHSNNFTNTILEVGPVTMAGLIN LSSTPTNRMIRYDY ATKTGQCGGVLCATGKIFGIHVGGNGRQGFSAQLKKQYFVEKQ