Sep 23, 2023

Public workspacePurification of GST-tagged linear tetra-ubiquitin (4xUb)

  • 1Sascha Martens lab, University of Vienna, Max Perutz Labs - Vienna
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Protocol CitationElias Adriaenssens 2023. Purification of GST-tagged linear tetra-ubiquitin (4xUb). protocols.io https://dx.doi.org/10.17504/protocols.io.q26g7pbo1gwz/v1
License: This is an open access protocol distributed under the terms of the Creative Commons Attribution License,  which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited
Protocol status: Working
We use this protocol and it's working
Created: July 07, 2023
Last Modified: May 31, 2024
Protocol Integer ID: 84631
Keywords: GST-tagged linear tetra-ubiquitin, purification, ASAPCRN
Funders Acknowledgement:
Aligning Science Across Parkinson’s (ASAP)
Grant ID: ASAP-000350
Marie Skłodowska-Curie MSCA Postdoctoral fellowship
Grant ID: 101062916
Abstract
This protocol describes purification of GST-tagged linear tetra-ubiquitin (4xUb).
Attachments
Materials
Materials

  • pGEX-4T1 vector (RRID:Addgene #199779)
  • isopropyl β-D-1-thiogalactopyranoside (IPTG)
  • Glutathione Sepharose 4B beads (GE Healthcare)
  • 10 kDa cut-off Amicon filter (Merck Millipore)
  • Superdex 200 Increase 10/300 GL column (Cytiva)
  • SORVAL RC6+ centrifuge with an F21S8x50Y rotor (Thermo Scientific)
Lysis buffer
AB
Tris-HCl pH 7.450 mM
NaCl300 mM
MgCl22 mM
DTT1 mM
cOmplete EDTA-free protease inhibitors (Roche)
DNase (Sigma)
Wash buffer
AB
Tris-HCl pH 7.450 mM
NaCl300 mM
DTT1 mM
High salt wash buffer
AB
Tris-HCl pH 7.450 mM
NaCl700 mM
DTT1 mM
SEC buffer
AB
Tris-HCl pH 7.425 mM
NaCl150 mM
DTT1 mM
Purification of GST-tagged linear tetra-ubiquitin (4xUb)
Purification of GST-tagged linear tetra-ubiquitin (4xUb)
18h 46m
18h 46m
Linear tetra-ubiquitin fused to GST (GST-4xUb) was cloned into a pGEX-4T1 vector and is available from Addgene (RRID:Addgene #199779).
After the transformation of the pGEX-4T1 vector encoding GST4xUb in E. coli Rosetta pLySS cells, grow cells in LB medium at Temperature37 °C until an OD600 of 0.4 and then continued at Temperature18 °C .

Once the cells reached an OD600 of 0.8, induce protein expression with Concentration100 micromolar (µM) isopropyl β-D-1-thiogalactopyranoside (IPTG) for Duration16:00:00 at Temperature18 °C .

16h
Collect cells by centrifugation and resuspend in lysis buffer.
Centrifigation
Sonicate cell lysates.
Sonicate cell lysates for Duration00:00:30 . (1/2)

30s
Sonicate cell lysates for Duration00:00:30 . (2/2)
30s
Clear lysates by centrifugation at Centrifigation18000 rpm, 4°C, 00:45:00 in a SORVAL RC6+ centrifuge with an F21S8x50Y rotor (Thermo Scientific).
45m
Centrifigation
Collect the supernatant and incubate with preequilibrated Glutathione Sepharose 4B beads (GE Healthcare) for Duration02:00:00 at Temperature4 °C with gentle shaking to bind GST-4xUb.
2h
Incubation
Centrifuge the samples to pellet the beads and remove the unbound lysate.
Centrifigation
Wash the beads.
Wash
Wash the beads twice with wash buffer.
Wash the beads once with high salt wash buffer.
Wash the beads twice with wash buffer.
Incubate the beads DurationOvernight with Amount4 mL of Concentration50 millimolar (mM) reduced glutathione dissolved in wash buffer at Temperature4 °C , to elute GST-4xUb from the beads.
Incubation
Overnight
To collect the supernatant, collect the beads by centrifugation.
Centrifigation
Wash the beads twice with Amount4 mL of wash buffer, and collect the supernatant.

Wash
Pool the supernatant fractions, filter through a Thikness0.45 µm syringe filter, concentrated with 10 kDa cut-off Amicon filter (Merck Millipore), and load onto a pre-equilibrated Superdex 200 Increase 10/300 GL column (Cytiva).

Elute the proteins with SEC buffer.
Analyze the fractions by SDS-PAGE and Coomassie staining.
Analyze
Pool the fractions containing purified GST-4xUb.
After concentrating the purified protein, aliquot the protein and snap-freeze in liquid nitrogen. Store the proteins at Temperature-80 °C .