Bio-Rad Bio-Gel P Polyacrylamide Gel - Manual (Page 10)

Fig. 3. Placement and positioning of denaturing IMAC buffers.
After buffer bottle insertion, and the cartridge lines are automatically
primed, the cartridges are ready to insert into the instrument. They are
automatically equilibrated using the buffers and the preprogrammed
methods. Insert the cartridges as described in Section 2.2 and as shown in
Figure 2. After use, the cartridges should be stored at 4°C and used within
6 months.
Section 4
GST Purification and Buffer Kits
4.1 General Buffer and Cartridge Information
The lysis and wash buffers contained in the GST kit are formulated
from sodium salts, phosphate buffers, and EDTA, and provide optimized
binding, washing, and eluting of GST-tagged proteins. EDTA is included
as a chelating compound and protects against metalloproteases, a class
of proteases that can be present in
E. coli lysates. GST fusion
proteins must be enzymatically active prior to purification. The buffers
used in this system are designed for the purification of proteins that partition
into the soluble fraction of
E. coli lysates and that have accessible, and
biologically active, GST sequence tags. Table 4 provides a list of buffer
compositions. The lysis buffer is used for sample preparations (see
Section 6) and is not used in any of the buffer bottle positions.
The GST cartridges are provided in 20% ethanol and should be stored
at 4°C prior to use. The cartridges are packed with 1 ml of Bio-Rad's
Profinity™ GST resin, and typically yield
≥
10 mg of purified protein per run
(dependent upon protein expression level and culture volume loaded). To
minimize any possibility of cross-contamination, it is suggested that
individual cartridges be dedicated to the purification of a unique
GST-tagged protein. The desalting cartridges are provided in 20 mM Bis-Tris,
pH 6.5 with 0.05% azide and can be stored at 4–22°C prior to use.
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