€697.00 – €1,336.00
FabRICATOR LE (Low Endotoxin) digests IgG at a single site below the hinge
FabRICATOR LE (IdeS) is an IgG-specific cysteine protease that digests antibodies or Fc-fusion proteins at one single amino acid position below the hinge region generating Fc and F(ab’)2 fragments. FabRICATOR LE contains low endotoxin levels <0.02 EU/vial and is lyophilized for digestion of 2 – 5 mg of antibodies or Fc-fusion proteins.
| Product Group | |
|---|---|
| Source/Origin | Cloned from S. pyogenes, Produced in E. coli (His-tagged), 37.7 kDa |
| Product Composition | Lyophilized in PBS, Purified to ≥ 95% homogeneity, Contains low endotoxin levels <0.04 EU/vial |
| Digestion Site | |
| Specificity | |
| Substrates | Human IgG1, Human IgG2, Human IgG4, Monkey IgG, Rabbit IgG, Rat IgG, Sheep IgG |
| Reaction Conditions | 30 minute reaction at 37°C according to protocol specifications |
| Digestion Buffers | PBS (pH 6.0 – 8.0), TBS (pH 7.0 – 8.0), MES (pH 5.5 – 6.5), HEPES (pH 7.0 – 8.0), Ammonuim Bicarbonate (pH 6.0 – 7.0), Sodium Acetate (pH 6.0) |
| Buffer Compatibility | |
| Inhibitors | |
| Unit Definition | |
| Application |
Yes, for human IgG1 molecules both enzymes can be used in combination to generate a specific hinge peptide. The incubation time is significantly longer for FabALACTICA and it is recommended to first run the FabALACTICA digest and then add FabRICATOR for the last 30 min.
We have no stability data for storage at -20°C or -70°C. However, we have customer reporting that they successfully stored reconstituted FabRICATOR at -20°C or -70°C for a couple of months. Genovis cannot guarantee the activity of the enzyme, but these storage conditions might be OK depending on the intended application.
Yes, FabRICATOR should be able to digest a Fc fusion protein as long as you have not fused the protein too close to the cleavage site. FabRICATOR digests human IgG just below the hinge (…CPAPELLG / GPSVF…), leaving the hinge on the fusion-part.
We have tested concentrations as low 0.025 mg/ml without any measurable effect on digestion efficiency. However, low concentration samples require a longer injection time and consequently lead to a broader elution peak from the FabRICATOR HPLC column.
We can only guarantee optimal digestion for one-time use. We do not have a cleaning or regeneration protocol to provide. However, depending on the antibody and the following application the column can be reused. We do not recommend using with different antibodies due to the risk for contamination of carry-over from previous sample. If column reuse is desired store the column in 10-20% ethanol at +4-8°C.
It is possible to elute the Fc fragments from the CaptureSelect column using a low pH buffer, for example a 0.1M Glycine buffer pH=3.0. The pH must immediately after elution be adjusted to neutral pH by adding 0.1x elution volume of 1M Tris pH=8.0.
It is possible to use FabRICATOR with low concentrations of IgG. Low concentrations of IgG will lead to decreased reaction rate, so for concentrations below 0.5mg/mL it is therefore recommended to increase the amount of added enzyme and/or increase the incubation time. There is no risk of over-digestion and the incubation time can be prolonged to O/N if necessary.
Yes, PNGaseF and FabRICATOR can be used in a one-pot reaction as long as the reaction conditions follow the specifications for the FabRICATOR enzyme. It is important to have native reaction conditions for FabRICATOR to remain active.
FabRICATOR Fab2 Kit digests rabbit IgG but to capture the Fc fragments in the affinity step you need another resin than the CaptureSelect™ Fc normally included in the kit. Please contact the Genovis team if you are interested in processing rabbit IgG and we will provide columns with resin compatible with rabbit Fc in the FabRICATOR Fab2 Kit.
Yes, it is possible to digest the antibody in the first dimension and then separate the subunits in the second dimension. Please see the application note for detailed instructions.
FabRICATOR MagIC is suitable for using in automated systems that can handle magnetic beads. On the applications page you can read about how it’s used in a KingFisher™ workflow.
Genovis has chosen CaptureSelect in the FabRICATOR Fab2 Kit for removal of Fc fragments. CaptureSelect has a very high specific affinity for the Fc. Both protein A and MabSelect Sure (GE) may have affinity for the Fab which may result in a lower recovery of the generated F(ab’)2 fragments and the degree of affinity is antibody dependent. We have many customer reports on this subject, and they usually come back to us for the CaptureSelect columns for the above reason.
No. According to the following reference, FabRICATOR does not digest IgM. Pavel-Rammingen et al., 2002. IdeS, a novel streptococcal cysteine proteinase with unique specificity for immunoglobulin G.
FabRICATOR is a cysteine protease. It should not result in any other modifications than the digestion of the peptide bond. Digestion will be between the two Glycines (…CPAPELLG / GPSVF…) and the C-terminus will regain the carboxyl group – that is addition of one OH-group and the N-terminal amino group will be regained (addition of one H).
In summary, R1-CO-NH-R2 + H2O –> R1-COOH + NH2-R2.
The FabRICATOR HPLC can run >400 samples of 10 ug of IgG.
If we assume that the antibody concentration in serum is 15 mg/ml you would have to add 10-15 000 units to a sample of 1 ml serum. In 50 µl serum you would have to add 500 – 750 units of FabRICATOR.
FabRICATOR is a very specific enzyme and small changes in the sequence in or around the digestion site (…CPAPELLG / GPSVF…) may reduce or completely impair the ability to digest the IgG. It is very difficult to predict the outcome for each specific modification. It might work, but we cannot guarantee it unfortunately, the only way of knowing is to perform a digestion test. Some suggestions that are worth testing if you experience incomplete digestion: Increase the incubation time, increase the amount of added enzyme, use a PBS with greatly reduced salt concentration (5-10 mM instead of 140 mM) and pH 6.5 instead of 7.4.
We have tested 4-6 M GuHCl which the enzyme does not withstand without significant decrease of activity. SDS have not been evaluated but 0.1% RapiGest from waters have negative influence on activity. Taken together the enzyme does not well tolerate denaturing agents although we have not tested this in more detailed studies.
Yes. FabRICATOR is compatible with EDTA. Make sure your pH is within 6-8.
FabRICATOR HPLC is an HPLC column with the FabRICATOR (IdeS) protease immobilized on a HPLC compatible matrix for automated antibody subunit generation.
The FabRICATOR MagIC magnetic beads with immobilized FabRICATOR (IdeS) enzyme.
FabRICATOR® cleave the IgG molecule in one specific site in the lower hinge region of the anitbody leaving a F(ab’)2 fragment and a Fc-fragment.
Human IgG1: ..CPAPELLG / GPSVF..
Human IgG2: ..CPAPPVA / GPSVF..
Human IgG3: ..CPAPELLG / GPSVF..
Human IgG4: ..CPAPEFLG / GPSVF..
We have tested PBS and 150 mM ammonium acetate, pH7 with good results. More buffers were found to be compatible with FabRICATOR digestion in solution (more info) and should be suitable for FabRICATOR HPLC as well. However, the ionic strength of the buffer influences retention of the antibody fragments on the FabRICATOR HPLC column and a minimum of 100-150 mM salt is necessary for IgG1 subunits to elute as a single, narrow peak. Other IgG subclasses or fusion proteins might need some optimization of buffer composition.
The protocol for FabRICATOR MagIC is based on using standard PBS pH 7.4 as digestion buffer. FabRICATOR in solution is compatible with most commonly used buffers at pH=6-8 and the same buffers should work for FabRICATOR MagIC, but the incubation time might need to be optimized.
