Recombinant Protein A

Recombinant Protein A

Catalog Number: AX-AP1100

Size: 5 mg

Source: Escherichia coli

Description: Protein A is a cell wall component produced by several strains of Staphylococcus aureus that consists of a single polypeptide chain and contains little or no carbohydrate. Recombinant Protein A is produced in E.Coli and functions essentially the same as native Protein A. It consists of 5 IgG-binding domains E-D-A-B-C aligned in series. It migrates with an apparent molecular mass of 45kDa in SDS-PAGE.

Purity: >95% by SDS-PAGE analyses.

Specificity: The interaction between Protein A and IgG is not equivalent for all species. Even within a species, Protein A interacts with some subclasses of IgG and not others. For instance, human IgG1, IgG2 and IgG4 bind strongly, while IgG3 does not bind. There are also many instances in which monoclonal antibodies do not bind to Protein A, especially the majority of rat immunoglobulins and mouse IgG1.

Applications: The Protein A molecule contains four high-affinity (Ka =108/mole) binding sites capable of interacting with the Fc region from IgG of several species including human and rabbit Optimal binding occurs a pH 8.2, although binding is also good at neutral or physiological conditions (pH 7.0-7.6).

Appearance: Sterile Filtered White lyophilized (freeze-dried) powder.

Formulation: Lyophilized with no additive.

Endotoxin: Less than 0.1EU/μg of Protein A as determined by LAL method.

Reconstitution: Dissolve in distilled water or saline.

Storage: 2 years at -20°C. After reconstitution, aliquot and store at -20°C. Avoid repeated freeze/thaw cycles.

Usage: This material is for research, laboratory or further evaluation purposes.

IgG Binging to Protein A, G and L:

Strong binding ＋＋, medium interaction ＋, weak or no interaction －.