IgG-binding A protein (His)

Protein A protein (His) is the recombinant Staphylococcus aureus-derived Protein A, expressed by E. coli , with C-6*His labeled tag.

Protein A/G plays a role in inhibiting both the host innate and adaptive immune responses. It contains five immunoglobulin-binding domains that capture the Fc region and Fab region of immunoglobulins. By inhibiting the Ig Fc region, it protects Staphylococcus aureus from phagocytic killing. Additionally, it suppresses the host B-cell response by reducing the proliferation of antibody-secreting cells entering the bone marrow, thereby diminishing long-term antibody production. Protein A/G also inhibits osteogenesis by preventing osteoblast proliferation and the expression of alkaline phosphatase, type I collagen, osteopontin, and osteocalcin. Furthermore, it acts as a pro-inflammatory factor in the lungs by binding to and activating tumor necrosis factor alpha receptor 1/TNFRSF1A (By similarity).

Measured by its binding ability in a functional ELISA. Immobilized Protein A at 2 μg/mL (100μL/well) can bind Biotinylated IgG1. The ED₅₀ for this effect is 0.1293 μg/mL.

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  Measured by its binding ability in a functional ELISA. Immobilized Protein A at 2 μg/mL (100 μL/well) can bind Biotinylated IgG1. The ED₅₀ for this effect is 0.1293 μg/mL.

Staphylococcus aureus

E. coli

C-6*His

P02976 (N35-D330)

3919448

Partial

NAAQHDEAQQNAFYQVLNMPNLNADQRNGFIQSLKDDPSQSANVLGEAQKLNDSQAPKADAQQNNFNKDQQSAFYEILNMPNLNEAQRNGFIQSLKDDPSQSTNVLGEAKKLNESQAPKADNNFNKEQQNAFYEILNMPNLNEEQRNGFIQSLKDDPSQSANLLSEAKKLNESQAPKADNKFNKEQQNAFYEILHLPNLNEEQRNGFIQSLKDDPSQSANLLAEAKKLNDAQAPKADNKFNKEQQNAFYEILHLPNLTEEQRNGFIQSLKDDPSVSKEILAEAKKLNDAQAPKEED

Approximately 32-35 kDa, based on SDS-PAGE under reducing conditions, due to the glycosylation.

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  ≥ 95%, as determined by reducing SDS-PAGE.

Lyophilized powder.

Lyophilized from a 0.22 μm filtered solution of PBS, pH 7.4, 5% trehalose, 5% mannitol and 0.01% Tween 80.

<1 EU/μg, determined by LAL method.

It is not recommended to reconstitute to a concentration less than 100 μg/mL in ddH₂O.

Stored at -20°C for 2 years from date of receipt. After reconstitution, it is stable at 4°C for 1 week or -20°C for longer (with carrier protein). It is recommended to freeze aliquots at -20°C or -80°C for extended storage.

Room temperature in continental US; may vary elsewhere.