Lyophilized solid. Native protein G from Streptococcus species. Provides a versatile and economical means for isolating, detecting, and purifying antibodies. It is especailly useful in immunohistochemical studies because, unlike secondary antibodies, it does not bind to cell Fc receptors and, therefore, will not give high background reactions. Strongly reactive with human IgG₁, IgG₂, IgG₃, and IgG₄; mouse IgG₁, IgG_2a, IgG_2b, IgG₃; rat IgG_2a; horse, bovine, porcine, and rabbit IgG. Weakly reactive with rat IgG₁, IgG_2b, IgG_2c; sheep, goat, chicken, hamster, and guinea pig. Does not react with IgM, IgD, IgE, or IgA. Binding capacity: ~2.4 mg goat IgG/ml of 10% solution.

Ref.: Fahnestock, S. 1987. Trends Biotechnol. 5, 790.