A Structurally Distinct Human Mycoplasma Protein that Generically Blocks Antigen-Antibody Union

• DOI: 10.1126/science.1246135
• Publication Date: 2014-02-06T19:20:12Z
• Authors: Rajesh K. Grover; Xueyong Zhu; Travis Nieusma; Teresa Jones; Isabel Boero; Amanda S. MacLeod; Adam Mark; Sherry Niessen; Helen J. Kim; Leopold Kong; Nacyra Assad-Garcia; Keehwan Kwon; Marta Chesi; Vaughn V. Smider; Daniel R. Salomon; Diane F. Jelinek; Robert A. Kyle; Richard B. Pyles; John I. Glass; Andrew B. Ward; Ian A. Wilson; Richard A. Lerner
• Keywords: Lymphokines; 0303 health sciences; Immunoglobulin Variable Region; Membrane Proteins; Crystallography, X-Ray; Recombinant Proteins; Protein Structure, Tertiary; 3. Good health; Antigen-Antibody Reactions; Immunoglobulin kappa-Chains; 03 medical and health sciences; Mycoplasma; Bacterial Proteins; Immunoglobulin lambda-Chains; Immunoglobulin G; Humans; Antigens

Easy M

Our immune systems can produce a vastly diverse repertoire of antibody molecules that each recognize and bind to a specific foreign antigen via a hypervariable region. However, there are a few bacterial antigens—such as Protein A, Protein G, and Protein L—that instead bind to the antibody's conserved regions and can bind to a large number of different antibodies. These high-affinity broad-spectrum antibody-binding properties have been widely exploited both in the laboratory and in industry for purifying, immobilizing, and detecting antibodies.

Grover et al.

(p. 656 ) have now identified Protein M found on the surface of human mycoplasma, which displays even broader antibody-binding specificity. The crystal structure of Protein M revealed how Protein-M binding blocks the antibody's antigen binding site. This mechanism may be exploited by mycoplasma to escape the humoral immune response.