How the Structure of Antibody was Deduced

It produced two identical fragments (each with a molecular weight of 45,000), called Fab fragments and one fragment called Fc fragment. “Gerald Edelman – Biography” (Accessed March 15, 2010)

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Edelman dissociated the molecule by reducing the interchain disulfide bonds. This proved that Fab consists of a heavy and light chain portion while Fc fragment contains only portions of heavy chain. Porter subjected IgG to brief digestion with the enzyme papain and separated the fragments. degree in 1954. The two shared the Nobel Prize in Medicine and Physiology in 1972. “Rodney Porter – Biography” (Accessed March 15, 2010)

The tetra-peptide structure of antibody moleculeThe antibody is an important functional end product of the humoral branch of the adaptive immune system. The remaining puzzle was to determine how the enzyme digestion products Fab, F(ab)2 and Fc were related to the heavy chain and light chain reduction products.

How the Final Pieces of the Puzzle Fell in Place

Porter finally answered the question by using antisera from goat that had been immunized with either the Fab fragments or the Fc fragments of rabbit IgG. It forms a roughly Y shaped structure, where the arms make up what is known as the Fab (fragment, antigen-binding) region and the stem makes up the Fc (fragment, crystallizable) region.

Rodney Porter

Our knowledge of basic antibody structure comes from a variety of experimental observations. He obtained two fractions, one with a MW of 25,000 (light chain) and one with a MW of 50,000 (heavy chain).. Later he became a Professor of the Rockefeller University.

Experiments of Porter and Edelman

Edelmans and Porters experimental approaches were quite different. 2000. In 1949, he joined the scientific staff of the National Institute of Medical Research and was there until 1960 when he joined St. Early experiments by Tiselius and Kabat had proved the presence of an entity in the serum (gamma globulin fraction) which bound with the antigen.

Basic Structure of Immunoglobulin

An antibody molecule is made up of two heavy chains (each with MW 50,000) and two light chains (each with MW 25,000). This treatment cleaves only the most susceptible bonds. Freeman and Co., NY, USA.

Another scientist, Alfred Nisonoff, had a similar approach to Porter, only he used a different enzyme – pepsin. Marys Hospital Medical School, London University as the first Pfizer Professor for Immunology.

Gerald Edelman

Gerald Edelman was born in 1929 in New York, USA. After serving as a Captain in the US Army, he joined the Rockefeller Institute from where he received his Ph.D degree in 1960. He subjected the IgG molecule to mercaptoethanol treatment which irreversibly cleaves the disulfide bonds. Kuby Immunology, 4th ed. H. J. Rodney Porter was born in Lancashire, England in 1917. A. He found that the antibody to the Fab fragment could react with both the H and the L chains, whereas antibody to the Fc fragment reacted only with the H chain. W. He remained at the Institute and eventually became Associate Dean of graduate studies, a position from which he retired in 1966. He did his B.Sc (Hons) in Biochemistry in 1939 at the University of Liverpool and did his Ph.D under the supervision of the great Frederick Sanger in 1948. Both first separated the gamma-globulin fraction of serum into high-and low molecular weight fractions. The heavy chains are attached to each other, whereas the light chains are bound to heavy chains, by means of covalent bonds and many non-covalent linkages. Goldsby, T. Kindt, and B. They both studied the low molecular weight fraction, which contained a 150,000 MW gamma-globulin designated as immunoglobulin G (IgG). Pepsin digestion of IgG yielded a single 100,000 MW fragment composed of two Fab-like fragments and designated F(ab)2. A. Osborne. In the 1950s and 1960s, experiments by Rodney Porter and by Gerald Edelman elucidated the basic structure of the immunoglobulin molecule. He received his B.S. degree, magna cum laude, in 1950. R. It is produced by plasma cells (terminally-differentiated B cells) after being activated by helper T cells. These antibodies are capable of binding to the offending foreign entity (bacterium or virus) and help other mechanisms to remove or destroy them. He then attended the medical school of the University of Pennsylvania from where he received his M.D

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