Editing Gerald Edelman (section)

==Nobel Prize==
While in Paris serving in the Army, Edelman read a book that sparked his interest in [[antibody|antibodies]].<ref name="Frontiers">{{cite web |url=https://www.pbs.org/saf/1101/features/edelman.htm |title=Frontiers Profile: Gerry Edelman |website=[[PBS]] |access-date=September 27, 2007 |date=November 21, 2000 |archive-date=September 28, 2020 |archive-url=https://web.archive.org/web/20200928124744/https://www.pbs.org/saf/1101/features/edelman.htm/ |url-status=dead }}</ref> He decided that, since the book said so little about antibodies, he would investigate them further upon returning to the United States, which led him to study [[physical chemistry]] for his 1960 Ph.D.<ref name="Frontiers" /> Research by Edelman and his colleagues and [[Rodney Robert Porter]] in the early 1960s produced fundamental breakthroughs in the understanding of the antibody's chemical structure, opening a door for further study.<ref name="Nobel Press Release">{{cite press release |title=The Nobel Prize in Physiology or Medicine 1972 |publisher=Karolinksa Institutet |date=October 1972 |url=http://nobelprize.org/nobel_prizes/medicine/laureates/1972/press.html |access-date=September 27, 2007 |quote=Their discoveries represent clearly a break-through that immediately incited a fervent research activity the whole world over ...}}</ref> For this work, Edelman and Porter shared the [[Nobel Prize in Physiology or Medicine]] in 1972.<ref name="Nobel Prize" />

In its Nobel Prize press release in 1972, the [[Karolinska Institutet]] lauded Edelman and Porter's work as a major breakthrough:

{{blockquote|The impact of Edelman's and Porter's discoveries is explained by the fact that they provided a clear picture of the structure and mode of action of a group of biologically particularly important substances. By this they laid a firm foundation for truly rational research, something that was previously largely lacking in immunology. Their discoveries represent clearly a break-through that immediately incited a fervent research activity the whole world over, in all fields of immunological science, yielding results of practical value for clinical diagnostics and therapy.<ref>[http://nobelprize.org/nobel_prizes/medicine/laureates/1972/press.html Karolinska Institutet press release, October 1972]</ref>}}

===Disulfide bonds===
[[File:Anticorps.png|thumb|right|272px|Diagram illustrating the [[disulfide bond]]s (red) that link the [[Immunoglobulin light chain|light]] (green) and [[Immunoglobulin heavy chain|heavy]] (blue) protein subunits of [[Immunoglobulin G]] (IgG) molecules. This diagram also illustrates the relative positions of the variable (V) and constant (C) domains of an IgG molecule. The heavy and light chain variable regions come together to form antigen binding sites at the end of the two symmetrical arms of the antibody.]]
Edelman's early research on the structure of antibody proteins revealed that [[Disulfide bond#Occurrence in proteins|disulfide bonds]] link together the protein subunits.<ref name="Edelman1961"/> The protein subunits of antibodies are of two types, the larger heavy chains and the smaller light chains. Two light and two heavy chains are linked together by disulfide bonds to form a functional antibody.

===Molecular models of antibody structure===
Using experimental data from his own research and the work of others, Edelman developed molecular models of antibody proteins.<ref>{{Cite journal
| pmid = 14173001
| year = 1964
| last1 = Edelman | first1 = G.
| last2 = Gally | first2 = J.
| title = A Model for the 7S Antibody Molecule
| volume = 51
| issue = 5
| pages = 846–853
| pmc = 300172
| journal = Proceedings of the National Academy of Sciences of the United States of America
| doi = 10.1073/pnas.51.5.846
|bibcode = 1964PNAS...51..846E | doi-access = free
}}</ref> A key feature of these models included the idea that the [[antigen]] binding domains of antibodies ([[Fragment antigen-binding|Fab]]) include [[amino acid]]s from both the [[Immunoglobulin light chain|light]] and [[Immunoglobulin heavy chain|heavy]] protein subunits. The inter-chain disulfide bonds help bring together the two parts of the antigen binding domain.

===Antibody sequencing===
Edelman and his colleagues used [[Cyanogen bromide#Protein cleavage|cyanogen bromide]] and [[protease]]s to fragment the antibody protein subunits into smaller pieces that could be analyzed for determination of their [[Protein sequencing|amino acid sequence]].<ref>{{Cite journal
| pmid = 5650389
| year = 1968
| last1 = Cummingham | first1 = B.
| last2 = Gottlieb | first2 = P.
| last3 = Konigsberg | first3 = W.
| last4 = Edelman | first4 = G.
| title = The covalent structure of a human gamma G-immunoglobulin. V. Partial amino acid sequence of the light chain
| volume = 7
| issue = 5
| pages = 1983–1994
| journal = Biochemistry
| doi = 10.1021/bi00845a049
}}</ref><ref>{{Cite journal
| pmid = 4177258
| year = 1968
| last1 = Gottlieb | first1 = P. D.
| last2 = Cunningham | first2 = B. A.
| last3 = Waxdal | first3 = M. J.
| last4 = Konigsberg | first4 = W. H.
| last5 = Edelman | first5 = G. M.
| title = Variable regions of heavy and light polypeptide chains of the same gammaG-immunoglobulin molecule
| volume = 61
| issue = 1
| pages = 168–175
| pmc = 285919
| journal = Proceedings of the National Academy of Sciences of the United States of America
| doi = 10.1073/pnas.61.1.168
|bibcode = 1968PNAS...61..168G | doi-access = free
}}</ref> At the time when the first complete antibody sequence was determined (1969)<ref>{{Cite journal
| pmid = 5257969
| year = 1969
| last1 = Edelman | first1 = G. M.
| last2 = Cunningham | first2 = B. A.
| last3 = Gall | first3 = W. E.
| last4 = Gottlieb | first4 = P. D.
| last5 = Rutishauser | first5 = U.
| last6 = Waxdal | first6 = M. J.
| title = The covalent structure of an entire gammaG immunoglobulin molecule
| volume = 63
| issue = 1
| pages = 78–85
| pmc = 534037
| journal = Proceedings of the National Academy of Sciences of the United States of America
| doi = 10.1073/pnas.63.1.78
|bibcode = 1969PNAS...63...78E | doi-access = free
}}</ref> it was the largest complete protein sequence that had ever been determined. The availability of amino acid sequences of antibody proteins allowed recognition of the fact that the body can produce many different antibody proteins with similar antibody constant regions and divergent antibody [[variable region]]s.

===Topobiology===
Topobiology is Edelman's theory which asserts that morphogenesis is driven by differential adhesive interactions among heterogeneous cell populations and it explains how a single cell can give rise to a complex multi-cellular organism. As proposed by Edelman in 1988, topobiology is the process that sculpts and maintains differentiated tissues and is acquired by the energetically favored segregation of cells through heterologous cellular interactions.