Photoaffinity labeling

Photoaffinity labeling is a chemoproteomics technique used to attach "labels" to the active site of a large molecule, especially a protein. The "label" attaches to the molecule loosely and reversibly, and has an inactive site which can be converted using photolysis into a highly reactive form, which causes the label to bind more permanently to the large molecule via a covalent bond.[http://www.merriam-webster.com/medical/photoaffinity%20labeling Photoaffinity labeling][http://goldbook.iupac.org/P04578.html Photoaffinity labeling], Gold Book The technique was first described in the 1970s.{{Cite journal

| doi = 10.1073/pnas.70.9.2567

| last1 = Ruoho | first1 = A. E.

| last2 = Kiefer | first2 = H.

| last3 = Roeder | first3 = P. E.

| last4 = Singer | first4 = S. J.

| title = The mechanism of photoaffinity labeling

| journal = Proceedings of the National Academy of Sciences of the United States of America

| volume = 70

| issue = 9

| pages = 2567–2571

| year = 1973

| pmid = 4517671

| pmc = 427057

| bibcode = 1973PNAS...70.2567R | doi-access = free }} Molecules that have been used as labels in this process are often analogs of complex molecules, in which certain functional groups are replaced with a photoreactive group, such as an azide, a diazirine or a benzophenone.{{Cite journal

| last1 = Bush | first1 = J. T.

| last2 = Walport | first2 = L. J.

| last3 = McGouran | first3 = J. F.

| last4 = Leung | first4 = I. K. H.

| last5 = Berridge | first5 = G.

| title = The Ugi four-component reaction enables expedient synthesis and comparison of photoaffinity probes

| doi = 10.1039/C3SC51708J

| journal = Chemical Science

| volume = 4

| issue = 12

| pages = 4115–4120

| year = 2013

| pmid =

| pmc =

| doi-access = free}}{{Cite journal

| last1 = Panov | first1 = M. S.

| last2 = Voskresenska | first2 = V. D.

| last3 = Ryazantsev | first3 = M. N.

| last4 = Tarnovsky | first4 = A. N.

| last5 = Wilson | first5 = R. M.

| title = 5-Azido-2-aminopyridine, a New Nitrene/Nitrenium Ion Photoaffinity Labeling Agent That Exhibits Reversible Intersystem Crossing between Singlet and Triplet Nitrenes

| doi = 10.1021/ja405637b

| journal = Journal of the American Chemical Society

| volume = 135

| issue = 51

| pages = 19167–19179

| year = 2013

| pmid = 24219134

| pmc =

| bibcode = 2013JAChS.13519167P

| url = https://scholarworks.bgsu.edu/chem_pub/182

}}{{Cite journal

| last1 = Akiyama | first1 = S.

| last2 = Cornwell | first2 = M. M.

| last3 = Kuwano | first3 = M.

| last4 = Pastan | first4 = I.

| last5 = Gottesman | first5 = M. M.

| title = Most drugs that reverse multidrug resistance also inhibit photoaffinity labeling of P-glycoprotein by a vinblastine analog

| journal = Molecular Pharmacology

| volume = 33

| issue = 2

| pages = 144–147

| year = 1988

| pmid = 2893251

}}