N-(3-(p-azido-m-[125I]iodophenyl)propionyl)-succinimide--a heterobifunctional reagent for the synthesis of radioactive photoaffinity ligands: synthesis of a carrier-free 125I-labeled cardiac glycoside photoaffinity label.
A new heterobifunctional reagent, N-(3-(p-azido-m-iodophenyl)propionyl)-succinimide (AIPPS), was synthesized and chemically characterized. The radiochemical form of the reagent, [125I]AIPPS, should be of general use as a photoactive reagent for the derivatization of free amino groups on a large variety of biologically active compounds, including many hormones. Amino-containing ligands can be derivatized with [125I]AIPPS in a method which is similar to that used for the 125I-labeled Bolton-Hunter reagent (N-(3-(p-hydroxyphenyl)propionyl)-succinimide). The added advantage with [125I]AIPPS, however, is that the ligand derivative is made both photoactive and radioactive in a single step. As an example of how this reagent can be used, we have prepared carrier-free [125I]AIPPS and reacted it with the amino-containing cardiac glycoside, 4-amino-4,6-dideoxyglucosyl digitoxigenin (GluD). The radioiodinated cardiac glycoside, [125I]AIPP-GluD, was purified by thin-layer chromatography and was carrier-free with a specific radioactivity of 2175 Ci/mmol. [125I]AIPP-GluD was an effective photoaffinity label for Na,K-ATPase as shown by specific photoaffinity labeling of purified canine kidney enzyme and human erythrocyte enzyme.
Lowndes
J M
JM
Department of Physiological Chemistry, University of Wisconsin, Madison 53706.
Hokin-Neaverson
M
M
Ruoho
A E
AE
D000345:Affinity Labels / Q000138:chemical synthesis*; D000818:Animals; D001386:Azides / Q000138:chemical synthesis*; D002301:Cardiac Glycosides / Q000138:chemical synthesis*; D003432:Cross-Linking Reagents / Q000138:chemical synthesis*; D004073:Digitoxigenin / Q000031:analogs & derivatives* / Q000138:chemical synthesis; D004285:Dogs; D004912:Erythrocytes / Q000201:enzymology; D006801:Humans; D007457:Iodine Radioisotopes; D007553:Isotope Labeling; D007668:Kidney / Q000201:enzymology; D010777:Photochemistry; D000254:Sodium-Potassium-Exchanging ATPase / Q000032:analysis; D013388:Succinimides / Q000138:chemical synthesis*
D000345:Affinity Labels; D001386:Azides; D002301:Cardiac Glycosides; D003432:Cross-Linking Reagents; D007457:Iodine Radioisotopes; D013388:Succinimides; C055612:N-(3-(4-azido-3-iodophenyl)propionyl)succinimide; C055650:3-(4-azido-3-iodophenyl)propionamide-4-(4,6-dideoxyglucosyl)digitoxigenin; D004073:Digitoxigenin; D000254:Sodium-Potassium-Exchanging ATPase