{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,13]],"date-time":"2026-10-13T14:52:53Z","timestamp":1791903173830,"version":"4.3.4"},"reference-count":0,"publisher":"National Academy of Sciences","issue":"13","content-domain":{"domain":["www.pnas.org"],"crossmark-restriction":true},"short-container-title":["Proc. Natl. Acad. Sci. U.S.A."],"published-print":{"date-parts":[[1989,7]]},"abstract":"<jats:p>Deltorphins are endogenous linear heptapeptides, isolated from skin extracts of frogs belonging to the genus Phyllomedusa, that have a higher affinity and selectivity for delta opioid binding sites than any other natural compound known. Two deltorphins with the sequence Tyr-Ala-Phe-Asp(or Glu)-Val-Val-Gly-NH2 have been isolated from skin extracts of Phyllomedusa bicolor. The alanine in position 2 is in the D configuration. These peptides, [D-Ala2]deltorphins I and II, show an even higher affinity for delta receptors than the previously characterized deltorphin, which contains D-methionine as the second amino acid. These peptides show some similarity to another constituent of Phyllomedusa skin, dermorphin, which is highly selective for mu-opioid receptors. These peptides all have the N-terminal sequence Tyr-D-Xaa-Phe, where D-Xaa is either D-alanine or D-methionine. While this structure seems to be capable of activating both mu and delta opioid receptors, differences in the C-terminal regions of these peptides are probably responsible for the observed high receptor selectivity of dermorphin and deltorphin.<\/jats:p>","DOI":"10.1073\/pnas.86.13.5188","type":"journal-article","created":{"date-parts":[[2006,5,31]],"date-time":"2006-05-31T06:58:01Z","timestamp":1149058681000},"page":"5188-5192","update-policy":"https:\/\/doi.org\/10.1073\/pnas.cm10313","source":"Crossref","is-referenced-by-count":359,"title":["Deltorphins: a family of naturally occurring peptides with high affinity and selectivity for delta opioid binding sites."],"prefix":"10.1073","volume":"86","author":[{"given":"V","family":"Erspamer","sequence":"first","affiliation":[{"name":"Department of Biochemical Sciences, University La Sapienza, Rome, Italy."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"P","family":"Melchiorri","sequence":"additional","affiliation":[{"name":"Department of Biochemical Sciences, University La Sapienza, Rome, Italy."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"G","family":"Falconieri-Erspamer","sequence":"additional","affiliation":[{"name":"Department of Biochemical Sciences, University La Sapienza, Rome, Italy."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"L","family":"Negri","sequence":"additional","affiliation":[{"name":"Department of Biochemical Sciences, University La Sapienza, Rome, Italy."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"R","family":"Corsi","sequence":"additional","affiliation":[{"name":"Department of Biochemical Sciences, University La Sapienza, Rome, Italy."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"C","family":"Severini","sequence":"additional","affiliation":[{"name":"Department of Biochemical Sciences, University La Sapienza, Rome, Italy."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"D","family":"Barra","sequence":"additional","affiliation":[{"name":"Department of Biochemical Sciences, University La Sapienza, Rome, Italy."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"M","family":"Simmaco","sequence":"additional","affiliation":[{"name":"Department of Biochemical Sciences, University La Sapienza, Rome, Italy."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"G","family":"Kreil","sequence":"additional","affiliation":[{"name":"Department of Biochemical Sciences, University La Sapienza, Rome, Italy."}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"341","published-online":{"date-parts":[[1989,7]]},"container-title":["Proceedings of the National Academy of Sciences"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/pnas.org\/doi\/pdf\/10.1073\/pnas.86.13.5188","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2022,4,13]],"date-time":"2022-04-13T12:56:11Z","timestamp":1649854571000},"score":1,"resource":{"primary":{"URL":"https:\/\/pnas.org\/doi\/full\/10.1073\/pnas.86.13.5188"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[1989,7]]},"references-count":0,"journal-issue":{"issue":"13","published-print":{"date-parts":[[1989,7]]}},"alternative-id":["10.1073\/pnas.86.13.5188"],"URL":"https:\/\/doi.org\/10.1073\/pnas.86.13.5188","relation":{},"ISSN":["0027-8424","1091-6490"],"issn-type":[{"value":"0027-8424","type":"print"},{"value":"1091-6490","type":"electronic"}],"subject":[],"published":{"date-parts":[[1989,7]]},"assertion":[{"value":"1989-07-01","order":2,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}]}}