Linked Life Data

6313043

Source:http://linkedlifedata.com/resource/pubmed/id/6313043

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
19
pubmed:dateCreated
1983-12-20
pubmed:abstractText
Exorphins, peptides with opioid activity, have previously been isolated from pepsin hydrolysates of alpha-casein [Zioudrou, C., Streaty, R. A., & Klee, W. A. (1979) J. Biol. Chem. 254, 2446-2449]. Analysis of these peptides shows that they correspond to the sequences 90-96, Arg-Tyr-Leu-Gly-Tyr-Leu-Glu, and 90-95, Arg-Tyr-Leu-Gly-Tyr-Leu, of alpha-casein. These peptides, as well as two of their analogues Tyr-Leu-Gly-Tyr-Leu-Glu (91-96) and Tyr-Leu-Gly-Tyr-Leu (91-95), have now been synthesized and characterized. Their opioid activity was examined by three different bioassays: (a) displacement of D-2-alanyl[tyrosyl-3,5-3H]enkephalin-(5-L-methioninamide) and [3H]dihydromorphine from rat brain membranes; (b) naloxone-reversible inhibition of adenylate cyclase in homogenates of neuroblastoma x glioma hybrid cells; (c) naloxone-reversible inhibition of electrically stimulated contractions of the mouse vas deferens. The synthetic peptide of sequence 90-96 was the most potent opioid in all three bioassays and its potency was similar to that of the isolated alpha-casein exorphins. The synthetic peptides were totally resistant to hydrolysis by trypsin and homogenates of rat brain membranes, but were partially inactivated by chymotrypsin and subtilisin. The difference in opioid activity of alpha-casein exorphins may be related to differences in conformational flexibility observed by NMR spectroscopy.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0006-2960
pubmed:author
pubmed:issnType
Print
pubmed:day
13
pubmed:volume
22
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
4567-73
pubmed:dateRevised
2003-11-14
pubmed:meshHeading
pubmed:year
1983
pubmed:articleTitle
Opioid activities and structures of alpha-casein-derived exorphins.
pubmed:publicationType
Journal Article