Linked Life Data

1369293

Source:http://linkedlifedata.com/resource/pubmed/id/1369293

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
7
pubmed:dateCreated
1991-4-23
pubmed:abstractText
Peptides with affinity for opioid receptors were found in an artificially methyl-esterified peptic digest of human lactoferrin. Three active peptides were purified by two steps of reverse-phase high-performance liquid chromatography. Their structures were Tyr-Leu-Gly-Ser-Gly-Tyr-OCH3, Arg-Tyr-Tyr-Gly-Tyr-OCH2, and Lys-Tyr-Leu-Gly-Pro-Gln-Tyr-OCH3, which respectively correspond to the methyl esters of residues 318-323, 536-540, and 673-679 of human lactoferrin. The IC50 values of these peptides were 15, 10 and 23 microM, respectively, in a radioreceptor assay in the presence of 1 nM [3H]naloxone. In the myenteric plexus preparation of the longitudinal muscle of guinea pig ileum, the individual peptides had no opioid agonist activities, but they antagonized [Met5]enkephalin and morphiceptin when they were at a concentration of 10(-6)-10(-5) M, suggesting that these were the opioid antagonist peptides. These three opioid antagonist peptides were named lactoferroxin A, B and C, after casoxin, the opioid antagonist peptide derived from bovine kappa-casein. Concerning the antagonist activities of lactoferroxins for opioid receptor sub-types, lactoferroxin A showed preference for mu-receptors, while lactoferroxin B and C had somewhat higher degrees of preference for kappa-receptors than for mu-receptors. A study of the structure-activity relationship of the three lactoferroxins and their synthetic analogues showed that these opioid antagonist peptides derived from food protein could be expressed by the general formula XA-Tyr-XB-Tyr-OCH3. An amino acid in position XA may affect the specificity of the antagonist peptide for opioid receptor sub-types.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
B
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0002-1369
pubmed:author
pubmed:issnType
Print
pubmed:volume
54
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1803-10
pubmed:dateRevised
2011-11-17
pubmed:meshHeading
pubmed:year
1990
pubmed:articleTitle
Isolation and characterization of opioid antagonist peptides derived from human lactoferrin.
pubmed:affiliation
Department of Food Science and Technology, Faculty of Agriculture, Kyoto University, Japan.
pubmed:publicationType
Journal Article