Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
7
pubmed:dateCreated
1999-3-11
pubmed:abstractText
Phenoloxidase inhibitor (POI), found in the hemolymph of housefly pupae, is a novel dopa-containing and cystine-rich peptide that competitively inhibits phenoloxidase with a Ki in the nanomolar range. [Tyr32]POI is a potential precursor molecule also found in the hemolymph that may be posttranslationally oxidized to the dopa-containing peptide after creation of a rigid structure. By employing both a solid-phase peptide synthesis system based on a 9-fluorenylmethoxycarbonyl strategy and a specific air oxidation technique to ensure correct folding, we have been able to synthesize [Tyr32]POI. The synthetic [Tyr32]POI was confirmed to be identical to the native [Tyr32]POI by coelution high-performance liquid chromatography analysis and by enzymatic analysis using the phenoloxidase inhibition assay. To determine the disulfide pairings within the peptides, a series of enzyme hydrolyses and partial reduction/alkylation steps were performed. Three cystine pairs (Cys11-Cys25, Cys18-Cys29, and Cys24-Cys36) were determined by identification of the resulting peptides. The disulfide pairings of the two adjacent Cys residues (Cys11-Cys25 and Cys24-Cys36) were unambiguously assigned by comparing the derived fragments with the two possible isomers synthesized through a novel disulfide-linking technique. The arrangement of the disulfide bridges in POI was found to be topologically identical to those found for several peptides within the inhibitor cystine knot structural family. Although these peptides share a low primary sequence homology and display a diversity of biological functions, they nonetheless share similarities in their cystine motifs and tertiary structure. The tertiary structure model of POI, which was derived through molecular dynamics and energy minimization studies using restraints with determined disulfide connectivities, suggests that POI is a new class member of the inhibitor cystine-knot structural family.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
http://linkedlifedata.com/resource/pubmed/chemical/Cysteine, http://linkedlifedata.com/resource/pubmed/chemical/Cystine, http://linkedlifedata.com/resource/pubmed/chemical/Disulfides, http://linkedlifedata.com/resource/pubmed/chemical/Enzyme Inhibitors, http://linkedlifedata.com/resource/pubmed/chemical/Insect Proteins, http://linkedlifedata.com/resource/pubmed/chemical/Mollusk Venoms, http://linkedlifedata.com/resource/pubmed/chemical/Monophenol Monooxygenase, http://linkedlifedata.com/resource/pubmed/chemical/Peptide Fragments, http://linkedlifedata.com/resource/pubmed/chemical/Peptides, http://linkedlifedata.com/resource/pubmed/chemical/Phosphines, http://linkedlifedata.com/resource/pubmed/chemical/Serine Endopeptidases, http://linkedlifedata.com/resource/pubmed/chemical/Spider Venoms, http://linkedlifedata.com/resource/pubmed/chemical/Tyrosine, http://linkedlifedata.com/resource/pubmed/chemical/Water, http://linkedlifedata.com/resource/pubmed/chemical/lysyl endopeptidase, http://linkedlifedata.com/resource/pubmed/chemical/phenol oxidase inhibitor, housefly, http://linkedlifedata.com/resource/pubmed/chemical/phosphine
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0006-2960
pubmed:author
pubmed:issnType
Print
pubmed:day
16
pubmed:volume
38
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2179-88
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed-meshheading:10026302-Amino Acid Sequence, pubmed-meshheading:10026302-Animals, pubmed-meshheading:10026302-Computer Simulation, pubmed-meshheading:10026302-Cysteine, pubmed-meshheading:10026302-Cystine, pubmed-meshheading:10026302-Disulfides, pubmed-meshheading:10026302-Enzyme Inhibitors, pubmed-meshheading:10026302-Houseflies, pubmed-meshheading:10026302-Hydrolysis, pubmed-meshheading:10026302-Insect Proteins, pubmed-meshheading:10026302-Models, Molecular, pubmed-meshheading:10026302-Molecular Sequence Data, pubmed-meshheading:10026302-Mollusk Venoms, pubmed-meshheading:10026302-Monophenol Monooxygenase, pubmed-meshheading:10026302-Peptide Fragments, pubmed-meshheading:10026302-Peptides, pubmed-meshheading:10026302-Phosphines, pubmed-meshheading:10026302-Serine Endopeptidases, pubmed-meshheading:10026302-Solubility, pubmed-meshheading:10026302-Spider Venoms, pubmed-meshheading:10026302-Tyrosine, pubmed-meshheading:10026302-Water
pubmed:year
1999
pubmed:articleTitle
A novel endogenous inhibitor of phenoloxidase from Musca domestica has a cystine motif commonly found in snail and spider toxins.
pubmed:affiliation
Department of Applied Biological Sciences, Saga University, Japan.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't