Linked Life Data

11029593

Source:http://linkedlifedata.com/resource/pubmed/id/11029593

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
21
pubmed:dateCreated
2000-11-22
pubmed:abstractText
Five new low-molecular-mass trypsin inhibitors belonging to the RTI/MTI-2 family were identified from white mustard (Sinapis alba L. ; MTI-2) seed. Purified MTI-2 consisted of a peptide mixture, displaying Ile or Arg at position 43, Trp or kynurenine (Kyn) at position 44, and C-terminal ragged ends. The occurrence of Ile or Arg at position 43 suggested that MTI-2 inhibitors originated from different genes. The presence of 5-oxo-proline (pyroglutamic acid; 5-oxoPro1) and Kyn44 reflected post-translational processing of the serine proteinase inhibitor. MTI-2 showed approximately 70% amino-acid identity with low-molecular-mass trypsin inhibitors isolated from oil rape (Brassica napus var. oleifera; RTI-III) seed and with serine proteinase inhibitors mapped in Arabidopsis thaliana chromosome II (ATTI). Furthermore, MTI-2 was homologous to brazzein, the sweet-tasting protein from Pentadiplandra brazzeana Baillon fruit ( approximately 30% amino-acid identity). Although snake-venom toxins showed a low amino-acid identity (< 20%) with MTI-2, RTI-III, and ATTI, some structurally relevant residues were conserved. The disulfide bridge pattern of MTI-2 (Cys5-Cys27, Cys18-Cys31, Cys42-Cys52, and Cys54-Cys57) corresponded to that of RTI-III and of snake-venom toxins, being different from that of brazzein. Therefore, protein similarity might be attributable to the three-dimensional arrangement rather than to the amino-acid sequence. Values of Ka for MTI-2 binding to bovine beta-trypsin (trypsin) and bovine alpha-chymotrypsin were 6.3 x 109 M-1 and 2.0 x 106 M-1, respectively, at pH 8.0 and 21.0 degrees C. Moreover, values of kon for MTI-2 binding to trypsin and of koff for the dissociation of the serine proteinase:inhibitor complex were 5.6 x 105 M-1.s-1 and 8.9 x 10-5 M-1.s-1, respectively, at pH 8.0 and 21.0 degrees C. Despite the heterogeneity of the purified inhibitor peptide mixture, the inhibition properties of the different MTI-2 inhibitors were indistinguishable.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0014-2956
pubmed:author
pubmed:issnType
Print
pubmed:volume
267
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
6486-92
pubmed:dateRevised
2007-7-23
pubmed:meshHeading
pubmed-meshheading:11029593-Amino Acid Sequence, pubmed-meshheading:11029593-Chromatography, High Pressure Liquid, pubmed-meshheading:11029593-Chymotrypsin, pubmed-meshheading:11029593-Disulfides, pubmed-meshheading:11029593-Endopeptidases, pubmed-meshheading:11029593-Kinetics, pubmed-meshheading:11029593-Molecular Sequence Data, pubmed-meshheading:11029593-Molecular Weight, pubmed-meshheading:11029593-Mustard Plant, pubmed-meshheading:11029593-Peptide Fragments, pubmed-meshheading:11029593-Plant Proteins, pubmed-meshheading:11029593-Plants, Medicinal, pubmed-meshheading:11029593-Seeds, pubmed-meshheading:11029593-Sequence Alignment, pubmed-meshheading:11029593-Sequence Analysis, Protein, pubmed-meshheading:11029593-Spectrometry, Mass, Electrospray Ionization, pubmed-meshheading:11029593-Spectrometry, Mass, Matrix-Assisted Laser..., pubmed-meshheading:11029593-Thermodynamics, pubmed-meshheading:11029593-Thermolysin, pubmed-meshheading:11029593-Trypsin, pubmed-meshheading:11029593-Trypsin Inhibitors
pubmed:year
2000
pubmed:articleTitle
Characterization of five new low-molecular-mass trypsin inhibitors from white mustard (Sinapis alba L.) seed.
pubmed:affiliation
Dipartimento di Chimica, Università di Salerno, Italy.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't