Linked Life Data

15448155

Source:http://linkedlifedata.com/resource/pubmed/id/15448155

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
50
pubmed:dateCreated
2004-12-6
pubmed:abstractText
DPP-IV is a prolyl dipeptidase, cleaving the peptide bond after the penultimate proline residue. It is an important drug target for the treatment of type II diabetes. DPP-IV is active as a dimer, and monomeric DPP-IV has been speculated to be inactive. In this study, we have identified the C-terminal loop of DPP-IV, highly conserved among prolyl dipeptidases, as essential for dimer formation and optimal catalysis. The conserved residue His750 on the loop contributes significantly for dimer stability. We have determined the quaternary structures of the wild type, H750A, and H750E mutant enzymes by several independent methods including chemical cross-linking, gel electrophoresis, size exclusion chromatography, and analytical ultracentrifugation. Wild-type DPP-IV exists as dimers both in the intact cell and in vitro after purification from human semen or insect cells. The H750A mutation results in a mixture of DPP-IV dimer and monomer. H750A dimer has the same kinetic constants as those of the wild type, whereas the H750A monomer has a 60-fold decrease in kcat. Replacement of His750 with a negatively charged Glu (H750E) results in nearly exclusive monomers with a 300-fold decrease in catalytic activity. Interestingly, there is no dynamic equilibrium between the dimer and the monomer for all forms of DPP-IVs studied here. This is the first study of the function of the C-terminal loop as well as monomeric mutant DPP-IVs with respect to their enzymatic activities. The study has important implications for the discovery of drugs targeted to the dimer interface.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
10
pubmed:volume
279
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
52338-45
pubmed:dateRevised
2010-11-18
pubmed:meshHeading
pubmed-meshheading:15448155-Adenosine Deaminase, pubmed-meshheading:15448155-Adenosine Deaminase Inhibitors, pubmed-meshheading:15448155-Amino Acid Sequence, pubmed-meshheading:15448155-Animals, pubmed-meshheading:15448155-Baculoviridae, pubmed-meshheading:15448155-Base Sequence, pubmed-meshheading:15448155-Cell Line, pubmed-meshheading:15448155-Conserved Sequence, pubmed-meshheading:15448155-DNA, Complementary, pubmed-meshheading:15448155-Dimerization, pubmed-meshheading:15448155-Dipeptidyl Peptidase 4, pubmed-meshheading:15448155-Glycoproteins, pubmed-meshheading:15448155-Humans, pubmed-meshheading:15448155-Kinetics, pubmed-meshheading:15448155-Male, pubmed-meshheading:15448155-Models, Molecular, pubmed-meshheading:15448155-Molecular Sequence Data, pubmed-meshheading:15448155-Mutagenesis, Site-Directed, pubmed-meshheading:15448155-Protein Structure, Quaternary, pubmed-meshheading:15448155-Recombinant Proteins, pubmed-meshheading:15448155-Salts, pubmed-meshheading:15448155-Sequence Homology, Amino Acid
pubmed:year
2004
pubmed:articleTitle
One site mutation disrupts dimer formation in human DPP-IV proteins.
pubmed:affiliation
Division of Biotechnology and Pharmaceutical Research, National Health Research Institutes, Taipei 115, Taiwan, Republic of China.
pubmed:publicationType
Journal Article, In Vitro, Research Support, Non-U.S. Gov't