Linked Life Data

10567415

Source:http://linkedlifedata.com/resource/pubmed/id/10567415

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
48
pubmed:dateCreated
1999-12-29
pubmed:abstractText
The eukaryotic 20 S proteasome is the prototype of a new family of the N-terminal nucleophil hydrolases and is composed of numerous low molecular mass subunits arranged in a stack of four rings, each containing seven different alpha- or beta-subunits. Among the beta-type subunits in the yeast proteasome, three proteolytically active ones were identified, although the functions of the other beta- and alpha-type subunits remain to be clarified. We report here that the purified 20 S proteasome exhibits intrinsic nucleoside diphosphate (NDP) kinase-like activity. The proteasome exhibited a preference for ATP and dATP as phosphate donors, and a broad specificity for NDPs, other than GDP, as phosphate acceptors, unlike conventional NDP kinase, which catalyzes the transfer of gamma-phosphate between NDPs and nucleoside triphosphates. During the transfer of gamma-phosphate, the proteasome formed acid-labile phosphohistidine as autophosphorylated intermediates, and NDP-dependent dephosphorylation of the latter then occurred. These enzymatic properties are similar to those of the molecular chaperone, Hsp70, which also exhibits intrinsic NDP kinase-like activity, instead of ATPase activity. C5 among the beta-type subunits and C8 among the alpha-type subunits were autophosphorylated during the gamma-phosphate transfer reaction and were photoaffinity labeled with 8-azido-[alpha-(32)P]ATP, suggesting that the C5 and C8 subunits of the proteasome are responsible for the NDP kinase-like activity.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
26
pubmed:volume
274
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
34375-82
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed-meshheading:10567415-Adenosine Diphosphate, pubmed-meshheading:10567415-Adenosine Triphosphate, pubmed-meshheading:10567415-Amino Acid Sequence, pubmed-meshheading:10567415-Cysteine Endopeptidases, pubmed-meshheading:10567415-Cytidine Diphosphate, pubmed-meshheading:10567415-Humans, pubmed-meshheading:10567415-Kinetics, pubmed-meshheading:10567415-Molecular Sequence Data, pubmed-meshheading:10567415-Multienzyme Complexes, pubmed-meshheading:10567415-Nucleoside-Diphosphate Kinase, pubmed-meshheading:10567415-Peptide Fragments, pubmed-meshheading:10567415-Phosphorylation, pubmed-meshheading:10567415-Proteasome Endopeptidase Complex, pubmed-meshheading:10567415-Sequence Analysis, Protein, pubmed-meshheading:10567415-Substrate Specificity, pubmed-meshheading:10567415-Tumor Cells, Cultured
pubmed:year
1999
pubmed:articleTitle
Intrinsic nucleoside diphosphate kinase-like activity is a novel function of the 20 S proteasome.
pubmed:affiliation
Division of Enzyme Chemistry, Institute for Enzyme Research, The University of Tokushima, Tokushima 770, Japan.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't