Linked Life Data

16670083

Source:http://linkedlifedata.com/resource/pubmed/id/16670083

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
27
pubmed:dateCreated
2006-7-3
pubmed:abstractText
Fructosamine-3-kinase (FN3K) is a recently described protein-repair enzyme responsible for the removal of fructosamines, which are the products of a spontaneous reaction of glucose with amines. We show here that, compared with glucose, glucose 6-phosphate (Glu-6-P) reacted 3-6-fold more rapidly with proteins and 8-fold more rapidly with N-alpha-t-Boc-lysine, being therefore a more significant intracellular glycating agent than glucose in skeletal muscle and heart. Fructosamine 6-phosphates, which result from the reaction of amines with Glu-6-P, were not substrates for FN3K. However, a phosphatase that dephosphorylates protein-bound fructosamine 6-phosphates was found to be present in rat tissues. This enzyme was purified to near homogeneity from skeletal muscle and was identified as magnesium-dependent phosphatase-1 (MDP-1), an enzyme of the haloacid dehalogenase family with a putative protein-tyrosine phosphatase function. Human recombinant MDP-1 acted on protein-bound fructosamine 6-phosphates with a catalytic efficiency >10-fold higher than those observed with its next best substrates (arabinose 5-phosphate and free fructoselysine 6-phosphate) and >100-fold higher than with protein-phosphotyrosine. It had no detectable activity on fructosamine 3-phosphates. MDP-1 dephosphorylated up to approximately 75% of the fructosamine 6-phosphates that are present on lysozyme after incubation of this protein with Glu-6-P. Furthermore, lysozyme glycated with Glu-6-P was converted by MDP-1 to a substrate for FN3K. We conclude that MDP-1 may act physiologically in conjunction with FN3K to free proteins from the glycation products derived from Glu-6-P.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
7
pubmed:volume
281
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
18378-85
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed:year
2006
pubmed:articleTitle
Magnesium-dependent phosphatase-1 is a protein-fructosamine-6-phosphatase potentially involved in glycation repair.
pubmed:affiliation
Laboratory of Physiological Chemistry, Christian de Duve Institute of Cellular Pathology and Université Catholique de Louvain, Brussels, Belgium.
pubmed:publicationType
Journal Article, Comparative Study, In Vitro, Research Support, Non-U.S. Gov't