Linked Life Data

16237198

Source:http://linkedlifedata.com/resource/pubmed/id/16237198

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
2006-1-13
pubmed:abstractText
The synthesis of N-acetylneuraminate (Neu5Ac), the main form of sialic acid, proceeds in vertebrates through the condensation of N-acetylmannosamine 6-phosphate and phosphoenolpyruvate to Neu5Ac-9-phosphate, followed by the dephosphorylation of the latter by a specific phosphatase. The sequence encoding Neu5Ac-9-phosphate phosphatase (Neu5Ac-9-Pase; E.C. 3.1.3.29) has not been determined until now. In this work, we have purified Neu5Ac-9-Pase more than 1000-fold from rat liver. Its dependency on Mg2+ and the fact that it was inhibited by vanadate and Ca2+ suggested that it belonged to the haloacid dehalogenase family of phosphatases. Trypsin digestion and mass spectrometry analysis of a polypeptide of about 30 kDa that co-eluted with the activity in the last purification step indicated the presence of a protein designated "haloacid dehalogenase-like hydrolase domain containing 4." The human ortholog of this protein is encoded by a 2-exon gene present on chromosome 20p11. The human protein was overexpressed in Escherichia coli as a fusion protein with a polyHis tag and purified to homogeneity. The recombinant enzyme displayed a >230-fold higher catalytic efficiency on Neu5Ac-9-phosphate than on its second best substrate. Its properties were similar to those of the enzyme purified from rat liver. Neu5Ac inhibited the enzymatic activity by 50% at 15 mM, indicating that no significant inhibition is exerted at physiological concentrations of Neu5Ac. The identification of the gene encoding Neu5Ac-9-Pase will facilitate studies aimed at testing its potential implication in unexplained forms of glycosylation deficiency.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0959-6658
pubmed:author
pubmed:issnType
Print
pubmed:volume
16
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
165-72
pubmed:meshHeading
pubmed:year
2006
pubmed:articleTitle
Identification of the sequence encoding N-acetylneuraminate-9-phosphate phosphatase.
pubmed:affiliation
Laboratory of Physiological Chemistry, Université Catholique de Louvain and the Christian de Duve Institute of Cellular Pathology, Avenue Hippocrate 75, B-1200 Brussels, Belgium.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't