Linked Life Data

6457829

Source:http://linkedlifedata.com/resource/pubmed/id/6457829

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
23
pubmed:dateCreated
1982-1-28
pubmed:abstractText
Lysosomal enzymes contain 6-phosphomannosyl moieties which mediate their translocation to lysosomes. This recognition marker is synthesized by the sequential action of UDP-N-acetylglucosamine:lysosomal enzyme N-acetylglucosamine-1-phosphotransferase and alpha-N-acetylglucosaminyl phosphodiesterase. A new assay for the N-acetylglucosaminylphosphotransferase, using alpha-methylmannoside as acceptor, is presented. Using this assay, we partially purified the transferase and examined its substrate specificity. The transferase exhibited a very high affinity toward lysosomal enzymes (apparent Km values of less than 20 microM) and was greater than 100-fold more efficient (Vmax/Km) when using lysosomal enzymes as acceptors as compared to nonlysosomal glycoproteins that contain high mannose oligosaccharide units. Heat denaturation of the lysosomal enzymes resulted in the loss of acceptor activity. The model compounds alpha-methylmannoside and Man5--8GlcNAc were poor acceptors. We propose that this enzyme catalyzes the initial, determining step by which synthesized acid hydrolases are distinguished from other newly synthesized glycoproteins and thus are eventually targeted to lysosomes.
pubmed:grant
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
256
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
11977-80
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed:year
1981
pubmed:articleTitle
Lysosomal enzyme targeting. N-Acetylglucosaminylphosphotransferase selectively phosphorylates native lysosomal enzymes.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.