Linked Life Data

1885588

Source:http://linkedlifedata.com/resource/pubmed/id/1885588

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
25
pubmed:dateCreated
1991-10-4
pubmed:abstractText
We have analyzed the functional domain structure of rat mammary glucosidase I, an enzyme involved in N-linked glycoprotein processing, using biochemical and immunological approaches. The enzyme contains a high mannose type sugar chain that can be cleaved by endo-beta-N-acetyl-D-glucosaminidase H without significantly affecting the catalytic activity. Based on trypsin digestion pattern and the data on membrane topography, glucosidase I constitutes a single polypeptide chain of 85 kDa with two contiguous domains: a membrane-bound domain that anchors the protein to the endoplasmic reticulum and a luminal domain. A catalytically active 39-kDa domain could be released from membranes by limited proteolysis of saponin-permeabilized membranes with trypsin. This domain appeared to contain the active site of the enzyme and had the ability to bind to glucosidase I-specific affinity gel. Phase partitioning with Triton X-114 indicated the amphiphilic nature of the native enzyme, consistent with its location as an integral membrane protein, whereas the 39-kDa fragment partitioned in the aqueous phase, a characteristic of soluble polypeptide. These results indicate that glucosidase I is a transmembrane protein with a luminally oriented catalytic domain. Such an orientation of the catalytic domain may facilitate the sequential processing of asparagine-linked oligosaccharide, soon after its transfer en bloc by the oligosaccharyl transferase complex in the lumen of endoplasmic reticulum.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
5
pubmed:volume
266
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
16587-93
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1991
pubmed:articleTitle
Glucosidase I, a transmembrane endoplasmic reticular glycoprotein with a luminal catalytic domain.
pubmed:affiliation
Department of Animal Sciences, University of Maryland, College Park 20742.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't