Linked Life Data

18385137

Source:http://linkedlifedata.com/resource/pubmed/id/18385137

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
22
pubmed:dateCreated
2008-5-26
pubmed:databankReference
pubmed:abstractText
Human extracellular superoxide dismutase (EC-SOD) is a tetrameric glycoprotein responsible for the removal of superoxide generated in the extracellular space. Two different folding variants of EC-SOD exist based on the disulfide bridge connectivity, resulting in enzymatically active (aEC-SOD) and inactive (iEC-SOD) subunits. As a consequence of this, the assembly of the EC-SOD tetramers produces molecules with variable activity and may represent a way to regulate the antioxidant level in the extracellular space. To determine whether the formation of these two folding variants is an intra- or extracellular event, we analyzed the biosynthesis in human embryonic kidney 293 cells expressing wild-type EC-SOD. These analyses revealed that both folding variants were present in the intra- and extracellular spaces, suggesting that the formation is an intracellular event. To further analyze the biosynthesis, we constructed mutants with the capacity to generate only aEC-SOD (C195S) or iEC-SOD (C45S). The expression of these suggested that the cellular biosynthetic machinery supported the secretion of aEC-SOD but not iEC-SOD. The coexpression of these two mutants did not affect the expression pattern. This study shows that generation of the EC-SOD folding variants is an intracellular event that depends on a free cysteine residue not involved in disulfide bonding.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
30
pubmed:volume
283
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
15031-6
pubmed:meshHeading
pubmed:year
2008
pubmed:articleTitle
The folding of human active and inactive extracellular superoxide dismutases is an intracellular event.
pubmed:affiliation
Center for Insoluble Protein Structures and Interdisciplinary Nanoscience Center, Departments of Molecular Biology and Chemistry, University of Aarhus, Aarhus, Denmark.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't