Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1996-2-20
pubmed:abstractText
A modified procedure employing a single chromatographic step to purify glutamine synthetase from human brain is described. The enzyme was characterized by native, denaturing, and two-dimensional gel electrophoresis and immunoblotting. Yield and purity were assessed by enzyme activity assay and a newly developed sandwich enzyme immunoassay using a mouse monoclonal antibody against native sheep brain glutamine synthetase. The immunoassay detected glutamine synthetase protein in samples where the enzyme had been inactivated by repeated cycles of freezing and thawing, and in serum and cerebrospinal fluid where glutamine synthetase was undetectable by the enzyme activity assay. Native glutamine synthetase from human brain occurred as an octamer with an estimated molecular weight of 360-400 kDa. Under reducing and denaturing conditions, the enzyme dissociated into monomeric subunits with an estimated molecular weight of 44 kDa. The monomers were recognized by the monoclonal antibody on immunoblots but not in the sandwich enzyme immunoassay, suggesting that the antigenic site occurs once on each subunit. Both human and sheep brain glutamine synthetases were composed of three and four different types of subunits with isoelectric points ranging from 7.0-7.2 and 6.8-7.0, respectively.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0022-1759
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
188
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
155-63
pubmed:dateRevised
2004-11-17
pubmed:meshHeading
pubmed:year
1995
pubmed:articleTitle
Purification and immunocharacterization of human brain glutamine synthetase and its detection in cerebrospinal fluid and serum by a sandwich enzyme immunoassay.
pubmed:affiliation
Specialty Laboratories, Inc., Santa Monica, CA 90404-3900, USA.
pubmed:publicationType
Journal Article