Linked Life Data

6838817

Source:http://linkedlifedata.com/resource/pubmed/id/6838817

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1983-6-10
pubmed:abstractText
Dihydrofolate reductase has been isolated from methotrexate-resistant WIL2 human lymphoblastoid cells. This subline produces ca. 150 times more enzyme than the parental drug-sensitive line. The reductase has been purified to homogeneity by methotrexate affinity chromatography, gel filtration, and preparative isoelectric focusing in a yield of 65%. The enzyme has a pI = 7.7 and a molecular weight of ca. 22000. The amino-terminal 27 amino acid residues have been determined, revealing the location of the single cysteine residue at position 6. Reaction of this cysteine with p-(hydroxy-mercuri)benzoate in the presence of reduced nicotinamide adenine dinucleotide phosphate (NADPH) results in a 5-fold increase in enzyme activity. Other agents including KCl, urea, and thiourea also cause enzyme activation. The Km values for NADPH and dihydrofolate are 0.25 and 0.036 microM, respectively. Mercurial activation of the enzyme results in a 27-fold increase in the Km for NADPH and a 35-fold increase in the Km for dihydrofolate.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0006-2960
pubmed:author
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
22
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
633-9
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1983
pubmed:articleTitle
Purification and characterization of dihydrofolate reductase from methotrexate-resistant human lymphoblastoid cells.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.