Linked Life Data

6313064

Source:http://linkedlifedata.com/resource/pubmed/id/6313064

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1983-12-17
pubmed:abstractText
We have investigated the enzymatic formation of S-adenosylmethionine in extracts of a variety of normal and oncogenically-transformed human and rat cell lines which differ in their ability to grow in medium in which methionine is replaced by its immediate precursor homocysteine. We have localized the bulk of the S-adenosylmethionine synthetase activity to the post-mitochondrial supernatant. We show that in all cell lines a single kinetic species exists in a dialyzed extract with a Km for methionine of about 3-12 microM. In selected lines we have demonstrated a requirement for Mg2+ in addition to that needed to form the Mg X ATP complex for enzyme activity and have shown that the enzyme can be regulated by product feedback inhibition. Because we detect no differences in the enzymatic ability of these cell extracts to utilize methionine for S-adenosylmethionine formation in vitro, we suggest that the failure of oncogenically-transformed cell lines to grow in homocysteine medium may result from the decreased methionine pools in these cells or from the loss of ability of these cells to properly metabolize homocysteine, adenosine, or their cellular product S-adenosylhomocysteine.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0006-3002
pubmed:author
pubmed:issnType
Print
pubmed:day
18
pubmed:volume
760
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
270-7
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
1983
pubmed:articleTitle
S-adenosylmethionine synthetase in cultured normal and oncogenically-transformed human and rat cells.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't