Linked Life Data

2891356

Source:http://linkedlifedata.com/resource/pubmed/id/2891356

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1987-12-28
pubmed:abstractText
The effect of spermine on tyrosine hydroxylase (TH) activity purified from bovine adrenal medulla was examined before and after phosphorylation by the catalytic subunit of cyclic AMP-dependent protein kinase (A-kinase). Before phosphorylation, spermine (less than 1 mM) inhibited the enzymatic activity, and negative cooperative effect of spermine on TH (Hill coefficient = 0.7) was observed from the kinetic analysis concerning 6-methyl-5,6,7,8-tetrahydropterin (6MPH4). Spermine interacted noncompetitively toward tyrosine and the Ki for spermine was calculated to be 68 microM. Phosphorylation abolished the ability of spermine to inhibit TH activity in a negative cooperative manner against the pterin cofactor, and also increased four-fold the Ki value against the substrate. These results suggest that spermine may inhibit TH activity by interacting with the pterin binding site of the enzyme molecule in a manner of negative cooperativity, and that this inhibition is reversed by the conformational change of regulatory domain of TH after phosphorylation by A-kinase.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0006-291X
pubmed:author
pubmed:issnType
Print
pubmed:day
13
pubmed:volume
148
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1460-7
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed:year
1987
pubmed:articleTitle
Effect of spermine on tyrosine hydroxylase activity before and after phosphorylation by cyclic AMP-dependent protein kinase.
pubmed:affiliation
Department of Biochemistry, Nagoya University School of Medicine, Japan.
pubmed:publicationType
Journal Article, In Vitro, Research Support, Non-U.S. Gov't