Linked Life Data

6255327

Source:http://linkedlifedata.com/resource/pubmed/id/6255327

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1981-2-24
pubmed:abstractText
Epimastigote forms of Trypanosoma cruzi contain a soluble cAMP phosphodiesterase. Optimal activity was found at pH 8.0 and in the presence of 5 mM Mn2+. Other cations were less efficient and did not give rise to an additional stimulation when added in the presence of optimal concentrations of Mn2+. The enzyme is not Ca2+ dependent. The apparent Km of the enzyme for the substrate is 40 microM and no kinetic evidence for the existence of two enzymes has been found. Theophylline and caffein did not inhibit the T. cruzi cAMP phosphodiesterase. The enzyme activity does not change during cell growth suggesting that the fluctuation observed in the levels of cAMP are largely a response to variations in adenylyl cyclase activity. The intracellular concentrations of cAMP ranged between 0.04--0.15 microM. No evidence that the T. cruzi cAMP phosphodiesterase is regulated by an endogenous activator could be found. However, T. cruzi contains a heat-stable, low molecular weight, non-dialysable protein that activates mammalian cAMP phosphodiesterase in the presence of Ca2+. The properties so far studied of such an activator suggest that it might be equivalent to other Ca2+-dependent regulators described in vertebrate and invertebrate species.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0166-6851
pubmed:author
pubmed:issnType
Print
pubmed:volume
1
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
107-18
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed:year
1980
pubmed:articleTitle
cAMP phosphodiesterase and activator protein of mammalian cAMP phosphodiesterase from Trypanosoma cruzi.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't