Linked Life Data

10432184

Source:http://linkedlifedata.com/resource/pubmed/id/10432184

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
1999-10-15
pubmed:abstractText
Polyamines are known to play an essential role in cell growth and differentiation. In animals, putrescine is mainly synthesized from ornithine by ornithine decarboxylase (ODC). In higher plants and in bacteria putrescine can also be synthesized from arginine by arginine decarboxylase (ADC). In this paper we report the presence of significant levels of ADC activity in crude extracts of Trypanosoma cruzi, RA strain epimastigotes. ADC activity was detected during a very narrow time range, corresponding to the early logarithmic growth phase. This activity was inhibited by DL-alpha-difluoromethylarginine, a specific irreversible inhibitor of ADC and activated by DL-alpha-difluoromethylornithine, a specific irreversible inhibitor of ODC. The reaction showed an absolute requirement for pyridoxal phosphate, dithiothreitol and Mg++. The enzyme half life was about 10 hrs., showed maximum activity at pH 7.9 and a Km for arginine of 5 mM. ADC activity was stimulated by fetal-calf-serum and inhibited by spermine, probably through a negative feed-back regulation on the levels of the enzyme. ODC activity was not detected. These results confirm our previous reports on the capability of T. cruzi, RA strain epimastigotes to synthesize putrescine from arginine via agmatine by ADC and point out differences on polyamine metabolism between the parasite and the mammalian host cell.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0145-5680
pubmed:author
pubmed:issnType
Print
pubmed:volume
45
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
383-91
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1999
pubmed:articleTitle
Arginine decarboxylase in Trypanosoma cruzi, characteristics and kinetic properties.
pubmed:affiliation
Departamento de Bioquímica Humana, Facultad de Medicina, Universidad de Buenos Aires, Republica Argentina.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't