Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1998-8-18
pubmed:abstractText
The effects of temperature on the three-dimensional organization and on the secondary structure of GPI-anchored 5'-nucleotidase from bull seminal plasma and of its anchor-less form (solubilized ecto-5'-nucleotidase), obtained after GPI anchor removal by phosphatidylinositol-specific phospholipase C were investigated in parallel by circular dichroism and fluorescence spectroscopy. The structural features of the two enzymes were correlated to their functional properties in the temperature range of 25-90 degrees C. The kinetic data indicated that the enzyme activities were temperature dependent, showing the maximal values at 60 degrees C. The relevant Arrhenius plots were linear in the temperature range of 20-60 degrees C and the activation energies were 44.4 and 51.8 kJ/mol for the solubilized and GPI-anchored 5'-nucleotidase, respectively. The time-course measurements of enzyme activity, in the temperature range of 25-55 degrees C, revealed that the two enzymes were of different thermal stability, the solubilized ectoenzyme showing lower thermal deactivation constants and longer half lives. Fluorescence and near UV circular dichroism spectroscopy showed that temperature increases induced remarkable changes in the protein tertiary structure of the two enzymes, whereas far-UV circular dichroism analysis revealed only a small temperature effect on the protein secondary structure content.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0021-924X
pubmed:author
pubmed:issnType
Print
pubmed:volume
123
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
269-74
pubmed:dateRevised
2007-12-19
pubmed:meshHeading
pubmed:year
1998
pubmed:articleTitle
Temperature effects on the structural and functional properties of GPI-anchored and anchor-less bull seminal plasma ecto-5'-nucleotidase.
pubmed:affiliation
Dipartimento di Biologia Cellulare e Molecolare, Università di Perugia, Italy. cfini@unipg.it
pubmed:publicationType
Journal Article, Comparative Study, Research Support, Non-U.S. Gov't