Linked Life Data

3089333

Source:http://linkedlifedata.com/resource/pubmed/id/3089333

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
7
pubmed:dateCreated
1986-9-25
pubmed:abstractText
The presence of two forms (high and low molecular weight ones) of purine nucleoside phosphorylase II (purine nucleoside: orthophosphate ribosyltransferase, EC 2.4.2.1) was demonstrated. The high molecular weight form of the enzyme was purified, and the properties of both forms were compared. The enzyme forms were shown to differ in their quaternary structure (trimeric and hexameric), molecular weight of the native enzyme and its subunits (85,000 and 28,000 for the trimer, 150,000 and 25,000 for the hexamer, respectively) as well as substrate specificity (the trimer is specific for all major purine nucleosides, while the hexamer does not cleave adenine nucleosides). Adenosine is a competitive inhibitor of the hexameric form with respect to deoxyguanosine (Ki = 1.16 X 10(-3) M); the Km value for deoxyguanosine is 9.85 X 10(-5) M. The isoelectric point for the both forms of the enzyme in the presence of 9 M urea is about 5.5. Both forms have a pH optimum of phosphorolytic activity between 6.5 and 7.0.
pubmed:language
rus
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0320-9725
pubmed:author
pubmed:issnType
Print
pubmed:volume
51
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1085-92
pubmed:dateRevised
2007-7-23
pubmed:meshHeading
pubmed:year
1986
pubmed:articleTitle
[Isolation of the hexameric form of purine nucleoside phosphorylase from E. coli. Comparative study of trimeric and hexameric forms of the enzyme].
pubmed:publicationType
Journal Article, Comparative Study, English Abstract