Linked Life Data

24462

Source:http://linkedlifedata.com/resource/pubmed/id/24462

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
1978-5-17
pubmed:abstractText
The reaction of glutamate dehydrogenase with two different stable nitroxides (spin labels) is reported. The two compounds contain a carbonyl and an iodoacetamide group as their reactive parts. The carbonyl compound inactivates the enzyme by the formation of a 1:1 covalent complex after NaBH4 reduction of an intermediate Schiff's base. Evidence indicates that the enzyme is modified at lysine-126 in the active site. The electron spin resonance (ESR) spectrum of spin-labeled enzyme indicates a high degree of immobilization of the nitroxide. The binding of reduced coenzyme NADPH is reflected by a change (immobilization) of the ESR spectrum. Nuclear relaxation of bound substrate, oxidized coenzyme, and inhibitor by the paramagnetic group is observed. This shows the existence of a binding site for these compounds close to the active site. The distances of selected protons of the binding ligands to the nitroxide are calculated. The iodoacetamide spin label reacts with several groups, one of which is not a sulfhydryl. The reaction of this particular group causes inactivation of the enzyme. Protection against this inactivation could be achieved with certain ligands. Only enzyme that was spin labeled without such protection caused paramagnetic relaxation of bound substrate and coenzyme.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0006-2960
pubmed:author
pubmed:issnType
Print
pubmed:day
7
pubmed:volume
17
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
778-83
pubmed:dateRevised
2003-11-14
pubmed:meshHeading
pubmed:year
1978
pubmed:articleTitle
Electron spin resonance and nuclear relaxation studies on spin-labeled glutamate dehydrogenase.
pubmed:publicationType
Journal Article