Linked Life Data

11154067

Source:http://linkedlifedata.com/resource/pubmed/id/11154067

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
11
pubmed:dateCreated
2001-1-10
pubmed:abstractText
An iron-containing superoxide dismutase (SOD; EC 1.15.1.1) of the hyperthermophilic archaeon Acidianus ambivalens (Aa-SOD) has been purified and characterized and the gene has been cloned and sequenced. The SOD from the facultatively aerobic member of the crenarchaeota could be expressed in E. coli. Both, the native as well as the heterologously overproduced protein turned out to have extraordinarily high melting temperatures of 128 degrees C and 124.5 degrees C, respectively. To the best of our knowledge, this is the highest directly measured melting temperature of a native protein. Surprisingly, neither the native nor the recombinant superoxide dismutase displays 100% occupation of the metal coordination sites. Obviously it is not the incorporation of a metal ion that confers the extreme thermostability. Expression of the superoxide dismutase in the presence of different metals such as Fe, Co, Ni, Mn and Cu offered the possibility of studying the hitherto unknown cofactor preference of iron-superoxide dismutase. The recombinant enzyme displayed the highest preference for incorporation of cobalt although iron is used as the natural cofactor. Spectroscopic analysis by EPR, atomic absorption and UVNis spectroscopy as well as activity measurements and differential scanning calorimetry of the metal substituted superoxide dismutases were performed. However, the superoxide dismutase of A. ambivalens is active only with iron but may incorporate other metals equally well in the catalytic center without loss of conformational stability or heat tolerance. The co-form of the enzyme could be crystallized.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
1431-6730
pubmed:author
pubmed:issnType
Print
pubmed:volume
381
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1089-101
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2000
pubmed:articleTitle
The hyper-thermostable Fe-superoxide dismutase from the Archaeon Acidianus ambivalens: characterization, recombinant expression, crystallization and effects of metal exchange.
pubmed:affiliation
Institute of Biochemistry, Medical University of Lübeck, Germany.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't