Linked Life Data

10707022

Source:http://linkedlifedata.com/resource/pubmed/id/10707022

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
2000-4-7
pubmed:abstractText
The esterase from the hyperthermophilic archaeon Archaeoglobus fulgidus is a monomeric protein with a molecular weight of about 35.5 kDa. The enzyme is barely active at room temperature, displaying the maximal enzyme activity at about 80 degrees C. We have investigated the effect of the temperature on the protein structure by Fourier-transform infrared spectroscopy. The data show that between 20 degrees C and 60 degrees C a small but significant decrease of the beta-sheet bands occurred, indicating a partial loss of beta-sheets. This finding may be surprising for a thermophilic protein and suggests the presence of a temperature-sensitive beta-sheet. The increase in temperature from 60 degrees C to 98 degrees C induced a decrease of alpha-helix and beta-sheet bands which, however, are still easily detected at 98 degrees C indicating that at this temperature some secondary structure elements of the protein remain intact. The conformational dynamics of the esterase were investigated by frequency-domain fluorometry and anisotropy decays. The fluorescence studies showed that the intrinsic tryptophanyl fluorescence of the protein was well represented by the three-exponential model, and that the temperature affected the protein conformational dynamics. Remarkably, the tryptophanyl fluorescence emission reveals that the indolic residues remained shielded from the solvent up to 80 degrees C, as shown from the emission spectra and by acrylamide quenching experiments. The relationship between enzyme activity and protein structure is discussed.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0887-3585
pubmed:author
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
38
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
351-60
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
2000
pubmed:articleTitle
The thermophilic esterase from Archaeoglobus fulgidus: structure and conformational dynamics at high temperature.
pubmed:affiliation
University of Maryland School of Medicine, Department of Biochemistry and Molecular Biology, Baltimore, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't