Linked Life Data

7819382

Source:http://linkedlifedata.com/resource/pubmed/id/7819382

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
8
pubmed:dateCreated
1995-2-10
pubmed:abstractText
Firefly luciferase has gained popularity as a protein model in elucidating anaesthesia mechanism because the bioluminescence of the purified enzyme system is extremely sensitive to volatile anaesthetics. This study analysed the thermal unfolding of firefly luciferase by differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FTIR). DSC showed that the transition of firefly luciferase from the folded (N) to unfolded (D) state occurred at 41.7 degrees C with the excess heat flow of 1.6 cal g-1 protein. Ethanol decreased the transition temperature dose dependently. In contrast, luciferin competitors, anilinonaphthalenesulphonate (ANS), toluidinonaphthalenesulphonate (TNS), and myristic acid increased the transition temperature. The competitive inhibitors antagonized unfolding and stabilized the N-state. Ethanol promoted unfolding and stabilized the D-state. Temperature scan by FTIR agreed with the DSC data. The intensities of amide-I' and amide-II' bands started to increase at 20-25 degrees C. This temperature coincides with the temperature where the bioluminescence of firefly luciferase is maximal. The unfolding effect of ethanol was evident even at 5 degrees C. ANS, TNS, and myristic acid completely protected the enzyme from the thermal unfolding. This is the first demonstration that the noncompetitive inhibitors induce the isothermal first-order phase transition in a functional protein, whereas competitive inhibitors protect the enzyme from thermal unfolding. The action mode of competitive inhibitors on firefly luciferase is completely different from that of noncompetitive inhibitors.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0731-7085
pubmed:author
pubmed:issnType
Print
pubmed:volume
12
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
969-75
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1994
pubmed:articleTitle
Ethanol unfolds firefly luciferase while competitive inhibitors antagonize unfolding: DSC and FTIR analyses.
pubmed:affiliation
Department of Anesthesia, DVA Medical Center, Salt Lake City, UT 84148.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, U.S. Gov't, Non-P.H.S.