Linked Life Data

11300776

Source:http://linkedlifedata.com/resource/pubmed/id/11300776

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
13
pubmed:dateCreated
2001-4-13
pubmed:abstractText
The denatured states of a small globular protein, apo-neocarzinostatin (NCS), have been characterized using several techniques. Structural properties were investigated by optical spectroscopy techniques and small-angle neutron scattering (SANS), as a function of guanidinium chloride (GdmCl) concentration. SANS experiments show that in heavy water, the protein keeps its native size at GdmCl concentrations below 2.5 M. A sharp transition occurs at about 3.6 M GdmCl, and NCS behaves like an excluded volume chain above 5 M. The same behavior is observed in deuterated buffer by fluorescence and circular dichroism measurements. For the H(2)O buffer, the transition occurs with lower concentration of denaturant, the shift being about 0.6 M. 8-Anilino-1-naphthalenesulfonate (ANS) was used as a hydrophobic fluorescent probe for studying the early stages of protein unfolding. Protein denaturation modifies the fluorescence intensity of ANS, a maximum of intensity being detected close to 2 M GdmCl in hydrogenated buffer, which shows the existence of at least one intermediate state populated at the beginning of the unfolding pathway. Differential scanning calorimetry (DSC) was used to obtain thermodynamic values for NCS denaturation. The melting curves recorded between 20 and 90 degrees C in the presence of various GdmCl concentrations (0-3 M) cannot be explained by a simple two-state model. Altogether, the data presented in this paper suggest that before unfolding the protein explores a distribution of states which is centered around compact states at denaturant concentrations below 2 M in H(2)O, and then shifts to less structured states by increasing denaturant concentrations.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0006-2960
pubmed:author
pubmed:issnType
Print
pubmed:day
3
pubmed:volume
40
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
3958-66
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2001
pubmed:articleTitle
Characterization of the denatured states distribution of neocarzinostatin by small-angle neutron scattering and differential scanning calorimetry.
pubmed:affiliation
Laboratoire Léon Brillouin, CE-Saclay, 91191 Gif-sur-Yvette Cedex, France.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't