Linked Life Data

17904724

Source:http://linkedlifedata.com/resource/pubmed/id/17904724

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1-3
pubmed:dateCreated
2007-11-9
pubmed:abstractText
Solvent conditions play a major role in a wide range of physical properties of proteins in solution. Organic solvents, including dimethyl sulfoxide (DMSO), have been used to precipitate, crystallize and denature proteins. We have studied here the interactions of DMSO with proteins by differential refractometry and amino acid solubility measurements. The proteins used, i.e., ribonuclease, lysozyme, beta-lactoglobulin and chymotrypsinogen, all showed negative preferential DMSO binding, or preferential hydration, at low DMSO concentrations, where they are in the native state. As the DMSO concentration was increased, the preferential interaction changed from preferential hydration to preferential DMSO binding, except for ribonuclease. The preferential DMSO binding correlated with structural changes and unfolding of these proteins observed at higher DMSO concentrations. Amino acid solubility measurements showed that the interactions between glycine and DMSO are highly unfavorable, while the interactions of DMSO with aromatic and hydrophobic side chains are favorable. The observed preferential hydration of the native protein may be explained from a combination of the excluded volume effects of DMSO and the unfavorable interaction of DMSO with a polar surface, as manifested by the unfavorable interactions of DMSO with the polar uncharged glycine molecule. Such an unfavorable interaction of DMSO with the native protein correlates with the enhanced self-association and precipitation of proteins by DMSO. Conversely, the observed conformational changes at higher DMSO concentration are due to increased binding of DMSO to hydrophobic and aromatic side chains, which had been newly exposed on protein unfolding.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0301-4622
pubmed:author
pubmed:issnType
Print
pubmed:volume
131
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
62-70
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed:year
2007
pubmed:articleTitle
Protein precipitation and denaturation by dimethyl sulfoxide.
pubmed:affiliation
Alliance Protein Laboratories, Thousand Oaks, CA 91360, USA. tarakawa2@aol.com
pubmed:publicationType
Journal Article, Research Support, N.I.H., Extramural