Linked Life Data

15491624

Source:http://linkedlifedata.com/resource/pubmed/id/15491624

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
2004-10-19
pubmed:abstractText
Unless the native conformation has an unstructured region, proteases cannot effectively digest a protein under native conditions. Digestion must occur from a higher energy form, when at least some part of the protein is exposed to solvent and becomes accessible by proteases. Monitoring the kinetics and denaturant dependence of proteolysis under native conditions yields insight into the mechanism of proteolysis as well as these high-energy conformations. We propose here a generalized approach to exploit proteolysis as a tool to probe high-energy states in proteins. This "native state proteolysis" experiment was carried out on Escherichia coli ribonuclease HI. Mass spectrometry and N-terminal sequencing showed that thermolysin cleaves the peptide bond between Thr92 and Ala93 in an extended loop region of the protein. By comparing the proteolysis rate of the folded protein and a peptidic substrate mimicking the sequence at the cleavage site, the energy required to reach the susceptible state (Delta G(proteolysis)) was determined. From the denaturant dependence of Delta G(proteolysis), we determined that thermolysin digests this protein through a local fluctuation, i.e. localized unfolding with minimal change in solvent assessable surface area. Proteolytic susceptibilities of proteins are discussed based on the finding of this local fluctuation mechanism for proteolysis under native conditions.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0022-2836
pubmed:author
pubmed:issnType
Print
pubmed:day
5
pubmed:volume
343
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1467-76
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed:year
2004
pubmed:articleTitle
Probing the high energy states in proteins by proteolysis.
pubmed:affiliation
Department of Molecular and Cell Biology, QB3 Institute, University of California, Berkeley, CA 94720, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.