| pubmed-article:18234223 | rdf:type | pubmed:Citation | lld:pubmed |
| pubmed-article:18234223 | lifeskim:mentions | umls-concept:C0205103 | lld:lifeskim |
| pubmed-article:18234223 | lifeskim:mentions | umls-concept:C1538046 | lld:lifeskim |
| pubmed-article:18234223 | lifeskim:mentions | umls-concept:C1853685 | lld:lifeskim |
| pubmed-article:18234223 | lifeskim:mentions | umls-concept:C1514562 | lld:lifeskim |
| pubmed-article:18234223 | lifeskim:mentions | umls-concept:C1883221 | lld:lifeskim |
| pubmed-article:18234223 | lifeskim:mentions | umls-concept:C1704259 | lld:lifeskim |
| pubmed-article:18234223 | lifeskim:mentions | umls-concept:C1705987 | lld:lifeskim |
| pubmed-article:18234223 | lifeskim:mentions | umls-concept:C0185026 | lld:lifeskim |
| pubmed-article:18234223 | lifeskim:mentions | umls-concept:C1883204 | lld:lifeskim |
| pubmed-article:18234223 | lifeskim:mentions | umls-concept:C1705294 | lld:lifeskim |
| pubmed-article:18234223 | lifeskim:mentions | umls-concept:C1880389 | lld:lifeskim |
| pubmed-article:18234223 | lifeskim:mentions | umls-concept:C0173022 | lld:lifeskim |
| pubmed-article:18234223 | pubmed:issue | 5 | lld:pubmed |
| pubmed-article:18234223 | pubmed:dateCreated | 2008-2-18 | lld:pubmed |
| pubmed-article:18234223 | pubmed:abstractText | The 90-residue N-terminal Phox and Bem1p (PB1) domain of NBR1 forms an alpha/beta ubiquitin-like fold. Kinetic analysis using stopped-flow fluorescence reveals two-state kinetics; however, nonlinear effects in the denaturant dependence of the unfolding data demonstrate changes in the position of the rate-limiting barrier along the folding coordinate as the folding conditions change. The kinetics of wt-PB1 and several mutants show that this curvature is consistent with a single-pathway mechanism involving sequential transition states (TS1 and TS2) separated by a transiently populated high-energy intermediate, rather than movement of the transition state on a broad energy plateau. We show that the two transition states within the sequential model represent structurally and thermodynamically distinct species. TS1 is a collapsed state (alpha(TS1)=0.71) with a large enthalpic barrier to formation that is rate-limiting under conditions that strongly favour folding. TS2 is highly native-like (alpha(TS2)=0.93) and represents a late entropic barrier to formation of the native state. In support of the sequential transition state mechanism, we show that the G62A helix 2 substitution stabilises TS1 and the intermediate to such an extent that the latter becomes significantly populated, leading to the observation of a fast kinetic phase representing the initial U-->I transition, with TS2 (alpha(TS2)=0.87) becoming rate-limiting. The folding rate is not retarded by populating an intermediate, which would be expected for a misfold state, but is accelerated, suggesting that the I state is productive and on-pathway. The results show that the apparent two-state folding of the wt-PB1 domain occurs along a well-defined pathway involving structurally and thermodynamically distinct sequential transition states and an obligatory metastable intermediate that represents a productive local minimum in the energy landscape that increases the efficiency of barrier crossing through favourable effects on the entropy of activation. | lld:pubmed |
| pubmed-article:18234223 | pubmed:language | eng | lld:pubmed |
| pubmed-article:18234223 | pubmed:journal | http://linkedlifedata.com/r... | lld:pubmed |
| pubmed-article:18234223 | pubmed:citationSubset | IM | lld:pubmed |
| pubmed-article:18234223 | pubmed:chemical | http://linkedlifedata.com/r... | lld:pubmed |
| pubmed-article:18234223 | pubmed:chemical | http://linkedlifedata.com/r... | lld:pubmed |
| pubmed-article:18234223 | pubmed:status | MEDLINE | lld:pubmed |
| pubmed-article:18234223 | pubmed:month | Mar | lld:pubmed |
| pubmed-article:18234223 | pubmed:issn | 1089-8638 | lld:pubmed |
| pubmed-article:18234223 | pubmed:author | pubmed-author:ChenPingP | lld:pubmed |
| pubmed-article:18234223 | pubmed:author | pubmed-author:SearleMark... | lld:pubmed |
| pubmed-article:18234223 | pubmed:author | pubmed-author:LongJedJ | lld:pubmed |
| pubmed-article:18234223 | pubmed:issnType | Electronic | lld:pubmed |
| pubmed-article:18234223 | pubmed:day | 7 | lld:pubmed |
| pubmed-article:18234223 | pubmed:volume | 376 | lld:pubmed |
| pubmed-article:18234223 | pubmed:owner | NLM | lld:pubmed |
| pubmed-article:18234223 | pubmed:authorsComplete | Y | lld:pubmed |
| pubmed-article:18234223 | pubmed:pagination | 1463-77 | lld:pubmed |
| pubmed-article:18234223 | pubmed:meshHeading | pubmed-meshheading:18234223... | lld:pubmed |
| pubmed-article:18234223 | pubmed:meshHeading | pubmed-meshheading:18234223... | lld:pubmed |
| pubmed-article:18234223 | pubmed:meshHeading | pubmed-meshheading:18234223... | lld:pubmed |
| pubmed-article:18234223 | pubmed:meshHeading | pubmed-meshheading:18234223... | lld:pubmed |
| pubmed-article:18234223 | pubmed:meshHeading | pubmed-meshheading:18234223... | lld:pubmed |
| pubmed-article:18234223 | pubmed:meshHeading | pubmed-meshheading:18234223... | lld:pubmed |
| pubmed-article:18234223 | pubmed:meshHeading | pubmed-meshheading:18234223... | lld:pubmed |
| pubmed-article:18234223 | pubmed:meshHeading | pubmed-meshheading:18234223... | lld:pubmed |
| pubmed-article:18234223 | pubmed:meshHeading | pubmed-meshheading:18234223... | lld:pubmed |
| pubmed-article:18234223 | pubmed:year | 2008 | lld:pubmed |
| pubmed-article:18234223 | pubmed:articleTitle | Sequential barriers and an obligatory metastable intermediate define the apparent two-state folding pathway of the ubiquitin-like PB1 domain of NBR1. | lld:pubmed |
| pubmed-article:18234223 | pubmed:affiliation | Centre for Biomolecular Sciences, School of Chemistry, University Park, Nottingham, NG7 2RD, UK. | lld:pubmed |
| pubmed-article:18234223 | pubmed:publicationType | Journal Article | lld:pubmed |
| pubmed-article:18234223 | pubmed:publicationType | Research Support, Non-U.S. Gov't | lld:pubmed |
