Structural Dynamics of Free Proteins in Diffraction.
Among the macromolecular patterns of biological significance, right-handed a-helices are perhaps the most abundant structural motifs. Here, guided by experimental findings, we discuss both ultrafast initial steps and longer-time-scale structural dynamics of helix-coil transitions induced by a range...
| Publicado en: | Journal of the American Chemical Society Vol. 133; no. 42; pp. 17072 - 17087 |
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| Autores principales: | , , |
| Formato: | Artículo |
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American Chemical Society
10/26/2011
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| Acceso en línea: | Ver este registro en EBSCOhost |
| fields | @attributes: recordID: 1 pdfLink: plink: https://search.ebscohost.com/login.aspx?direct=true&db=hlh&AN=67152613&site=ehost-live header: @attributes: shortDbName: hlh uiTerm: 67152613 longDbName: Humanities International Complete uiTag: AN controlInfo: bkinfo: jinfo: jid: 00027863 ACS jtl: Journal of the American Chemical Society issn: 00027863 maglogo: N pubinfo: dt: 10/26/2011 vid: 133 iid: 42 pid: 997 pub: American Chemical Society artinfo: ui: 67152613 10.1021/ja207722k ppf: 17072 ppct: 15 formats: tig: atl: Structural Dynamics of Free Proteins in Diffraction. aug: au: Lin, Milo M. Shorokbov, Dmitry Zewail, Ahmed H. affil: Physical Biology Center for Ultrafast Science and Technology, Arthur Amos Noyes Laboratory for Chemical Physics, California Institute of Technology, Pasadena, California 91125, United States su: Structural dynamics Optical diffraction Helices (Algebraic topology) Thymosin Polypeptides sug: subj: Structural dynamics Optical diffraction Helices (Algebraic topology) Thymosin Polypeptides ab: Among the macromolecular patterns of biological significance, right-handed a-helices are perhaps the most abundant structural motifs. Here, guided by experimental findings, we discuss both ultrafast initial steps and longer-time-scale structural dynamics of helix-coil transitions induced by a range of temperature jumps in large, isolated macromolecular ensembles of an a-helical protein segment thymosin β (Tβ), and elucidate the comprehensive picture of (un)folding. In continuation of an earlier theoretical work from this laboratory that utilized a simplistic structure-scrambling algorithm combined with a variety of self-avoidance thresholds to approximately model helix-coil transitions in Tβ, in the present contribution we focus on the actual dynamics of unfolding as obtained from massively distributed ensemble-convergent MD simulations which provide an unprecedented scope of information on the nature of transient macromolecular structures, and with atomic-scale spatiotemporal resolution. In addition to the use of radial distribution functions of ultrafast electron diffraction (UED) simulations in gaining an insight into the elementary steps of conformational interconversions, we also investigate the structural dynamics of the protein via the native (a-helical) hydrogen bonding contact metric which is an intuitive coarse graining approach. Importantly, the decay of a-helical motifs and the (globular) conformational annealing in Tβ occur consecutively or competitively, depending on the magnitude of temperature jump. pubtype: Academic Journal doctype: Article src: R language: English refInfo: copyright: @attributes: flag: Y dt: @attributes: year: 2011 holdings: @attributes: islocal: N |
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