Computational Amide I Spectroscopy from the ground up : building and benchmarking new tools to study disordered peptide ensembles

Thesis: Ph. D. in Physical Chemistry, Massachusetts Institute of Technology, Department of Chemistry, 2016.

Bibliographic Details
Main Author: Reppert, Michael Earl
Other Authors: Andrei Tokmakoff.
Format: Thesis
Language:eng
Published: Massachusetts Institute of Technology 2016
Subjects:
Online Access:http://hdl.handle.net/1721.1/105045
_version_ 1826216753663836160
author Reppert, Michael Earl
author2 Andrei Tokmakoff.
author_facet Andrei Tokmakoff.
Reppert, Michael Earl
author_sort Reppert, Michael Earl
collection MIT
description Thesis: Ph. D. in Physical Chemistry, Massachusetts Institute of Technology, Department of Chemistry, 2016.
first_indexed 2024-09-23T16:52:34Z
format Thesis
id mit-1721.1/105045
institution Massachusetts Institute of Technology
language eng
last_indexed 2024-09-23T16:52:34Z
publishDate 2016
publisher Massachusetts Institute of Technology
record_format dspace
spelling mit-1721.1/1050452019-04-11T05:37:34Z Computational Amide I Spectroscopy from the ground up : building and benchmarking new tools to study disordered peptide ensembles Building and benchmarking new tools to study disordered peptide ensembles Reppert, Michael Earl Andrei Tokmakoff. Massachusetts Institute of Technology. Department of Chemistry. Massachusetts Institute of Technology. Department of Chemistry. Chemistry. Thesis: Ph. D. in Physical Chemistry, Massachusetts Institute of Technology, Department of Chemistry, 2016. Cataloged from PDF version of thesis. Includes bibliographical references. In the "form follows function" paradigm of structural biology, we seek to understand-and control-protein function based on our knowledge of protein structure. This process is often difficult for intrinsically disordered proteins and peptides (IDPs) which possess inherent structural disorder in their functional forms. A prototypical example is elastin, a disordered structural protein that provides elastic properties to skin, lungs, and other connective tissues. In such cases, the "form" of the protein must be thought of not as an individual structure, but as a heterogeneous ensemble of structures. The characterization of such ensembles is complicated both by the inherent disorder of the system and by the fact that many common experimental techniques function poorly when applied to IDPs. In this work, we present our recent progress in developing experimental and computational tools for characterizing IDP ensembles using Amide I (backbone carbonyl stretch) vibrational spectroscopy. In this approach, the infrared (IR) absorption frequencies of isotope-labeled amide bonds act as sensitive probes of local electrostatic environment and, ultimately, of local structure. By producing and characterizing experimentally a progression of increasingly complex model systems ranging from dipeptide fragments to isotope-labeled proteins, we develop an efficient and robust spectroscopic model capable of predicting Amide I vibrational frequencies from atomistic protein structures to within a few cm-¹ of error. We apply these methods to the analysis a family of short (eight-residue) elastin-like peptides (ELPs), fragments of the elastin protein, whose local structure is believed to be critical to elastin function. Using our empirically-parameterized frequency maps, we test and refine molecular dynamics ensembles by quantitative comparison against isotope-labeled experimental data. This combination of isotope-labeled IR data, high level spectroscopic modeling, and well-sampled molecular dynamics ensembles provides both local conformational insight into the molecular structures underlying elastic function and a point of departure for testing and refining force-field based structure prediction methods for intrinsically disordered systems. by Michael Earl Reppert. Ph. D. in Physical Chemistry 2016-10-25T19:51:10Z 2016-10-25T19:51:10Z 2016 2016 Thesis http://hdl.handle.net/1721.1/105045 959711382 eng M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission. http://dspace.mit.edu/handle/1721.1/7582 354 pages application/pdf Massachusetts Institute of Technology
spellingShingle Chemistry.
Reppert, Michael Earl
Computational Amide I Spectroscopy from the ground up : building and benchmarking new tools to study disordered peptide ensembles
title Computational Amide I Spectroscopy from the ground up : building and benchmarking new tools to study disordered peptide ensembles
title_full Computational Amide I Spectroscopy from the ground up : building and benchmarking new tools to study disordered peptide ensembles
title_fullStr Computational Amide I Spectroscopy from the ground up : building and benchmarking new tools to study disordered peptide ensembles
title_full_unstemmed Computational Amide I Spectroscopy from the ground up : building and benchmarking new tools to study disordered peptide ensembles
title_short Computational Amide I Spectroscopy from the ground up : building and benchmarking new tools to study disordered peptide ensembles
title_sort computational amide i spectroscopy from the ground up building and benchmarking new tools to study disordered peptide ensembles
topic Chemistry.
url http://hdl.handle.net/1721.1/105045
work_keys_str_mv AT reppertmichaelearl computationalamideispectroscopyfromthegroundupbuildingandbenchmarkingnewtoolstostudydisorderedpeptideensembles
AT reppertmichaelearl buildingandbenchmarkingnewtoolstostudydisorderedpeptideensembles