eprintid: 17241
rev_number: 24
userid: 1419
dir: disk0/00/01/72/41
datestamp: 2013-02-08 21:02:18
lastmod: 2021-06-12 23:55:30
status_changed: 2013-02-08 21:02:18
type: article
metadata_visibility: show
item_issues_count: 0
eprint_status: archive
creators_name: Asciutto, EK
creators_name: General, IJ
creators_name: Xiong, K
creators_name: Asher, SA
creators_name: Madura, JD
creators_email: 
creators_email: 
creators_email: 
creators_email: asher@pitt.edu
creators_email: 
creators_id: 
creators_id: 
creators_id: 
creators_id: ASHER
creators_id: 
title: Sodium perchlorate effects on the helical stability of a mainly alanine peptide
ispublished: pub
divisions: sch_as_chemistry
full_text_status: public
abstract: Sodium perchlorate salt (NaClO4) is commonly used as an internal intensity standard in ultraviolet resonance Raman (UVRR) spectroscopy experiments. It is well known that NaClO4 can have profound effects on peptide stability. The impact of NaClO4 on protein stability in UVRR experiments has not yet been fully investigated. It is well known from experiment that protein stability is strongly affected by the solution composition (water, salts, osmolytes, etc.). Therefore, it is of the utmost importance to understand the physical basis on which the presence of salts and osmolytes in the solution impact protein structure and stability. The aim of this study is to investigate the effects of NaClO4, on the helical stability of an alanine peptide in water. Based upon replica-exchange molecular dynamics data, it was found that NaClO4 solution strongly stabilizes the helical state and that the number of pure helical conformations found at room temperature is greater than in pure water. A thorough investigation of the anion effects on the first and second solvation shells of the peptide, along with the Kirkwood-Buff theory for solutions, allows us to explain the physical mechanisms involved in the observed specific ion effects. A direct mechanism was found in which ClO4 ̄ ions are strongly attracted to the folded backbone. © 2010 by the Biophysical Society.
date: 2010-01-20
date_type: published
publication: Biophysical Journal
volume: 98
number: 2
pagerange: 186 - 196
refereed: TRUE
issn: 0006-3495
id_number: 10.1016/j.bpj.2009.10.013
other_id: NLM PMC2808484
pmcid: PMC2808484
pmid: 20338840
mesh_headings: Alanine--chemistry
mesh_headings: Algorithms
mesh_headings: Circular Dichroism
mesh_headings: Ions--chemistry
mesh_headings: Models, Chemical
mesh_headings: Peptides--chemistry
mesh_headings: Perchloric Acid--chemistry
mesh_headings: Protein Stability
mesh_headings: Protein Structure, Secondary
mesh_headings: Sodium Compounds--chemistry
mesh_headings: Temperature
mesh_headings: Water--chemistry
chemical_names: Ions
chemical_names: Peptides
chemical_names: Sodium Compounds
chemical_names: Alanine
chemical_names: Perchloric Acid
chemical_names: Water
chemical_names: sodium perchlorate
citation:   Asciutto, EK and General, IJ and Xiong, K and Asher, SA and Madura, JD  (2010) Sodium perchlorate effects on the helical stability of a mainly alanine peptide.  Biophysical Journal, 98 (2).  186 - 196.  ISSN 0006-3495     
document_url: http://d-scholarship-dev.library.pitt.edu/17241/1/licence.txt