Effect of Osmolytes on the Conformational Behavior of a Macromolecule in a Cytoplasm-like Crowded Environment: A Femtosecond Mid-IR Pump-Probe Spectroscopy Study

Achintya Kundu, Pramod Kumar Verma, Minhaeng Cho

Research output: Contribution to journalArticle

5 Citations (Scopus)

Abstract

Osmolytes found endogenously in almost all living beings play an important role in regulating cell volume under harsh environment. Here, to address the longstanding questions about the underlying mechanism of osmolyte effects, we use femtosecond mid-IR pump-probe spectroscopy with two different IR probes that are the OD stretching mode of HDO and the azido stretching mode of azido-derivatized poly(ethylene glycol) dimethyl ether (PEGDME). Our experimental results show that protecting osmolytes bind strongly with water molecules and dehydrate polymer surface, which results in promoting intramolecular interactions of the polymer. By contrast, urea behaves like water molecules without significantly disrupting water H-bonding network and favors extended and random-coil segments of the polymer chain by directly participating in solvation of the polymer. Our findings highlight the importance of direct interaction between urea and macromolecule, while protecting osmolytes indirectly affect the macromolecule through enhancing the water-osmolyte interaction in a crowded environment, which is the case that is often encountered in real biological systems.

Original languageEnglish
Pages (from-to)724-731
Number of pages8
JournalJournal of Physical Chemistry Letters
Volume9
Issue number4
DOIs
Publication statusPublished - 2018 Feb 15

Fingerprint

Macromolecules
Spectrum Analysis
Polymers
Cytoplasm
Pumps
Spectroscopy
Water
Urea
Stretching
Molecules
Solvation
Biological systems
Cell Size
Polyethylene glycols
Ethers
Hydrogen

ASJC Scopus subject areas

  • Materials Science(all)

Cite this

@article{6d3935dd6ba04b86a82bdb6efc7afd82,
title = "Effect of Osmolytes on the Conformational Behavior of a Macromolecule in a Cytoplasm-like Crowded Environment: A Femtosecond Mid-IR Pump-Probe Spectroscopy Study",
abstract = "Osmolytes found endogenously in almost all living beings play an important role in regulating cell volume under harsh environment. Here, to address the longstanding questions about the underlying mechanism of osmolyte effects, we use femtosecond mid-IR pump-probe spectroscopy with two different IR probes that are the OD stretching mode of HDO and the azido stretching mode of azido-derivatized poly(ethylene glycol) dimethyl ether (PEGDME). Our experimental results show that protecting osmolytes bind strongly with water molecules and dehydrate polymer surface, which results in promoting intramolecular interactions of the polymer. By contrast, urea behaves like water molecules without significantly disrupting water H-bonding network and favors extended and random-coil segments of the polymer chain by directly participating in solvation of the polymer. Our findings highlight the importance of direct interaction between urea and macromolecule, while protecting osmolytes indirectly affect the macromolecule through enhancing the water-osmolyte interaction in a crowded environment, which is the case that is often encountered in real biological systems.",
author = "Achintya Kundu and Verma, {Pramod Kumar} and Minhaeng Cho",
year = "2018",
month = "2",
day = "15",
doi = "10.1021/acs.jpclett.7b03297",
language = "English",
volume = "9",
pages = "724--731",
journal = "Journal of Physical Chemistry Letters",
issn = "1948-7185",
publisher = "American Chemical Society",
number = "4",

}

TY - JOUR

T1 - Effect of Osmolytes on the Conformational Behavior of a Macromolecule in a Cytoplasm-like Crowded Environment

T2 - A Femtosecond Mid-IR Pump-Probe Spectroscopy Study

AU - Kundu, Achintya

AU - Verma, Pramod Kumar

AU - Cho, Minhaeng

PY - 2018/2/15

Y1 - 2018/2/15

N2 - Osmolytes found endogenously in almost all living beings play an important role in regulating cell volume under harsh environment. Here, to address the longstanding questions about the underlying mechanism of osmolyte effects, we use femtosecond mid-IR pump-probe spectroscopy with two different IR probes that are the OD stretching mode of HDO and the azido stretching mode of azido-derivatized poly(ethylene glycol) dimethyl ether (PEGDME). Our experimental results show that protecting osmolytes bind strongly with water molecules and dehydrate polymer surface, which results in promoting intramolecular interactions of the polymer. By contrast, urea behaves like water molecules without significantly disrupting water H-bonding network and favors extended and random-coil segments of the polymer chain by directly participating in solvation of the polymer. Our findings highlight the importance of direct interaction between urea and macromolecule, while protecting osmolytes indirectly affect the macromolecule through enhancing the water-osmolyte interaction in a crowded environment, which is the case that is often encountered in real biological systems.

AB - Osmolytes found endogenously in almost all living beings play an important role in regulating cell volume under harsh environment. Here, to address the longstanding questions about the underlying mechanism of osmolyte effects, we use femtosecond mid-IR pump-probe spectroscopy with two different IR probes that are the OD stretching mode of HDO and the azido stretching mode of azido-derivatized poly(ethylene glycol) dimethyl ether (PEGDME). Our experimental results show that protecting osmolytes bind strongly with water molecules and dehydrate polymer surface, which results in promoting intramolecular interactions of the polymer. By contrast, urea behaves like water molecules without significantly disrupting water H-bonding network and favors extended and random-coil segments of the polymer chain by directly participating in solvation of the polymer. Our findings highlight the importance of direct interaction between urea and macromolecule, while protecting osmolytes indirectly affect the macromolecule through enhancing the water-osmolyte interaction in a crowded environment, which is the case that is often encountered in real biological systems.

UR - http://www.scopus.com/inward/record.url?scp=85042208226&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85042208226&partnerID=8YFLogxK

U2 - 10.1021/acs.jpclett.7b03297

DO - 10.1021/acs.jpclett.7b03297

M3 - Article

C2 - 29365266

AN - SCOPUS:85042208226

VL - 9

SP - 724

EP - 731

JO - Journal of Physical Chemistry Letters

JF - Journal of Physical Chemistry Letters

SN - 1948-7185

IS - 4

ER -