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Title: Molten globule state of tear lipocalin: ANS binding restores tertiary interactions

Abstract

Tear lipocalin (TL) may stabilize the lipid layer of tears through a molten globule state triggered by low pH. EPR spectroscopy with site-directed spin labeling, revealed the side chain mobility of residues on the G-strand of TL in a molten globule state; the G-strand retains {beta}-sheet structure. All of the side chains of G-strand residues become more loosely packed, especially residues 96-99. In contrast, the highly mobile side chain of residue 95 on the F-G loop, becomes tightly packed. ANS binding to TL in a molten globule state reestablishes tight packing around side chains that are oriented both inside and outside of the barrel. Unlike RBP and BLG; TL has no disulfide bond between G- and H-strands. It is likely that the central {beta}-sheet in the molten globule state of lipocalins is stabilized by its interactions with the main {alpha}-helix, rather than the interstrand disulfide bond.

Authors:
 [1];  [1];  [2]
  1. Departments of Pathology and Ophthalmology, UCLA School of Medicine, Jules Stein Eye Institute, 100 Stein Plaza, Los Angeles, CA 90095 (United States)
  2. Departments of Pathology and Ophthalmology, UCLA School of Medicine, Jules Stein Eye Institute, 100 Stein Plaza, Los Angeles, CA 90095 (United States). E-mail: bglasgow@mednet.ucla.edu
Publication Date:
OSTI Identifier:
20991369
Resource Type:
Journal Article
Resource Relation:
Journal Name: Biochemical and Biophysical Research Communications; Journal Volume: 357; Journal Issue: 2; Other Information: DOI: 10.1016/j.bbrc.2007.03.186; PII: S0006-291X(07)00678-X; Copyright (c) 2007 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
60 APPLIED LIFE SCIENCES; DISULFIDES; ELECTRON SPIN RESONANCE; LABELLING; LIPIDS; MOBILITY; PH VALUE; PROTEINS; SPECTROSCOPY; VITAMIN A

Citation Formats

Gasymov, Oktay K., Abduragimov, Adil R., and Glasgow, Ben J. Molten globule state of tear lipocalin: ANS binding restores tertiary interactions. United States: N. p., 2007. Web. doi:10.1016/j.bbrc.2007.03.186.
Gasymov, Oktay K., Abduragimov, Adil R., & Glasgow, Ben J. Molten globule state of tear lipocalin: ANS binding restores tertiary interactions. United States. doi:10.1016/j.bbrc.2007.03.186.
Gasymov, Oktay K., Abduragimov, Adil R., and Glasgow, Ben J. Fri . "Molten globule state of tear lipocalin: ANS binding restores tertiary interactions". United States. doi:10.1016/j.bbrc.2007.03.186.
@article{osti_20991369,
title = {Molten globule state of tear lipocalin: ANS binding restores tertiary interactions},
author = {Gasymov, Oktay K. and Abduragimov, Adil R. and Glasgow, Ben J.},
abstractNote = {Tear lipocalin (TL) may stabilize the lipid layer of tears through a molten globule state triggered by low pH. EPR spectroscopy with site-directed spin labeling, revealed the side chain mobility of residues on the G-strand of TL in a molten globule state; the G-strand retains {beta}-sheet structure. All of the side chains of G-strand residues become more loosely packed, especially residues 96-99. In contrast, the highly mobile side chain of residue 95 on the F-G loop, becomes tightly packed. ANS binding to TL in a molten globule state reestablishes tight packing around side chains that are oriented both inside and outside of the barrel. Unlike RBP and BLG; TL has no disulfide bond between G- and H-strands. It is likely that the central {beta}-sheet in the molten globule state of lipocalins is stabilized by its interactions with the main {alpha}-helix, rather than the interstrand disulfide bond.},
doi = {10.1016/j.bbrc.2007.03.186},
journal = {Biochemical and Biophysical Research Communications},
number = 2,
volume = 357,
place = {United States},
year = {Fri Jun 01 00:00:00 EDT 2007},
month = {Fri Jun 01 00:00:00 EDT 2007}
}
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