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Title: Differential sensitivity of Chironomus and human hemoglobin to gamma radiation

Abstract

Chironomus ramosus is known to tolerate high doses of gamma radiation exposure. Larvae of this insect possess more than 95% of hemoglobin (Hb) in its circulatory hemolymph. This is a comparative study to see effect of gamma radiation on Hb of Chironomus and humans, two evolutionarily diverse organisms one having extracellular and the other intracellular Hb respectively. Stability and integrity of Chironomus and human Hb to gamma radiation was compared using biophysical techniques like Dynamic Light Scattering (DLS), UV-visible spectroscopy, fluorescence spectrometry and CD spectroscopy after exposure of whole larvae, larval hemolymph, human peripheral blood, purified Chironomus and human Hb. Sequence- and structure-based bioinformatics methods were used to analyze the sequence and structural similarities or differences in the heme pockets of respective Hbs. Resistivity of Chironomus Hb to gamma radiation is remarkably higher than human Hb. Human Hb exhibited loss of heme iron at a relatively low dose of gamma radiation exposure as compared to Chironomus Hb. Unlike human Hb, the heme pocket of Chironomus Hb is rich in aromatic amino acids. Higher hydophobicity around heme pocket confers stability of Chironomus Hb compared to human Hb. Previously reported gamma radiation tolerance of Chironomus can be largely attributed to its evolutionarilymore » ancient form of extracellular Hb as evident from the present study. -- Highlights: •Comparison of radiation tolerant Chironomus Hb and radiation sensitive Human Hb. •Amino acid composition of midge and human heme confer differential hydrophobicity. •Heme pocket of evolutionarily ancient midge Hb provide gamma radiation resistivity.« less

Authors:
 [1];  [2];  [3]; ;  [4];  [5];  [1]
  1. Stress Biology Research Laboratory, Department of Zoology, Savitribai Phule University, Pune, 411007 (India)
  2. (India)
  3. Solid State Physics Division, Bhabha Atomic Research Centre, Trombay, Mumbai, 400085 (India)
  4. Bioinformatics Center, Savitribai Phule Pune University, Pune, 411007 (India)
  5. Molecular Biology Division, Bhabha Atomic Research Centre, Trombay, Mumbai, 400085 (India)
Publication Date:
OSTI Identifier:
22598792
Resource Type:
Journal Article
Resource Relation:
Journal Name: Biochemical and Biophysical Research Communications; Journal Volume: 476; Journal Issue: 4; Other Information: Copyright (c) 2016 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; AMINO ACIDS; BLOOD; FLUORESCENCE; FLUORESCENCE SPECTROSCOPY; GAMMA RADIATION; HEME; HEMOGLOBIN; LARVAE; RADIATION DOSES; RADIOSENSITIVITY

Citation Formats

Gaikwad, Pallavi S., Molecular Biology Division, Bhabha Atomic Research Centre, Trombay, Mumbai, 400085, Panicker, Lata, Mohole, Madhura, Sawant, Sangeeta, Mukhopadhyaya, Rita, and Nath, Bimalendu B., E-mail: bbnath@gmail.com. Differential sensitivity of Chironomus and human hemoglobin to gamma radiation. United States: N. p., 2016. Web. doi:10.1016/J.BBRC.2016.05.129.
Gaikwad, Pallavi S., Molecular Biology Division, Bhabha Atomic Research Centre, Trombay, Mumbai, 400085, Panicker, Lata, Mohole, Madhura, Sawant, Sangeeta, Mukhopadhyaya, Rita, & Nath, Bimalendu B., E-mail: bbnath@gmail.com. Differential sensitivity of Chironomus and human hemoglobin to gamma radiation. United States. doi:10.1016/J.BBRC.2016.05.129.
Gaikwad, Pallavi S., Molecular Biology Division, Bhabha Atomic Research Centre, Trombay, Mumbai, 400085, Panicker, Lata, Mohole, Madhura, Sawant, Sangeeta, Mukhopadhyaya, Rita, and Nath, Bimalendu B., E-mail: bbnath@gmail.com. 2016. "Differential sensitivity of Chironomus and human hemoglobin to gamma radiation". United States. doi:10.1016/J.BBRC.2016.05.129.
@article{osti_22598792,
title = {Differential sensitivity of Chironomus and human hemoglobin to gamma radiation},
author = {Gaikwad, Pallavi S. and Molecular Biology Division, Bhabha Atomic Research Centre, Trombay, Mumbai, 400085 and Panicker, Lata and Mohole, Madhura and Sawant, Sangeeta and Mukhopadhyaya, Rita and Nath, Bimalendu B., E-mail: bbnath@gmail.com},
abstractNote = {Chironomus ramosus is known to tolerate high doses of gamma radiation exposure. Larvae of this insect possess more than 95% of hemoglobin (Hb) in its circulatory hemolymph. This is a comparative study to see effect of gamma radiation on Hb of Chironomus and humans, two evolutionarily diverse organisms one having extracellular and the other intracellular Hb respectively. Stability and integrity of Chironomus and human Hb to gamma radiation was compared using biophysical techniques like Dynamic Light Scattering (DLS), UV-visible spectroscopy, fluorescence spectrometry and CD spectroscopy after exposure of whole larvae, larval hemolymph, human peripheral blood, purified Chironomus and human Hb. Sequence- and structure-based bioinformatics methods were used to analyze the sequence and structural similarities or differences in the heme pockets of respective Hbs. Resistivity of Chironomus Hb to gamma radiation is remarkably higher than human Hb. Human Hb exhibited loss of heme iron at a relatively low dose of gamma radiation exposure as compared to Chironomus Hb. Unlike human Hb, the heme pocket of Chironomus Hb is rich in aromatic amino acids. Higher hydophobicity around heme pocket confers stability of Chironomus Hb compared to human Hb. Previously reported gamma radiation tolerance of Chironomus can be largely attributed to its evolutionarily ancient form of extracellular Hb as evident from the present study. -- Highlights: •Comparison of radiation tolerant Chironomus Hb and radiation sensitive Human Hb. •Amino acid composition of midge and human heme confer differential hydrophobicity. •Heme pocket of evolutionarily ancient midge Hb provide gamma radiation resistivity.},
doi = {10.1016/J.BBRC.2016.05.129},
journal = {Biochemical and Biophysical Research Communications},
number = 4,
volume = 476,
place = {United States},
year = 2016,
month = 8
}
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