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Updated: Jun 8, 2026
12:07
Profiling Thiol Redox Proteome Using Isotope Tagging Mass Spectrometry
Published on: March 24, 2012
Small-molecule antioxidant proteome-shields in Deinococcus radiodurans
Michael J Daly1, Elena K Gaidamakova, Vera Y Matrosova
1Department of Pathology, Uniformed Services University of the Health Sciences, Bethesda, Maryland, United States of America. mdaly@usuhs.edu
Plos One
|September 15, 2010
Summary
Extremely radiation-resistant bacteria like Deinococcus radiodurans use manganese-metabolite complexes to protect proteins from radiation damage. These complexes shield cellular components from oxidative stress, offering a new avenue for radioprotection strategies.
Area of Science:
- Microbiology
- Biochemistry
- Radiation Biology
Background:
- Extremely radiation-resistant bacteria possess unique mechanisms for surviving high doses of ionizing radiation.
- Manganese accumulation and protein protection are linked to radiation resistance in Deinococcus radiodurans.
Purpose of the Study:
- To elucidate the mechanistic link between manganese accumulation, protein protection, and extreme radiation resistance in Deinococcus radiodurans.
- To investigate the protective role of D. radiodurans cell extracts against ionizing radiation-induced protein oxidation.
Main Methods:
- Ultrafiltration of Deinococcus radiodurans cell extracts to obtain protein-free preparations.
- In vitro reconstitution of protective components (manganese, peptides, phosphate) and enzyme activity assays.
- Ex vivo application of ultrafiltrates to protect Escherichia coli and human Jurkat T cells from ionizing radiation.
Main Results:
- Protein-free ultrafiltrates from D. radiodurans protected proteins from oxidation at massive radiation doses, unlike those from sensitive bacteria.
- D. radiodurans ultrafiltrates contained manganese, phosphate, nucleosides, bases, and peptides.
- Reconstituted Mn(2+)-metabolite complexes preserved enzyme activity under extreme radiation (50,000 Gy), while DNA was obliterated.
- Ex vivo application protected bacterial and human cells from radiation-induced damage.
Conclusions:
- Manganese-metabolite complexes in Deinococcus radiodurans specifically protect proteins against indirect gamma-ray damage.
- These findings suggest a novel approach for radioprotection and highlight the role of manganese in combating reactive oxygen species.
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