How radiation kills cells: survival of Deinococcus radiodurans and Shewanella oneidensis under oxidative stress.
We have recently shown that Deinococcus radiodurans and other radiation resistant bacteria accumulate exceptionally high intracellular manganese and low iron levels. In comparison, the dissimilatory metal-reducing bacterium Shewanella oneidensis accumulates Fe but not Mn and is extremely sensitive to radiation. We have proposed that for Fe-rich, Mn-poor cells killed at radiation doses which cause very little DNA damage, cell death might be induced by the release of Fe(II) from proteins during irradiation, leading to additional cellular damage by Fe(II)-dependent oxidative stress. In contrast, Mn(II) ions concentrated in D. radiodurans might serve as antioxidants that reinforce enzymic systems which defend against oxidative stress during recovery. We extend our hypothesis here to include consideration of respiration, tricarboxylic acid cycle activity, peptide transport and metal reduction, which together with Mn(II) transport represent potential new targets to control recovery from radiation injury.
Ghosal
Debabrota
D
Uniformed Services University of the Health Sciences, Bethesda, MD 20814, USA.
Omelchenko
Marina V
MV
Gaidamakova
Elena K
EK
Matrosova
Vera Y
VY
Vasilenko
Alexander
A
Venkateswaran
Amudhan
A
Zhai
Min
M
Kostandarithes
Heather M
HM
Brim
Hassan
H
Makarova
Kira S
KS
Wackett
Lawrence P
LP
Fredrickson
James K
JK
Daly
Michael J
MJ
D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D034301:Deinococcus / Q000254:growth & development* / Q000502:physiology / Q000528:radiation effects*; D007501:Iron / Q000378:metabolism; D008345:Manganese / Q000378:metabolism; D018384:Oxidative Stress; D011836:Radiation Tolerance; D011839:Radiation, Ionizing; D020592:Shewanella / Q000254:growth & development* / Q000502:physiology / Q000528:radiation effects*; D014466:Ultraviolet Rays
D001426:Bacterial Proteins; D008345:Manganese; D007501:Iron