Roles of the major, small, acid-soluble spore proteins and spore-specific and universal DNA repair mechanisms in resistance of Bacillus subtilis spores to ionizing radiation from X rays and high-energy charged-particle bombardment.
The role of DNA repair by nonhomologous end joining (NHEJ), homologous recombination, spore photoproduct lyase, and DNA polymerase I and genome protection via alpha/beta-type small, acid-soluble spore proteins (SASP) in Bacillus subtilis spore resistance to accelerated heavy ions (high-energy charged [HZE] particles) and X rays has been studied. Spores deficient in NHEJ and alpha/beta-type SASP were significantly more sensitive to HZE particle bombardment and X-ray irradiation than were the recA, polA, and splB mutant and wild-type spores, indicating that NHEJ provides an efficient DNA double-strand break repair pathway during spore germination and that the loss of the alpha/beta-type SASP leads to a significant radiosensitivity to ionizing radiation, suggesting the essential function of these spore proteins as protectants of spore DNA against ionizing radiation.
Moeller
Ralf
R
German Aerospace Center, Institute of Aerospace Medicine, Radiation Biology Division, Department of Photo- and Exobiology, Cologne, Germany. ralf.moeller@dlr.de
Setlow
Peter
P
Horneck
Gerda
G
Berger
Thomas
T
Reitz
Günther
G
Rettberg
Petra
P
Doherty
Aidan J
AJ
Okayasu
Ryuichi
R
Nicholson
Wayne L
WL
D001412:Bacillus subtilis / Q000254:growth & development / Q000502:physiology / Q000528:radiation effects*; D001426:Bacterial Proteins / Q000378:metabolism*; D003359:Cosmic Radiation; D004256:DNA Polymerase I / Q000378:metabolism; D004260:DNA Repair; D011506:Proteins / Q000378:metabolism; D011836:Radiation Tolerance; D011839:Radiation, Ionizing; D011995:Recombination, Genetic; D013171:Spores, Bacterial / Q000502:physiology / Q000528:radiation effects*; D014965:X-Rays
D001426:Bacterial Proteins; D011506:Proteins; C030069:spore-specific proteins, Bacillus; D004256:DNA Polymerase I; C088014:spore photoproduct lyase