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.
German Aerospace Center, Institute of Aerospace Medicine, Radiation Biology Division, Department of Photo- and Exobiology, Cologne, Germany. ralf.moeller@dlr.de
Ralf
R
Moeller
Peter
P
Setlow
Gerda
G
Horneck
Thomas
T
Berger
Günther
G
Reitz
Petra
P
Rettberg
Aidan J
AJ
Doherty
Ryuichi
R
Okayasu
Wayne L
WL
Nicholson
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