1. Role of DNA repair in Bacillus subtilis spore resistance to high energy and low energy electron beam treatments
- Author
-
Georgios Akepsimaidis, Yifan Zhang, Ralf Moeller, Nina Huber, Jörg Stülke, Barbora Dubovcova, Nicolas Meneses, David Drissner, and Alexander Mathys
- Subjects
DNA, Bacterial ,High energy electron beam ,DNA repair ,DNA damage ,Mutant ,Electrons ,Bacillus subtilis ,Microbiology ,Endospore ,03 medical and health sciences ,chemistry.chemical_compound ,Bacterial Proteins ,Inactivation mechanism ,Bacterial spores ,030304 developmental biology ,Spores, Bacterial ,0303 health sciences ,Microbial Viability ,biology ,030306 microbiology ,Chemistry ,Low energy electron beam ,fungi ,Wild type ,biology.organism_classification ,Cell biology ,Mutation ,Homologous recombination ,DNA ,Food Science - Abstract
Bacillus subtilis spore inactivation mechanisms under low energy electron beam (LEEB) and high energy electron beam (HEEB) treatment were investigated using seven mutants lacking specific DNA repair mechanisms. The results showed that most of the DNA repair-deficient mutants, including ΔrecA, ΔKu ΔligD, Δexo Δnfo, ΔuvrAB and ΔsbcDC, had reduced resistances towards electron beam (EB) treatments at all investigated energy levels (80 keV, 200 keV and 10 MeV) compared to their wild type. This result suggested DNA damage was induced during EB treatments. The mutant lacking recA showed the lowest resistance, followed by the mutant lacking Ku and ligD. These findings indicated that recA, Ku and ligD and their associated DNA repair mechanisms, namely, homologous recombination and non-homologous end joining, play important roles in spore survival under EB treatment. Furthermore, exoA, nfo, uvrAB, splB, polY1 and polY2, which are involved in nucleotide damage repair/removal, showed different levels of effects on spore resistance under EB treatment. Finally, the results suggested that HEEB and LEEB inactivate B. subtilis spores through similar mechanisms. This research will provide a better understanding of how EB technologies inactivate B. subtilis spores and will contribute to the application of these technologies as a non-thermal, gentle spore control approach., Food Microbiology, 87, ISSN:0740-0020, ISSN:1095-9998
- Published
- 2020