Multifactorial resistance of Bacillus subtilis spores to low-pressure plasma sterilization

作者：Erika Muratov, Florian P. Rosenbaum, Felix M. Fuchs, Nikea J. Ulrich, Peter Awakowicz, Peter Setlow, Ralf Moeller · 发表于：Applied and Environmental Microbiology · 年份：2023 · DOI：10.1128/aem.01329-23 · 被引用次数：9 · 研究领域：Plasma Applications and Diagnostics、Microbial Inactivation Methods、Polyamine Metabolism and Applications

ABSTRACT Common sterilization techniques for labile and sensitive materials have far-reaching applications in medical, pharmaceutical, and industrial fields. Heat inactivation, chemical treatment, and radiation are established methods to inactivate microorganisms, but pose a threat to humans and the environment and can damage susceptible materials or products. Recent studies have demonstrated that cold low-pressure plasma (LPP) treatment is an efficient alternative to common sterilization methods, as LPP’s levels of radicals, ions, (V)UV-radiation, and exposure to an electromagnetic field can be modulated using different process gases, such as oxygen, nitrogen, argon, or synthetic (ambient) air. To further investigate the effects of LPP, spores of the Gram-positive model organism Bacillus subtilis were tested for their LPP susceptibility including wild-type spores and isogenic spores lacking DNA-repair mechanisms such as non-homologous end-joining (NHEJ) or abasic endonucleases, and protective proteins like α/β-type small acid-soluble spore proteins (SASP), coat proteins, and catalase. These studies aimed to learn how spores resist LPP damage by examining the roles of key spore proteins and DNA-repair mechanisms. As expected, LPP treatment decreased spore survival, and survival after potential DNA damage generated by LPP involved efficient DNA repair following spore germination, spore DNA protection by α/β-type SASP, and catalase breakdown of hydrogen peroxide that can genera...