Department of Molecular, Microbial and Structural Biology, University of Connecticut Health Center, Farmington, CT 06030-3305, USA.
J Appl Microbiol. 2011 Sep;111(3):663-70. doi: 10.1111/j.1365-2672.2011.05095.x. Epub 2011 Jul 20.
To determine the effects of Mn levels in Bacillus megaterium sporulation and spores on spore resistance.
Bacillus megaterium was sporulated with no added MnCl(2) and up to 1 mmol l(-1) MnCl(2). The resultant spores were purified and loosely bound Mn removed, and spore Mn levels were found to vary c. 100-fold. The Mn level had no effect on spore γ-radiation resistance, but B. megaterium spores with elevated Mn levels had higher resistance to UVC radiation (as did Bacillus subtilis spores), wet and dry heat and H(2)O(2). However, levels of dipicolinic acid and the DNA-protective α/β-type small, acid-soluble spore proteins were the same in spores with high and low Mn levels.
Mn levels either in sporulation or in spores are important factors in determining levels of B. megaterium spore resistance to many agents, with the exception of γ-radiation.
The Mn level in sporulation is an important factor to consider when resistance properties of B. megaterium spores are examined, and will influence the UV resistance of B. subtilis spores, some of which are used as biological dosimeters.
确定芽孢杆菌形成芽孢过程中锰水平以及芽孢内锰含量对芽孢抗性的影响。
用未添加 MnCl2 和高达 1mmol/L MnCl2 的方法使芽孢杆菌形成芽孢。然后对得到的芽孢进行纯化并去除松散结合的锰，发现芽孢内的锰含量变化约 100 倍。锰含量对芽孢的γ射线抗性没有影响，但高含锰水平的芽孢杆菌的芽孢对 UVC 辐射（枯草芽孢杆菌的芽孢也是如此）、湿热和干热以及 H2O2 的抗性更高。然而，高含锰和低含锰水平的芽孢中的二吡啶羧酸和 DNA 保护α/β 型小、酸溶性芽孢蛋白的水平相同。
无论是在形成芽孢过程中还是在芽孢内，锰含量都是决定芽孢杆菌抵抗多种试剂能力的重要因素，γ 射线除外。
在研究芽孢杆菌芽孢的抗性特性时，芽孢形成过程中的锰含量是一个重要的考虑因素，并且会影响枯草芽孢杆菌孢子的紫外线抗性，其中一些孢子被用作生物剂量计。
