Action spectra for survival and spore photoproduct formation of Bacillus subtilis irradiated with short-wavelength (200-300 nm) UV at atmospheric pressure and in vacuo.
Action spectra for survival and spore photoproduct formation of Bacillus subtilis irradiated with short-wavelength (200-300 nm) UV at atmospheric pressure and in vacuo.
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DOI：
10.1016/1011-1344(91)80269-n
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发表时间：
1991-10
期刊：
影响因子：
--
通讯作者：
C. Lindberg;G. Horneck
中科院分区：
文献类型：
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作者：
C. Lindberg;G. Horneck
枯草芽孢杆菌的孢子在真空中经受紫外线照射的可能性比在大气条件下低大约十倍。研究了在超高真空（UHV）条件下照射的孢子和在大气压下照射的孢子中的光产物形成。除了“孢子光产物”5-胸腺嘧啶基-5，6-二氢胸腺嘧啶（TDHT）在大气压下受辐射时产生外，在真空中受辐射时还产生另外两种光产物，称为胸腺嘧啶二聚体的顺式和反式异构体。与大气条件相比，在真空条件下孢子中光产物形成的光谱效率降低2-6倍，这取决于波长。由于真空辐照后TDHT的形成并不增加，因此TDHT不能对观察到的真空效应负责。真空特异性光产物可引起孢子对UV光和UHV的同时作用的协同响应。提高量子效率，破坏修复系统和形成不可修复的损伤被假定为B的敏感性增强。枯草芽孢杆菌孢子在真空中紫外线辐射。
Spores ofBacillus subtilisare approximately ten times less likely to survive UV light irradiation in a vacuum than under atmospheric conditions. Photoproduct formation was studied in spores irradiated under ultrahigh vacuum (UHV) conditions and in spores irradiated at atmospheric pressure. In addition to the “spore photoproduct” 5-thyminyl-5,6-dihydrothymine (TDHT), which is produced in response to irradiation at atmospheric pressure, two additional photoproducts, known as the cis—syn and trans—syn isomers of thymine dimer, are produced on irradiationin vacuo. The spectral efficiencies for photoproduct formation in spores are reduced under vacuum conditions compared with atmospheric conditions by a factor of 2–6, depending on the wavelength. Because formation of TDHT does not increase after irradiationin vacuo, TDHT cannot be responsible for the observed vacuum effect. Vacuum specific photoproducts may cause a synergistic response of spores to the simultaneous action of UV light and UHV. An increased quantum efficiency, destruction of repair systems and formation of irreparable lesions are postulated for the enhanced sensitivity ofB. subtilisspores to UV radiationin vacuo.