DUGGAN D E, ANDERSON A W, ELLIKER P R
Appl Microbiol. 1963 Sep;11(5):413-7. doi: 10.1128/am.11.5.413-417.1963.
The R(1) strain of Micrococcus radiodurans, previously determined to be more resistant than three other strains exposed to gamma radiation, was studied further to determine the influence of certain environmental factors on resistance to radiation inactivation. The frozen state offered insignificant protection to the organisms irradiated in raw puréed beef. Resistance was reduced by higher menstruum temperatures (40 and 50 C) during irradiation. Preirradiation heat treatment was found to lower resistance to subsequent irradiation. When the cells were irradiated in buffer at pH 5, 7, or 9, no differences in resistance were noted. Cell suspensions in buffer were protected to some extent by cysteine but not by thioglycolate. Ascorbate enhanced radiation inactivation.
耐辐射微球菌的R(1)菌株，先前已确定其比其他三种暴露于伽马辐射的菌株更具抗性，现对其进行了进一步研究，以确定某些环境因素对辐射失活抗性的影响。冷冻状态对生牛肉泥中辐照的微生物提供的保护作用微不足道。照射期间，较高的介质温度（40和50摄氏度）会降低抗性。发现辐照前的热处理会降低对后续辐照的抗性。当细胞在pH值为5、7或9的缓冲液中辐照时，未观察到抗性差异。缓冲液中的细胞悬液在一定程度上受到半胱氨酸的保护，但不受巯基乙酸盐的保护。抗坏血酸会增强辐射失活。
