Radiation activation of respiration inBacillus cereus T spores

The effects of gamma-irradiation on glucose oxidase activity were studied inBacillus cereus T spores. Radiation was found to activate oxidase in native spores. This activation was greatly enhanced when irradiated spores were subsequently heat-activated. Although activation by heat alone was 1.6 times that by radiation alone, the combined treatment with both radiation and heating resulted in a 12-fold enhancement of oxidase activity over that obtainable by optimum heat activation. Activation by combined treatment of gamma-rays and heat depended on the presence of exchangeable calcium during heating but not during irradiation.