Abstract: | The enzyme nucleosidase (EC. 3.2.2.1.) is present in the intact spores, germinated spores as well as vegetative cells of T. In the intact spores the enzymeis resistant to heat and, in fact, has a high temperature optimum. Though the spores themselvesbecome sensitive to heat on germination, the enzyme retains its resistance to heat on germination as well as its high temperature optimum. The vegetative cell enzyme is sensitive to heat. The enzyme in all types of cells &; spores is resistant to octyl alcohol. There is a close correlation between the development of heat resistance in the sporulating cells and that of heat resistance of the enzyme. |