Abstract
Three auxotrophic mutants of Bacillus subtilis were transformed to nutritional independence with deoxyribonucleate (DNA) isolated from a wild type of B. subtilis, strain 23. As little as 2 x 10-4 [mu]g of DNA effects transformation of heat-treated spores allowed to germinate in a glucose-minimal medium. The number of transformants produced is directly related to the quantitity of DNA added and transformation is prevented by treatment with deoxyribonuclease. The specific activity of the donor DNA is increased by removal of protein and it also appears that a ribonucleate fraction, closely associated with donor DNA, enhances transformation activity. An unidentified factor in yeast extract is also required for efficient transformation. The effective DNA is relatively labile to freezing and storage in solutions of low ionic strength, but is relatively stable in 2 [image] NaCl solutions.