Deoxyribonucleate (DNA) preparations from Moraxella nonliquefaciens elicited genetic transformation of Neisseria catarrhalis recipient cells, and vice versa. The frequency was low (0·0005% transformation for the most reactive of six strains), as might be expected of an interaction between two organisms as dissimilar as a rod and a coccus. Evidence that the hereditary change (attainment by susceptible cells of resistance to 500 μg. dihydrostreptomycin/ml.) was due to transformation was provided by the typical time course of the reaction, the typical linear response to decreasing concentrations of DNA below 0·1 μg./ml., and by tests of transforming activity of DNA preparations extracted from 11 dihydrostreptomycin-resistant (str-r) strains which arose by intergeneric transformation. These DNAs had relatively high transforming activity for recipient strains of both species. Thus, the str-r region of the transforming DNA molecule from a transformant strain of M. nonliquefaciens was recognized and genetically integrated by populations of N. catarrhalis recipient cells at frequencies as much as 10,000 times higher than those of DNA from strains of M. nonliquefaciens str-r (derived by spontaneous mutation). The results with DNA preparations from particular transformants are interpreted as indicating that the length of a DNA nucleotide sequence which is integrated by a cell during str-r transformation may differ for different cells of the same treated population.
BraccoR. M.,
KraussM. R.,
RoeA. S.,
MacLeodC. M.1957; Transformation reactions between pneumococcus and three strains of streptococci. J. exp. Med. 106:247
CatlinB. W.,
CunninghamL. S.1961; Transforming activities and base contents of deoxyribonucleate preparations from various neisseriae. J. gen. Microbiol. 26:303
CatlinB. W.,
CunninghamL. S.1964a; Genetic transformation of Neisseria catarrhalis by deoxyribonucleate preparations having different average base compositions. J. gen. Microbiol. 37:341
CatlinB. W.,
CunninghamL. S.1964b; Transforming activities and base composition of deoxyribonueleates from strains of Moraxella and Mima. J. gen. Microbiol. 37:353
HotchkissR. D.1957; Criteria for quantitative genetic transformation of bacteria. In The Chemical Basis of Heredity. Ed. by
McElroyW. D.,
GlassB.
Baltimore: The Johns Hopkins Press;
LeidyG.,
HahnE.,
AlexanderH. E.1956; On the specificity of the desoxyribonucleic acid which induces streptomycin resistance in Hemophilus. J. exp. Med. 104:305
MarmurJ.,
SchildkrautC. L.,
DotyP.1961; The reversible denaturation of DNA and its use in studies of nucleic acid homologies and the biological relatedness of microorganisms. J. Chim. phys. p 945
NesterE. W.,
SchaferM.,
LederbergJ.1963; Gene linkage in DNA transfer: a cluster of genes concerned with aromatic biosynthesis in Bacillus subtilis. Genetics 48:529