RT Journal Article SR Electronic(1) A1 Catlin, B. W. A1 Cunningham, L. S.YR 1964 T1 Genetic Transformation of Neisseria catarrhalis by Deoxyribonucleate Preparations having Different Average Base Compositions JF Microbiology, VO 37 IS 3 SP 341 OP 352 DO https://doi.org/10.1099/00221287-37-3-341 PB Microbiology Society, SN 1465-2080, AB The base contents of deoxyribonucleate (DNA) preparations from 7 strains of Neisseria catarrhalis were determined chromatographically. Three non-overlapping classes were distinguished by mole % guanine + cytosine. These centred about the values 41% (2 strains), 42.3% (4 strains, including atcc 8193), and 44·5% (strain nctc 4403), Each of the 7 strains was capable of undergoing genetic transformation. DNA preparations from spontaneous streptomycin-resistant mutants of all 7 strains elicited transformation of recipient strains in all 49 possible combinations. Results with this group, therefore, do not support the hypothesis that success in transferring genetic information between 2 strains requires identity of average DNA base contents. Differences of reciprocal transformation frequencies and of 4 physiological characteristies (nitrate reduction, pigment production on vancomycin-containing agar, hydrolysis of gelatin, and growth at 28°) appeared to separate 6 of the strains of Neisseria catarrhalis from the seventh (nctc 4103), which may properly be named N, cincrea., UL https://www.microbiologyresearch.org/content/journal/micro/10.1099/00221287-37-3-341