| Abstract: | Tobacco nuclear DNA (nDNA) was isolated from tobacco leaf nuclei which were prepared according to our previously published procedure 8]. The nDNA was characterized by base analysis, absorption spectrophotometry, analytical CsCl density gradient equilibrium centrifugation and by its melting behaviour. The results show that the isolated tobacco nDNA is native, high molecular weight DNA, which is free of detectable amounts of chloroplast DNA, RNA, protein and polysaccharides. From its melting behaviour it was concluded that tobacco nDNA can be placed close to calf thymus DNA with respect to intramolecular heterogeneity. Experiments on the partial and complete denaturation of tobacco nDNA and its ability to renature are also reported. |
