Mitochondrial DNA I. Preparation and properties of mitochondrial DNA from chick liver

摘要: Abstract 1. A convenient procedure for the large-scale preparation of mitochondria from chick liver is described, which suitable mitochondrial DNA. 2. For extraction DNA, were preincubated with deoxyribonuclease (EC 3.1.4.5) and lysed in 0.15 M NaCl, 0.1 sodium EDTA (pH 9.0) 2 % dodecyl sulfate. After deproteinization 1 NaClO4 chloroform, treatment ribonuclease 2.7.7.16) DNA was purified by chromatography on a column methylated albumin adsorbed kieselguhr. The maximal yield 0.2 μg high molecular weight ( s 20,w ≧ 24 S ) per mg protein. 3. Mitochondrial prepared this has an equilibrium density CsCl 1.708 g/cm3 (nuclear 1.701 g/cm3); it melts sharply Tm 90.0° 0.015 citrate, pH 7.0 87.5°). alkaline denaturation increased 0.018 g/cm3. 4. Under optimal conditions, rapid renaturation denatured shown to occur both band shift gradient spectrophotometric hypochromicity measurements at 260 mμ. Renaturation followed second-order kinetics proves that due homogeneity base sequence not inability complementary strands completely separate under denaturing conditions. 5. constant compared constants reported others bacterial viral DNA's standard It rate good agreement our earlier suggestion total genetic information population contained double-stranded molecule 10·106–11·106.