lambda-DNA Hind III was denatured by HCl, renatured by NaOH, and digested by DNase I sequentially. The produced mixture was separated with Sephadex G200 column, and the chromatograph showed a very weak peak of one com...lambda-DNA Hind III was denatured by HCl, renatured by NaOH, and digested by DNase I sequentially. The produced mixture was separated with Sephadex G200 column, and the chromatograph showed a very weak peak of one component resistant to the digestion of DNase I. The results of AFM studies on this component indicated that an unusual form of DNA was present, with the height 13 times that of double-stranded DNA. By comparison with known results, it is suggested that this is a multi-stranded DNA other than simple supercoils.展开更多
THE intra- and intermolecular forces of DNA are essential to understanding its structure andfunctional behavior. However, direct measurement of interaction forces requires that the stateof a system be monitored simult...THE intra- and intermolecular forces of DNA are essential to understanding its structure andfunctional behavior. However, direct measurement of interaction forces requires that the stateof a system be monitored simultaneously while an independent force is applied. Until now, on-ly X-ray crystallography, light scattering, and nuclear magnetic resonance spectroscopy havebeen used to measure these molecular forces using indirect physical and thermodynamic meth-展开更多
文摘lambda-DNA Hind III was denatured by HCl, renatured by NaOH, and digested by DNase I sequentially. The produced mixture was separated with Sephadex G200 column, and the chromatograph showed a very weak peak of one component resistant to the digestion of DNase I. The results of AFM studies on this component indicated that an unusual form of DNA was present, with the height 13 times that of double-stranded DNA. By comparison with known results, it is suggested that this is a multi-stranded DNA other than simple supercoils.
基金This project was supported by the Grant of Chinese Academy of Sciences (KJ951-A1-502) the National Natural Science Foundation of China (19634010)
文摘THE intra- and intermolecular forces of DNA are essential to understanding its structure andfunctional behavior. However, direct measurement of interaction forces requires that the stateof a system be monitored simultaneously while an independent force is applied. Until now, on-ly X-ray crystallography, light scattering, and nuclear magnetic resonance spectroscopy havebeen used to measure these molecular forces using indirect physical and thermodynamic meth-
