Interaction of colchicine with DNA molecules.
Colchicine (7.5 X 10-6M or 3.3 X 10-5M) was incubated at pH 7.0, 10.0, or 12.0 with high-molecular DNA from salmon sperm (7 X 10-5M or 3.5 X 10-5M DNA-P) at 40 degrees C. Interaction was monitored by UV spectrophotometry; Amax/Amin ratios, difference and additive spectra, and the quantity of colchicine bound to DNA were presented as functions of time, ionic strength and DNA concentration. Using NMR techniques, delta deltav 1/2/deltac values, chemical shifts and half-line widths of colchicine protons were analyzed as a function of the DNA/colchicine ratio, thus proving the interaction between alkaloid and DNA. An intercalation of the tropolone moiety of colchicine between the nitrogenous bases of DNA is suggested.
Interaction of colchicine with DNA molecules. Colchicine (7.5 X 10-6M or 3.3 X 10-5M) was incubated at pH 7.0, 10.0, or 12.0 with high-molecular DNA from salmon sperm (7 X 10-5M or 3.5 X 10-5M DNA-P) at 40 degrees C. Interaction was monitored by UV spectrophotometry; Amax/Amin ratios, difference and additive spectra, and the quantity of colchicine bound to DNA were presented as functions of time, ionic strength and DNA concentration. Using NMR techniques, delta deltav 1/2/deltac values, chemical shifts and half-line widths of colchicine protons were analyzed as a function of the DNA/colchicine ratio, thus proving the interaction between alkaloid and DNA. An intercalation of the tropolone moiety of colchicine between the nitrogenous bases of DNA is suggested.