Analysis of microdensitometric data in terms of probability of cleavage of DNA.
Computer-aided analysis of autoradiographic films of DNA fragments is presented. The Powell least-squares procedure is used for optimization of parameters for components of complex densitometric curves. Since each densitometric spectrum may be divided for several non-overlapped blocks of bands, there is no upper limit on the number of parameters which must be optimized. Eight shapes for the component bands are utilized: symmetric and asymmetric Gauss and Cauchy functions, direct, symmetric and asymmetric product of Gauss function and inverse of Cauchy function, and log-normal function. The probability of DNA cleavage is calculated with correction for multiple cuts. The methods presented was applied to detailed analysis of densitometric spectra of a 21-bp DNA restriction fragment and allowed for direct correlation between structural microheterogeneity of DNA and the resulting cutting pattern. This method should facilitate the analysis of densitometric data from antibiotic-induced cleavage of DNA and footprinting experiments.
Galat
A
A
Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115.
Goldberg
I H
IH
D015502:Absorptiometry, Photon / Q000379:methods*; D001345:Autoradiography; D001483:Base Sequence; D004247:DNA; D004262:DNA Restriction Enzymes; D008432:Mathematical Computing; D011336:Probability; D009353:Zinostatin
D004247:DNA; D009353:Zinostatin; D004262:DNA Restriction Enzymes