The interaction of bisbenzimide (Hoechst 33258) with DNA has been studied by microcalorimetry, fluorimetry and fluorescence polarization measurements. The binding does not involve intercalation, takes place in at least two modes and occurs in the major groove at low dye/DNA molar ratio (first mode of binding), in agreement with previous proposals by other Authors. ase in ionic strength. Basically the same type of binding takes place on chromatin, as detected by calorimetry. However, at high dye/DNA molar ratio about 30% of DNA is not accessible to the dye. The decreased accessibility appears to be mainly related to the nucleosomal structure of chromatin.
The interaction of bisbenzimide with DNA.
ALLEGRA, Paola;
1984-01-01
Abstract
The interaction of bisbenzimide (Hoechst 33258) with DNA has been studied by microcalorimetry, fluorimetry and fluorescence polarization measurements. The binding does not involve intercalation, takes place in at least two modes and occurs in the major groove at low dye/DNA molar ratio (first mode of binding), in agreement with previous proposals by other Authors. ase in ionic strength. Basically the same type of binding takes place on chromatin, as detected by calorimetry. However, at high dye/DNA molar ratio about 30% of DNA is not accessible to the dye. The decreased accessibility appears to be mainly related to the nucleosomal structure of chromatin.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.