Microcalorimetric titrations of whole chromatin and histones with sodium dodecylsulfate were performed at pH 7 and 25 degrees C. Enthalpy variations at low detergent concentration (less than 0.02%) are much more negative for histones than for chromatin. At 0.065% sodium dodecylsulfate the difference between the two curves becomes constant and, after correction for monomerization effects, amounts to +130 kcal/mol of nucleosomal unit. Core particles show heat effects similar to those of histones. These findings suggest that the chromatin structure is not stabilized exclusively by electrostatic interactions and that hydrogen bonds responsible for the additional stability may be contributed by non histone chromatin proteins.
CALORIMETRIC ANALYSIS OF SODIUM DODECYLSULFATE-CHROMATIN INTERACTION / Giartosio, Anna; Ferraro, Anna; Altieri, Fabio; Eufemi, Margherita; Turano, Carlo. - In: PHYSIOLOGICAL CHEMISTRY AND PHYSICS AND MEDICAL NMR. - ISSN 0748-6642. - STAMPA. - 20:1(1988), pp. 55-60.
CALORIMETRIC ANALYSIS OF SODIUM DODECYLSULFATE-CHROMATIN INTERACTION
GIARTOSIO, Anna;FERRARO, Anna;ALTIERI, Fabio;EUFEMI, Margherita;TURANO, Carlo
1988
Abstract
Microcalorimetric titrations of whole chromatin and histones with sodium dodecylsulfate were performed at pH 7 and 25 degrees C. Enthalpy variations at low detergent concentration (less than 0.02%) are much more negative for histones than for chromatin. At 0.065% sodium dodecylsulfate the difference between the two curves becomes constant and, after correction for monomerization effects, amounts to +130 kcal/mol of nucleosomal unit. Core particles show heat effects similar to those of histones. These findings suggest that the chromatin structure is not stabilized exclusively by electrostatic interactions and that hydrogen bonds responsible for the additional stability may be contributed by non histone chromatin proteins.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
