L. Profils-de-topographie-et-de-phase-sont-indiqués-sur-la-figure and B. , 02 dans le cas de l'ADN directement posé sur la surface terminée amine Pour chaque ligne de l'image, on repère le minimum de la phase, la hauteur de la corde de l'ADN et la phase correspondante au maximum en topographie de l'ADN (cf. figure B.02) On trace sur les figures B.03 et B.04 les deux valeurs de la phase obtenues pour chaque ligne de l'image, en fonction

. Dans-ce-cas, on voit clairement une dépendance entre la phase et la hauteur mesurée (cf. figures B.03 et B.04) On observe le même niveau de dispersion pour les hauteurs que dans le cas de l'ADN sur la surface terminée amine, Cette dépendance est la plus nette entre le minimum de la phase et la hauteur de la corde d'ADN (cf. figure B.03 en b) et B.04 en b))

P. Cette-méthode, ADN en fonction du niveau d'enroulement de la molécule On peut également accéder aux forces mises en jeu. Lorsque la protéine interagit avec l'ADN, la molécule est soit allongée ou compactée. On peut également suivre le niveau d'enroulement de la molécule. On donne sur la figure D.01, l'allure d'une courbe de force

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