Atomic force microscopy studies of Langmuir-Blodgett films of cytochrome P450scc: Hemeprotein aggregation states and interaction with lipids

Tapping mode atomic force microscopy was applied for a study of the molecul ar organization and aggregation states of purified bovine adrenocortical cy tochrome P450scc present in thin solid films. The films of pure cytochrome P450scc or cytochrome P450scc mixed with lipids were transferred onto subst rates of highly oriented pyrolytic graphite or mica. Images of the cytochro me P450scc films show that the topology of the proteins is drastically depe ndent on surface pressure. An effect of hemeprotein on the structural organ ization of lipid was observed. Images of the hemeprotein molecules and/or t heir aggregates provide a new insight for the further understanding of the nature of hemeprotein-hemeprotein and hemeprotein-lipid interactions as wel l as the membrane topology of cytochrome P450scc.