Recently X-ray diffraction provided the structure of nucleosomes. External disturbances can unwrap DNA from the histone-protein and their genetic information becomes readable. This is strongly connected with cancer initiation. Therefore, first we performed charge transfer (CT) calculations between polythymidine and a periodic model-protein chain with a lysine or arginine and three glycines. The CT calculations were repeated between the infinite chains using combined solid state physical and quantum chemical methods. We found that the CT between the unit cells of an infinite polythymidine and poly(lysine-triglycine) is 0.04 e and 0.03 e for poly(arginine-triglycine). We investigated the influence of the basis set quality on the calculated CT values using a molecular model built of a thymidine and lysine or arginine. We have calculated also the bands of polythymidine and the two protein model chains. We have found that the differences between the highest level of the valence band of single polythymidine chain and the lowest level of the conduction bands of the model protein chains (6-11 eV depending on the basis set) are too large to assume a direct CT between these two bands.
- Band structure of poly[Arg-triglycine]
- Band structure of poly[Lys-triglycine]
- Charge transfer between PO-Arg
- Charge transfer between PO-Lys
- Nucleosome structure
ASJC Scopus subject areas
- Physical and Theoretical Chemistry