Tertiary structures of the Escherichia coli and human chromosome 21 molecules of DNA

DNA in phosphorus atom representation: the heteronomous double helices of poly(dA).poly(dT) and poly(dG).poly(dC) and simulation of the yeast genome and of a human chromosome DNA

We extracted phosphorus atom coordinates from the database of DNA crystal structures and calculated geometrical parameters needed to reproduce the crystal structures in the phosphorus atom representation. Using the geometrical parameters we wrote a piece of software assigning the phosphorus atom coordinates to the DNA of any nucleotide sequence. The software demonstrates non-negligible influence of the primary structure on DNA helicity, which may stand behind the heteromonous double helices of poly(dA).poly(dT) and poly(dG).poly(dC). In addition, the software is so simple that it makes possible to simulate the "crystal" structures of not only viral DNAs, but also the whole genome of Saccharomyces cerevisiae as well as the DNA human chromosome 22 having dozens of megabases in length.