Question

In the 1950s, the race to solve the secondary structure of dna became intense. in an uncharacteristic rush to publish, linus pauling erroneously proposed a triple-stranded structure in february 1953. this model had the nitrogenous bases on the exterior and the sugar−phosphate backbones clustered in the middle. how does the orientation of the sugar−phosphate backbone in this model compare with the one proposed by watson and crick? do you think pauling's structure could exist in cells? why or why not?

Answer 1

The Watson-Crick model has the sugar-phosphate backbone on the outside of the double helix of DNA, with the nitrogenous bases in the middle. Pauling's model could not exist in cells, because cells are a water matrix. The sugar-phosphate backbone would repel itself because of the oxygens located around it and the electrons of the atoms would be repelled. The bases would also not be able to stack properly and it would contribute to a lot of instability in the molecule that is meant to be the blueprint of life.