DNA has revolutionized the biological science and its structure since last century and many elements are continuously added to the DNA facts. We will try to enlighten ourselves with the bonding of the DNA, possible conformations and DNA solutions. It was first thought that B-form DNA symbolizes the conformation of most of the DNA present in living cell and this analysis was extracted through a chemical technique known as X-ray diffraction.
This model or technique was utilized in the first part of DNA revelations and it explained the basic structure of DNA and signified the elements which contribute to the beautiful architecture of DNA. But with the help of other techniques it was revealed that the other form or conformations of DNA existed. Now the other forms are differentiated from the B-form by the variation in the structure i.e. distinct minor and major grooves and the location of pairs of the bases as they have the perpendicular orientation with the axis of helix
Then there were many experimental methods which were found to be utilized in order to find the other parameters of the B form DNA like the base pairs were repeated in helical by per turn in the mixed sequence of DNA B-form, which is found to be approximately 10.5/turn. Now as discussed earlier that conditions of solution is again important in this regard but its just and average that is taken and other factors also have impacts in the conformation of DNA model as double helix structure. The X ray diffraction method utilized for analyzing the B-form DNA through single crystals and the molecule which was utilized was dodecamer in which the hydrogen bonding is in motion for base pairing of the molecules.
This dodecamer structure was very much similar to B form DNA but showed some variations in local sequence. Now coming to explore some more DNA facts, it is now established that not all the pairs of DNA base are perpendicular and in their structure view they represents a propeller-twist. The bases like purine and pyrimidine are twisted in a way that they make a vision of propeller blades. Moreover the axis of helix is also curved but not straight and represents a variation in sequence of conformation. Interestingly this curvature of DNA structure due to the biological functions it performs stands out to be an important feature in DNA structure. These variations as explored during earlier experimentation of DNA, revealed the fact that other forms of DNA existed and then thereafter analyzing, termed as C and D forms of DNA.
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