DNA - are hydrogen or ester bonds involved between the nucleotides? What is the difference?

In the middle of the backbone of DNA are the nucleotides joined via hydrogen or ester bonds? What is the difference between the two? The literature seems to use both interchangeably with DNA.DNA - are hydrogen or ester bonds involved between the nucleotides? What is the difference?
The ester bond is a bond found specifically within the DNA chain it is linking the nucleotides together. The H+ bonds, are the weakened bonds between the DNA strands between the amino acids A,T,G,C.



(ester bonds) %26lt; l A -(H+ bonds)- T

%26lt; l T------H+--------- A

l C--------H+-------G

l G--------H+--------C



crappy diagram, but I hope it makes sense~DNA - are hydrogen or ester bonds involved between the nucleotides? What is the difference?
The question I was asked was, "What chemical bond joins nucleotides in the backbone?" Are they talking about the hydrogen bond between AT and CG, or the bond between the phosphate and pentose sugar (a peptide or ester bond?) or the bond between the AT/CG and the sugar (which is?)?

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DNA - are hydrogen or ester bonds involved between the nucleotides? What is the difference?
Hydrogen bonds are not covalent. They exist as intermolecule bonds between the two paired DNA strands. Adenine binds Thymine while Guanine binds Cytosine. The hydrogen bonds form the 'rungs' between the two DNA strands making them into the ladder structure. This allows correct alignment of the base pairs between the strands. DNA strands can be separated with heat then find their partner as they cool. See how to do a PCR reaction.

http://en.wikipedia.org/wiki/Base_pair

Hydrogen bonds form between a polar molecule with a hydrogen and another polar molecule that has a negative region. [The negative regions are most often OH (hydroxyl group) or NH (amine group).] The positive has to sit next to the negative region to fit the charges. Nucleotides are polar. This molecule can then make a hydrogen bond when it sits with opposing charges facing another polar nucleotide. Because these often involve very large molecules the many little pulls holding the two together become very powerful.

http://en.wikipedia.org/wiki/Hydrogen_bo鈥?/a>



A phosphate ester bond is covalent. This bond will not come apart when the strands are heated. The nucleoside combines with phosphate to form a nucleotide. Then phosphodiester bonds are formed between nucleotides to create the polymer DNA.



Covalent bonds are very powerful. They go to the heart of a molecule attracting the member atoms areas of full charge. Covalent bonding entails sharing of electrons, the entire negative electron cloud surrounds the deeply embedded, positive nuclei of the molecule. Covalent bonds balance the charges, 1 positive to 1 negative but sometimes the cloud hangs asymmetrically or is uneven so the charge is unevenly distributed over the molecule making it polar but still neutral.

http://en.wikipedia.org/wiki/Covalent_bo鈥?/a>
hydrogen bonds.



The difference is that hydrogen bonds are based on electrostatic forces and ester bonds are covalent bonds.



Note that the nucleotides that form a single strand are connected by ester bonds.