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Ken Paul

What is the pH of guanine?

Damian Bennett  Follow

Pure guanine is a white, amorphous solid. As a solid, it doesn't has any pH.

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Ahmad Zahir  Follow

In Nanotechnology currently important area of research is self-assembly of nanoparticles.

DNA is consists of 4 bases A, T, G and C. Here we’re talking about Guanine. Now when we look for Guanine monomers, they can make G-quartet structures; G rich sequences contain guanine tetrads that can form from one, two, or four strands subsequently developing G-DNA superstructures. These properties can help in developing nanowires as these monomers self-assemble and help in getting the job done faster without use of additional forces.

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Aldino Piva  Follow

What is the pH of guanine?

As Jakob Krämer said, pH is not defined for a pure solid. It would have to be in aqueous solution to have any real meaning. And as the purine (not a nucleoside or nucleotide), it is quite insoluble in water. So the question “What is the pH of an aqueous solution of guanine?” can’t be answered because an aqueous solution of guanine doesn’t exist.

But even if we had the information that it was in aqueous solution, you would have to specify the concentration and we would have to know the first pKa in order to calculate a pH. And being insoluble doesn’t help to find that pKa experimentally.

It wouldn’t be too much of a leap, though, to suggest that the pKa of guanine might be quite similar to guanosine (the nucleoside, which is water-soluble), and that value is 10.6, so only about a factor of 10 weaker acid than [math]NH_4^+[/math].

I suspect the most acidic position is N[math]^1[/math] (in the purine numbering system) because loss of a proton at that position allows the six-membered ring to be fully aromatized, which confers an extra helping of stability on that particular anion.

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David York  Follow

Same as always in chemistry: the are proton (H+) acceptors, on the unshared pairs on the N atoms. So, nitrogenous bases.

In protein synthesis on the ribosome, peptide bond formation is catalyzed by a N atom of an A of the 23s rRNA. a classical acid catalyzed, base catalyzed process. The N first accepts an H+ from the amino N that will be in the peptide bond, enhancing the attack of that N on the C that will be in the bond. That is base catalysis by that adenine. It then donates the H+ to the 3′ O of the tRNA, breaking the bond to the C and leaving free 3′OH.

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David O'Malley  Follow
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Charles McDevitt  Follow

Guanine- C5H5N5O

I googled it. It is one of the four nucleobases found in nucleic acids DNA AND RNA.

Rest are - adenine, cytosine, thymine.

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Charles Martinez  Follow

First remember that within DNA, Adenine is always paired with Thymine, and Guanine is always paired with Cytosine.

So if Adenine is 15%, so also is Thymine 15%.

That leaves 70% which must be split equally between Cytosine and Guanine, so Guanine is 35%.

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Blaine Childress  Follow

What base does guanine pair with?

Cytosine

In DNA:
Guanine and cytosine form 3 hydrogen bonds between them.
Adenine and
thymine form 2 hydrogen bonds between them.

In RNA:
Guanine and cytosine form 3 hydrogen bonds between them.
Adenine and
uracil form 2 hydrogen bonds between them.

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