Page 230 - The Manga Guide to Biochemistry
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Because of the existence of this hydroxyl group, RNA is known to undergo
autolysis (a self-inflicted decomposition) due to a phenomenon known as base
catalysis.
Autolysis!
If you think of the O and the H of a hydroxyl group as a couple, then H is the
“playboy” that can be tempted by bases that exist around the RNA.
It’s important to note that these aren’t the A, U, C, and G bases we’ve
been talking about so far. In this context, a base is a substance that can accept
a proton (H+), such as a hydroxide ion (OH-). Bases can be thought of as the
chemical opposite of acids, because they neutralize each other.
So the 2´-OH proton is extracted by a base?
That’s right. Then the lone oxygen goes looking for a new partner to bond with.
Actually, after the proton is extracted, the oxygen (O-), which carries a nega-
tive charge, will bond with the phosphate (P) in the phosphodiester bond
at the neighboring 3´ position (that is, the important bond connecting two
ribonucleotides).
216 Chapter 5
