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Cordycepin, or 3-deoxyadenosine, is a derivative of the nucleoside adenosine, di

ID: 68489 • Letter: C

Question

Cordycepin, or 3-deoxyadenosine, is a derivative of the nucleoside adenosine, differing from the latter by the absence of oxygen in the 3' position of its ribose part. It was initially extracted from fungi of genus Cordyceps. Cordycepin inhibits poly(A) synthesis at low concentrations and RNA synthesis at higher concentrations. a. Please draw the structure of cordycepin. b. What is the basis of inhibition by cordycepin? c. Why poly(A) synthesis is more sensitive to cordycepin? d. Does codycepin need to be modified to exert its effect? Explain

Explanation / Answer

a. Structure of cordycepin

Cordycepin, or 3'-deoxyadenosine, is a derivative of the nucleoside adenosine, differing from the latter by the absence of thehydroxy group in the 3' position of its ribose part. It was initially extracted from fungi of genus Cordyceps, but is now produced synthetically.

Because cordycepin is similar to adenosine, some enzymes cannot discriminate between the two. Therefore, it can participate in certain biochemical reactions

Molecular formula

C10H13N5O3

b. Because cordycepin lacks a 3-OH group, it cannot participate in 3 5 bond formation.

c. Because the poly(A) tail is a long stretch of adenosine nucleotides, the likelihood that a molecule of cordycepin would become incorporated is higher than with most RNA.

d.Yes cordycepin need to be modified to exert its effect, by converting into cordycepin 5-triphosphate.