Question

The base analog 5-bromouracil is capable of base pairing with which of the following bases? Select all that apply.

(A question about specific bases and pairing would need to be provided for options)
A) Adenine
B) Guanine
C) Cytosine
D) Thymine

Answer 1

The base analog 5-bromouracil is capable of base pairing with both adenine (A) and guanine (G), the latter due to its tautomeric forms leading to mutations by base pairing errors.

Step-by-step explanation:

The base analog 5-bromouracil can base pair with adenine (A) and guanine (G), acting as a mutagen that can lead to base pairing errors during DNA replication. Normally, uracil (or thymine in DNA) pairs with adenine, forming two hydrogen bonds. However, when 5-bromouracil substitutes for thymine, it can occasionally mispair with guanine, due to its ability to exist in two forms (keto and enol); it pairs with adenine in its common form and with guanine in its rare enol form. Consequently, 5-bromouracil is known to facilitate a change from an AT base pair to a GC base pair after several rounds of replication.