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812 Chapter 26
Copyright © 2017 Pearson Education, Inc.
c.
O
N
HN
O
O
HO
dUMP
−
O
−
O O
P
O
e.
O
HO
guanosine 5 -triphosphate
GTP
OH
HN
N N
N
O
H
2
N
−
O
−
O O
P
O
−
O
P
O
O
−
O O
P
O
d.
O
N
HN
O
O
HO
UDP
OH
−
O
−
O O
P
O
−
O
P
O
O
f.
O
O
HO
OH
N
N N
N
NH
2
O
adenosine 3
9
-monophosphate
−
−
O O
P
AMP
3.
A hydrogen bond acceptor is indicated by
A
(it is an atom with a lone pair); a hydrogen bond donor is
indicated by
D
(it is an atom with a hydrogen attached to a nitrogen).
The
A
and
D
designations show that the maximum number of hydrogen bonds that can form are two
between thymine and adenine and three between cytosine and guanine. Notice that uracil and thymine have
the same
A
and
D
designations.
N
O
sugar
O
H
uracil
A
O
A
D
A
N
N
O
sugar
H
thymine
D
A
H
3
C
N
N
adenine
N
N
N
H
H
sugar
A
D
N
sugar
O
cytosine
A
A
D
N
H
H
N
N
guanine
O N
sugar
D
H
A
NH
H
D
N
N
N