Transcript Slide 1

The general molecular formula of an amino acid is RCH(NH2)COOH
However, it’s easier to ‘see’ the bonds that are present
by writing its structural formula:
H
O
O
C
R
C
H
N
H
carboxylic acid
group
H
amine group
Click to see what happens when these molecules are dissolved in water
A zwitterion is formed when a proton (a hydrogen nucleus) moves
from the carboxylic acid group to the amine group
H
O
O
-O
C
C
proton,
H+,
transfers
to the
amine
group
R
C
H
R
H
N
H
O
C
N+
H
H
H
H
The zwitterion ion forms when an amino acid is dissolved in water – and
this is how they are usually found in nature
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