Classification of Amino Acids Flashcards
Structure of Amino Acids
![](https://s3.amazonaws.com/brainscape-prod/system/cm/308/789/688/a_image_thumb.png?1587058035)
Acidic AAs
- Aspartic Acid
- Glutamic Acid
Aspartic Acid
Asp, D
aspartate - the anionic/deprotonated form
(how this amino acid is observed at physiological pH)
![](https://s3.amazonaws.com/brainscape-prod/system/cm/308/786/432/a_image_thumb.png?1587055505)
Glutamic Acid
Glu, E
glutamate - the anionic/deprotonated form
(how this AA is observed at physiological pH)
![](https://s3.amazonaws.com/brainscape-prod/system/cm/308/786/649/a_image_thumb.png?1587055645)
Basic AAs
- Lysine
- Arginine
- Histidine
Lysine
Lys, K
pKa = 10
cationic/protonated at physiological pH
![](https://s3.amazonaws.com/brainscape-prod/system/cm/308/786/798/a_image_thumb.png?1587055789)
Arginine
Arg, R
pKa = 12 at physiological pH
cationic/protonated at physiological pH
![](https://s3.amazonaws.com/brainscape-prod/system/cm/308/786/872/a_image_thumb.png?1587055835)
Histidine
His, H
pKa = 6.5 at physiological pH
can either be protonated (acidic) or deprotonated (basic)
![](https://s3.amazonaws.com/brainscape-prod/system/cm/308/786/905/a_image_thumb.png?1587055944)
Hydrophobic (Nonpolar) AAs
- Glycine
- Alanine
- Valine
- Leucine
- Isoleucine
- Phenylalanine
- Tryptophan
Characteristics of Hydrophobic/Nonpolar AAs
- either have aliphatic or aromatic side chains
- hydrophobic residues tend to associate with each other rather than with water
- therefore are found on the interior of folded globular proteins, away from water
- the larger the hydrophobic group, the greater the hydrophobic force repelling it from water
Glycine
Gly, G
aliphatic side chain
![](https://s3.amazonaws.com/brainscape-prod/system/cm/308/787/831/a_image_thumb.png?1587056399)
Alanine
Ala, A
aliphatic side chain
![](https://s3.amazonaws.com/brainscape-prod/system/cm/308/787/963/a_image_thumb.png?1587056443)
Valine
Val, V
aliphatic side chain
![](https://s3.amazonaws.com/brainscape-prod/system/cm/308/788/010/a_image_thumb.png?1587056489)
Leucine
Leu, L
aliphatic side chain
![](https://s3.amazonaws.com/brainscape-prod/system/cm/308/788/078/a_image_thumb.png?1587056554)
Isoleucine
Ile, I
aliphatic side chain
![](https://s3.amazonaws.com/brainscape-prod/system/cm/308/788/161/a_image_thumb.png?1587056594)