Amino acids, Peptides, and Proteins Flashcards
1
Q
Amino acid general structure
A
- hydrogen
- central alpha carbon
- amino acid group (NH3+)
- carboxyl group (COO-)
2
Q
How do the 20 amino acids differentiate from each other?
A
- by their side chain (r) groups
3
Q
Stereoisomers
A
- L and D isomers (proteins are made almost exclusively from L
4
Q
Text groups of amino acids:
A
- non-polar
- aromatic
- polar, uncharged
- polar, positively charged
- polar, negatively charged
5
Q
The 20 amino acids include:
A
- Glycine
- Alanine
- Valine
- Leucine
- Isoleucine
- Proline
- Methionine
- Tyrosine
- Phenylalanine
- Tryptophan
- Cysteine
- Asparagine
- Glutamine
- Serine
- Threonine
- Lysine
- Arginine
- Histidine
- Aspartate
- Glutamate
6
Q
Glycine
A
- Gly
- G
- Only amino acid who doesn’t have a chiral center
- Non polar
7
Q
Alanine
A
- Ala
- A
- single hydrocarbon side chain
- Non polar
8
Q
Valine
A
- Val
- V
- 2 hydrocarbon side chains
- non polar
9
Q
Leucine
A
- Leu
- L
- 5 hydrocarbon side chains (one extended on the third carbon)
- non polar
10
Q
Isoleucine
A
- Ile
- I
- 5 hydrocarbon side chains
(one extended on the second carbon) - non polar
11
Q
Proline
A
- Pro
- P
- only molecule that has a ring directly off central carbon that is closed
- form tight turns
- non polar
12
Q
Methionine
A
- Met
- M
- Sulfur in the middle of side chain
- non polar
13
Q
Tyrosine
A
- Tyr
- Y
- Has ring off side chain with an OH group
- aromatic
14
Q
Phenylalanine
A
- Phe
- F
- ring off side chain
- aromatic
15
Q
Tryptophan
A
- Trp
- W
- two rings off side chain
- aromatic
16
Q
Cysteine
A
- Cys
- C
- Only other amino that has sulfur
- polar uncharged
17
Q
Asparagine
A
- Asn
- N
- double bonded O off side chain
- polar uncharged
18
Q
Glutamine
A
- Gln
- Q
- double bonded O off side chain of two carbons
- polar uncharged
19
Q
Serine
A
- Ser
- S
- OH bonded off side chain
- polar uncharged
20
Q
Threonine
A
- Thr
- T
- OH bonded off side chain with extra carbon
- polar uncharged
21
Q
Lysine
A
- Lys
- K
- Ends in positive charge NH3+
- polar, positive
22
Q
Arginine
A
- Arg
- R
- Ends in positive charge, splits like a Y
- polar positive
23
Q
Histidine
A
- His
- H
- unique side chain of 5
- polar positive
24
Q
Aspartate
A
- Asp
- D
- negatively charged, ends in two O’s branched
- polar negative
25
Q
Glutamate
A
- Glu
- E
- negatively charged, ends in two O’s with 2 carbon chain
- polar negative
26
Q
Non-polar group
A
- mainly hydrocarbon side chains
- often the molecules that are buried in the center of a protein (don’t want to be exposed to water)
- no charge residues
- absence of hydrogen bonding capabilities
27
Q
Aromatic
A
28
Q
Phosphorylation
A
mechanism to regulate protein function
