Chapter 2: 2.1 Amino acids Flashcards
- How many amino acids are there?
- What is the basic structure of an amino acid?
- 20 amino acids
- Hydrogen, Carboxylic Acid Group, Amino Group, Side Chain (R group)
What are the ways that each amino acid can be named?
- The full name
- A three letter identifier
- A single letter identifier
– amino acids can be acquired through diet
10
List:
The 10 amino acids can be acquired through diet
- Phenylalanine (F)
- Histidine (H)
- Isoleucine (I)
- Lysine (K)
- Leucine (L)
- Methionine (M)
- Arginine (R)
- Threonine (T)
- Valine (V)
- Tryptophan (W)
Amino acid composition drastically impacts…
- Protein function
- Protein characteristics
Define:
Site directed mutagenesis
Key amino acids are replaced with other amino acids
What can site directed mutagenesis lead to?
- Eliminate protein function
- Alter structure
- Protein unfolding
What 3 key amino acids? Describe their side chain structure
- Alanine: Single methyl group side chain
- Proline: Side chain forms a ring connected to teh amino group of the backbone
- Tryptophan: Aromatic side chain
Describe:
The behaviour/function of Alanine
Used to virtually delete amino acids during site directed mutagenesis
Describe:
The behaviour/function of Proline
Much more rigid than other amion acids
* Often found in turns and the beginning of alpha helices in proteins
Describe:
The behaviour/function of Tryptophan
Is fluorescent and absorbs UV light (280 nm), allowing proteins to be monitored
Amino acids are Zwitterions.
Define Zwitterions
Molecules with functional groups containing both a positive and a negative charge, resulting in a net neutral charge
Define:
pKa
The pH value at which a charged functional group is half protonated and half unprotonated
State:
The pKa value of:
1. Carboxylic acid group
2. Amino group
- ~2
- ~10
If pH < pKa…
Protonated form is predominant
