Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
19 Cards in this Set
- Front
- Back
|
What are the four levels of protein structure?
|
1. The primary structure which an be alpha pleated sheet or beta helix.
2. Secondary structure which is bonds between the parallel sheets or the helix. 3. Tertiary structure which is how the helixes and sheets join together. 4. And quaternary structure where the different combinations effect each other. |
|
|
The primary structure is also known as the?
|
Amino acid sequence.
|
|
|
What causes the secondary structure?
|
Hydrogen bonds between the amide groups of the polypeptide chain.
C=O-------H-N |
|
|
Hydrogen bonds occur between?
|
A positive H and a negative O or a N lone pair.
|
|
|
List three non covalent side chain interactions which dictate tertiary structure.
|
1. Hydrogen bonding between side chains.
2. Hydrophobic interactions/ london forces. 3. Ionic interactions between side chains / salt bridges. |
|
|
Name a covalent side chain interaction that affects the tertiary structure.
|
Disulfide bonds.
|
|
|
What is quaternary structure influenced by?
|
Side chain interactions between multiple polypeptides.
|
|
|
List four ways that proteins can be denatured.
|
H-bonding substances disrupt hydrogen bonding between chains.
Detergents disrupt hydrophobic interactions / london forces. Changes in pH disrupt ionic interactions between side chains. |
|
|
How do phenols and alcohols act as antiseptics?
|
They can dissolve in and pass through bacterial cell membranes, then denature proteins inside the cells.
|
|
|
How do heavy metals denature proteins?
|
They bind strongly to the cysteine residues.
|
|
|
In regards to the isoelectric point what does it equal?
|
pI = 1/2 ( pKa 1 + pKa 2)
|
|
|
Which pH are amino acids ionic at?
|
Any.
|
|
|
With zwitterions the charge for the acid is always?
|
Positive.
|
|
|
To discover which species is dominant at the isoelectric point you?
|
It is the substance whose pKa os closest to the isoelectric point value.
|
|
|
The charge of an amino acid depends on the.... Of the solution?
|
pH
|
|
|
If pH is..... Than the pI charge is positive.
|
Lower.
|
|
|
Hydrogen side chain is called?
|
Glycine (GLY)
|
|
|
A methyl side chain is called?
|
Alanine (ALA)
|
|
|
Dimethyl side chain is called?
|
Valine (VAL)
|
