Proteins Flashcards
What are proteins formed from?
Amino acids.
How many bases code for one amino acid?
Three.
What is the bond formed between amino acids in a condensation reaction?
A peptide bond.
What is the primary structure of a protein?
The sequence and number of amino acids in a polypeptide chain.
What is the secondary structure of a protein?
The way the polypeptide chain twists into 3d shapes like alpha helices and beta pleated sheets due to weak hydrogen bonds forming between the N-H and C=O on amino acids.
What is the tertiary structure of a protein?
The way the protein folds into its complex, unique, 3D structure due to hydrogen bonds, ionic bonds, disulphide bridges and hydrophobic interactions of the R group of the amino acids.
What is the quaternary structure of a protein?
When a protein is made of 2 more polypeptide chains joined together. This sometimes involves a prosthetic group.
What is an example of a quaternary structure?
Haemoglobin, which has 4 tertiary structures bonded together with a prosthetic group of iron in the middle.
Which protein structure is only had by some proteins?
Quaternary structure.
How do you test for protein and what is the positive result?
Add biuret, will turn purple if positive.
What is activation energy?
The minimum amount of energy required for a chemical reaction to occur / the particles to collide.
What is a substrate?
The molecule which is complementary to the enzyme’s active site.
What is an active site?
Where the substrate binds to the enzyme.
As a substrate approaches its complementary enzyme - what happens?
The proximity of the substrate causes a conformational change to the active site and tertiary structure of the entire enzyme (change of shape) which allows the active site to become functional and an enzyme-substrate complex to form.
What factors affect rate of reaction?
- Temperature
- Concentration
- Non-competitive inhibition
- Competitive inhibition