Lecture 2 - Protein Structure Flashcards
What is a protein?
A subunit called amino acids
How many essential amino acids are there?
20
What is the purpose of proteins?
Important for diverse functions in the body which include hormones, enzymes, structure and transport
How can a protein lose it’s function?
Denature which leads it’s shape to change
What are the three groups for Amino Acids?
Acid Group, Amino Group, R Group
What is condensation?
Removal of water which joins an Amino Acid together
What is hydrolysis
Addition of h2o which removes a dipeptide bond
What is the purpose of Primary Structure?
Linear order of amino acids
What is the purpose of Secondary Structure?
Localized folding into pleated sheets and helices
What is the purpose of Tertiary structure
The 3D shape of the entire protein in space
What is the function of Quaternary structure?
Combination of more than one polypeptide bond
What bonds are involved in the maintenance of tertiary and Quaternary structures
- Hydrogen bonds
- Hydrophobic interactions
- Polypeptide backbone
- Disulfide bridge
- Ionic Bond
What decides if an Amino Acid can fold?
The sequence and properties of amino acids
What is a protein structure?
Supports the position of the active site
What is the binding site?
Bind and orients substrate(s)
What is the Catalytic site?
Reduces chemical activation energy
How does extreme heat cause a loss of function?
Denatures the protein causes its to shape function.
What is a mutation?
A variant that causes disease
What is a Variant?
A change in sequence
What is polymorphism?
A variant that does not result in disease
How are proteins numbered
First amino acid usually an M from N terminal to the end of chain C- terminal
How does a mutation cause a disease?
Mutation in the genome can result in changes of the protein sequence and therefore alters the structure
What are the ways in which Mutations occur?
Wild Type Deletion Insertion Substitution Nonsense
How are protein substitution mutations written?
p.G89R p= designated protein sequence G= Original or wild amino acid R= Replacement amino acid 89= Position
How do we write deletion proteins
p.F508del p= designated protein sequence F= Original or wild amino acid 508= Position in Sequence Del= Deletion, no replacement amino acid
How are insertion mutations written?
p.K2_L3Q
P= Designates a protein sequence K= Original or wild amino acid _ = Position in sequence L= Replacement amino acid
How is Sickle cell aneamia caused?
Substitution mutation causes sickle cell aneamia
