Protein Structure And Function Flashcards
(26 cards)
How many different enzymes (approximately) does an e.coli cell contain?
2000
What type of protein is haemoglobin?
A transport protein. Haemoglobin transports oxygen around the body.
What two main things to transport proteins do?
Move molecules around the body and move molecules across membranes.
What are some examples of structural proteins?
Fibroid -> in silk
Collagen -> in connective tissue
Keratin -> In hair, skin, and feathers
What type of protein is a hormone?
Communication
What are some examples of movement proteins?
Actin and myosin
What type of proteins are antibodies?
Defence
What is the basic structure of a protein?
Carbon in the middle, amine group, carboxylate group, and the rest of the structure
Proteins are polymers of what?
Amino acids!
Proteins fold into 3D structures stabilised by non-covalent interactions. What are these interactions?
Hydrogen bonds
Ionic bonds
Hydrophobic bonds
What are hydrogen bonds?
Weak electrostatic bonds formed when a highly electronegative element (N, O, F, S) bond to a hydrogen. They are collectively strong.
What are ionic bonds?
Electrostatic interactions between +ve and -ve charges
What are hydrophobic interactions?
Non-polar sidechains cluster together excluding water and allowing H2O to form H bonds between themselves
What are Van der Waals?
Weak forces between adjacent neutral atoms
What is the primary structure of proteins ?
The amino acid sequence
What is the secondary structure of proteins?
An alpha helix or a beta sheet.
How is the secondary structure of proteins stabilised?
By hydrogen bonding
How is the tertiary structure of proteins stabilised?
Hydrogen bonding, ionic bonds, hydrophobic interactions and disulphide bonds
What is the quaternary structure of proteins?
The arrangement of subunits in proteins containing two or more polypeptide chains
Protein conformation is flexible. What does this mean?
Proteins are not rigid, their structure can change
What is the main way that protein conformation can be destroyed/denatured?
Heat!!!!
What are protein domains?
An Independently stable part of a polypeptide, usually with a specific function
How can evolution of new proteins occur (domains)?
Domain swopping
An antibody will recognise a small part of an antigen, what is this called?
The epitope
