Proteins Flashcards
Where do Hydrogen binds occur in proteins?
Occur between the N-H group of one protein and the C=O of another group at a different section of the chain which causes folding
What is electrostatic attraction?
- The attraction between positively and negatively charged side chains
What are van der waals attractions
- weak, short range electrostatic attractions between uncharged molecules
What is disulphide bonding?
- formed between any 2 sulphides in an oxidation reaction
Where do peptide bonds occur?
Between N-H to C=O between each amino acid
- these are really rigid
What are the functions of Proteins?
- Act as a catalyst
- Transmit nerve impulses
- development
- movement
- growth
- immune protection
- mechanical support
- transport
What are the different ways in which an amino acid chain can fold?
- Linear
- Secondary
- Tertiary
- Quaternary
Explain linear folding
- This is a polypeptide chain that is bonded through peptide bonds
Explain Secondary folding
Secondary folding can occur as either Alpha helices or Beta sheets
What are Alpha Helices?
- secondary folding caused by hydrogen bonds between different sections of the polypeptide chain
After how many amino acids will there be a turn if it is bonded through hydrogen bonds?
- every 3-6 amino acids
why might an alpha helix structure become coiled around itself?
- to allow the hydrophobic sections of the polypeptide chain to be on the inside
What are beta sheets?
- Beta sheets are secondary folding that occurs due to hydrogen bonding forming sheets from a single polypeptide chain
- these can either be parallel or anti-parallel
Describe Tertiary folding
- A combination of the secondary folding
- This is devoid of symmetry
Describe quaternary folding
- this folding must contain more than 1 side chain which are attached through electrostatic attraction
