L2- Protein summary Flashcards
how many different levels of protien strucutre
4 primary secondary tertiary quarternary
Primary
Structure and function
- peptide bonds
Secondary
Localised folding
- hydrogen bonds
Tertiary
ultimate folding of the protein
- disulphide, ionic, H bonds, Van Der Waals, hydrophobic
quartenrayr
multiple subunit
-disulphide, ionic, H bonds, Van Der Waals, hydrophobic
protein dentauration
losing confirmation of native state caused by breaking forces holding proteins together
what can denature proteins
- heat (vibration)
- pH (alters ionisation state of amino acids)
- detergents/organic solvents (disrupts hydrophobic interaction
example of protein misfolding which ca. cause disease
Transmissible spongiform encephalopathy e.g. BSE, Kuru, CJD
protein folding is not
random- driven by the need to find the most stable conformation
forces involved in maintaining proteins structure
- covalent
- electrostatic
- hydrogen
- hydrophobic
- van der waals
covalent bond e.g. peptide bond
covalent bonds are strong
- broken by a reducing agent
example of a covalent bond
disulphide bond between two cysteine
most proteins with disulphide bonds re
secreted e.g. ribonuclease
electrostatic interactsions
formed between electronegative atoms and a hydrogen bound to another electronegative atom
- salt bridges
- relatively strong
hydrogen bonds
electrostatic interactions between water and nitrogen, oxygen or fluorine
