Drug receptor interactions, Protein and Nucleic acids Flashcards
what is this
agonist
have affinity and stimulate response
what is this
antagonist
have affinity but no response
this is an ion gated channel
how does ion gated channels work
ionic interaction between CO2 of the receptor and an inducer with NH2Me
How do g-protein coupled receptors work?
External messenger that binds to receptor which causes conformational change intracellularly
This change allows binding of a secondary messenger which is cleaved
A part of this molecule will bind to an ezyme to trigger effect
What are the types of agonists
full agonist - exert full effects
partial agonist - lesser extent of binding and gives some effect
inverse agonist - exert full reverse effect
What are the different types of antagonist
competitive inhibition - bind to active site as per agonist but doesnt cause conformational change
non-competitive inhibition - bind to allosteric binding which causes a conformational change to the active site to prevent agonist binding
umbrella effect - shields binding sites
What are the forces that allow receptor bonding
van der waals forces
covalent
ionic
charge transfer bonding - between electron rich and electron dificient
hydrogen bonding
hydrophobic bonding
Describe the structure of a protein
consists of amino acids linked by peptide bonds
Usually between COOH and NH2
Are chiral
Can form zwitter ions
What is the primary structure of a protein
A sequence of amino acids
What is the secondary structure of a protein
Alpha helix
Hydrogen bond every 4th amino acid
rod-like struture
can become superhelix
Beta pleated sheet
H bonding between different primary structures
Beta turn
H bonding between 1st and 3rd amino acid
What is the tertiary structure of a protein
Overall 3D structure of polypeptide
contains several bonds between amino acids
hydrophobic
disulfide bridge
ion-dipole
salt bridge
van der waals
What is the quaternary structure of a protein
spatial arrangement of protein sub unit
What are some post-translational modifications for proteins
N-terminal acetylation
hydroxylation of proline residues
carboxylation of glutamate
phosphorylation og OH
linkage of carbohydrates
cleavage into smaller peptides
What are enzymes
they increase rate of reversible bioreactions by lowering activation energy
no influence on reactant concentrations
provides favourable environment - orientates correctly, weaken bonds
What sort of bonding do enzymes undertake
ionic bonding
hydrogen bonding
dipole-dipole interactions
Koshlands theory of induced fit - substrate induces active site conformational change
What are cofactors
Non-protein required to allow for enzyme activity
metal ions or small organic molecules
What are the types of enzyme inhibitors
competitive, reversible
-bind more strongly than substrate
non competitive, reversible
-allosteric inhibition
non competitive, irreversible
-covalent bonding
What is a primary structure of a DNA
sequence of RNA chain
What is the secondary structure of DNA
double helix
antiparallel
stabilised by hydrogen bonding
phosphate outside
What do tertiary structure of DNA look like
supercoiled helix
by topoisomerase
Secondary RNA structure
no double helix
some H bonding between nucleobase within one strand
