1.2(c) Protein Structure, Ligand Binding and Conformational Change Flashcards
What do R groups give amino acids
Their unique chemical properties
What are the 4 types of amino acids
Acidic (negatively charged)
Basic (positively charged)
Polar
Hydrophobic
What are acidic aminos acids
Generally, have a -COOH on the R group and are negatively charged. They are strongly hydrophilic
What are basic amino acids
Have an NH3 or NH2 group and are positively charged. They are strongly hydrophilic
What is a polar amino acid
They all have a nitrogen, oxygen or sulphur (NOS). They are hydrophilic as they form weak hydrogen bonds with water molecules
What is a hydrophobic amino acid
The R group does not contain OH, COOH, NH2 or SH, they are carbon heavy. They are hydrophobic and non-polar and often have benzene rings
Name the 4 types of protein structure
Primary
Secondary
Tertiary
Quaternary
What is primary structure
Amino acid sequence that are synthesised into a polypeptide
What is secondary structure
Alpha-helix, beta pleated sheets and turns.
How are turns brought about
Changes in direction are caused by hydrogen bonding along the back bone
Beta pleated sheets can be…
Parallel of Anti-parallel
What is tertiary structure
Refers to the overall folding of the polypeptide and is stabilised by different interactions between R groups e.g., Hydrophobic interactions, ionic bonds and disulphide bridges
What is a prosthetic group
Non-protein parts that give proteins extra function e.g., haem in haemoglobin
What is quaternary structure
2 or more connected polypeptide subunits
What is a ligand
A substance that can bind to a protein
