Proteins Flashcards
What is a glycoprotein?
A compound composed of protein and carbohydrate
What is the name if the post translational modification where a sugar molecule binds to an amino acid on a protein?
Glycosylation
Where does glycosylation occur?
In the ER and golgi apparatus
What is the glycated form of haemoglobin a marker for?
Diabetes
How is glycated haemoglobin a marker for diabetes?
Because if the insulin is not working the glucose remains attached to the haemoglobin
What is a lipoprotein?
Protein and lipids that are either covalently of non-covalently bonded together
What is the function of a lipoprotein?
To transport insoluble fats and cholesterol in the blood
Give 2 examples of lipoproteins
HDL LDL
What is a metalloprotein?
A protein molecule with a bound metal ion
What fraction of proteins require a metal ion to carry out their specific role?
1/3
Give and example of a metalloprotein?
Haemoglobin requires Fe
How many subunits does haemoglobin compose of?
4
What kind of mutation is sickle cell anaemia?
Substitution
What affects the sickle cell being able to transport oxygen?
Its shape
Do sickle cells give up O2 easily?
Yes - give it up to the tissues more readily
What shape do sickle cells have?
Moon crest cell
What kind of protein is collagen?
Fibrous protein
How many polypeptides are coiled around each other to form collagen?
3
What does the lack of Vitamin C cause?
Scurvy
What are LDL receptors composed of?
Glycoproteins
What do LDL receptors do to LDL?
Internalise it
How do LDL receptors internalise LDL?
Engulf the receptor and LDL
Once the LDL had been engulfed what happens to it?
It is broken down in lysosomes
What can go wrong with LDL receptors?
No receptors Receptors never make it to cell surface Receptors can't bind LDL Receptors can't internalise on binding of LDL Receptors don't release the LDL
What is FH caused by?
Mutation in LDL receptor
Meaning there are elevated LDL levels
What do FH cause?
Cholesterol to be deposited in the skin, tendon, arteries
Early cardiovascular disease
What can be used to separate out proteins?
Electrophoresis
