Lecture 3 - Introduction to Proteins Flashcards
What are proteins described as?
The workhorses of the cell
What are proteins and what do they form
Non-branching polymers that form macromolecules (50 - 100A in size)
What is 1A
10^-10 m
What is each protein composed of?
A specific sequence of amino acids joined together by chemical bonds called peptide bonds
What is unique to each protein?
The sequence of amino acids and the length of the sequence
How many different amino acids make proteins?
20
How is protein structure determined?
By protein crystallography, cryo-electron microscopy and NMR spectroscopy
What are the ways of depicting chemical structure?
Skeletal, Ball and Stick, Space-filling
What are considered enzymes?
Proteins with the -ase suffix
What is insulin?
A cell signalling hormone
What is the function of insulin?
After a meal, insulin is generated and binds to the insulin receptor to signal cells to take up glucose
What is Trypsin involved in
Digestion
How does Trypsin work
Breaks down proteins during digestion.
What are enzymes that break down proteins called
Proteases.
What do viruses and bacteria do
Make proteins, like proteases too.
What does HIV do?
Makes a protease (HIV Protease) which is essential for its replication. Treatment can inhibit it
What is amylase involved in?
Digestion
What is the function of amylase?
To break down starch into sugars
Where is amylase found?
In the saliva as well as pancreatic juices
What is alcohol dehydrogenase involved in?
Metabolism
What is the function of alcohol dehydrogenase?
Helps metabolise ethanol
What is hexokinase involved in?
metabolism
What is the function of hexokinase?
Adding a phosphate to glucose, after glucose has been taken up by the cell
What are kinases?
Enzymes that usually add phosphate groups to molecules
