Week 4: PROTEIN DESIGN PART I

Part A- Conceptual Questions

How many molecules of amino acids do you take with a piece of 500 grams of meat? (on average an amino acid is ~100 Daltons)
Beef contains approximately 22g of protein per 100g 22 grams x 5= 110gram of protein in 500g of beef 1 Dalton ≈ 1g/mol 110g of protein / 100g/mol= 1.1mol 1.1x6.02×10²³= 6.6x10²³

Why do humans eat beef but do not become a cow, eat fish but do not become fish?

Why are there only 20 natural amino acids?

20 seems to be is the most optimum, photochemically. It is stable enough to build functioning proteins. There are 64 possible condons that need to work with 20 amino acids making it robost to minimise mutations. Having more would make it difficult to create suitable tRNA.

Can you make other non-natural amino acids? Design some new amino acids.

Where did amino acids come from before enzymes that make them, and before life started?

If you make an α-helix using D-amino acids, what handedness (right or left) would you expect?

Can you discover additional helices in proteins?

Why are most molecular helices right-handed?

*Why do β-sheets tend to aggregate?

What is the driving force for β-sheet aggregation?