Proteins and Amino Acids

2017-10-02


What kinds of materials go into building a factory?


wikipedia
Shi et al. (2009) JCS, Song et al. (2009)
See International

How does one chemical (protein) achieve such a vast array of functions?

Conceptual goals

  • The sequence of a protein determines is structure, which determines its function
  • Understand how concatenating relatively few amino acids can lead to a huge diversity of possible functional proteins.

Skill goals

  • Identify the amino acids based on their chemical structure.
  • Reason about how their individual chemistry leads to distinct biological roles.

The power of combinatorics!

  • Directional (has front and back)
  • You can make it as long as you want
  • You can swap in any car at any point in the train
Planet Diecast

On your handout, circle amino acids whose sidechain participates in:

  • hydrophobic effect
  • Van der Waal's
  • hydrogen bonds
  • ionic interactions
  • covalent bonds (without enzymatic help)

Amino acids fill a large volume of "property space"

Key points:

  • Proteins are formed from amino acids, arranged into a chain
  • Chain is formed by a series of peptide bonds
  • Because there are 20 naturally-occuring amino acids, a vast number of sequences are possible
  • These 20 amino acids cover a wide range of chemical properties

Big ideas

Amphipathic molecules lead to large-scale structure

Combinatorial polymers allow creation of a vast number of molecules