Protein Structure

This post will be mainly going over stuff that I've talked about before, but I'm including it for completeness and because I love HDs more than is really healthy. Anyhow...

Know the general formula of an amino acid.

An amino acid has an alpha-carbon joined to four different groups: a carboxyl group, an amino group, a hydrogen atom and a side chain, often referred to as R.

Be able to list the major groups of amino acids based on their side chains (e.g. basic, acidic, uncharged polar, nonpolar).

See my first post on amino acids.

Be able to describe the formation of a peptide bond.

See my earlier post on peptide bonds.

Understand that evolutionarily conserved proteins typically show amino acid sequence homology.

This dot point kind of speaks for itself. Proteins that have more or less retained their function over time and between related species tend to have similar or identical sequences.

Know the types of noncovalent and covalent interactions that may play a role in determining the conformation of a polypeptide.

See my earlier post on protein folding.

Be able to describe an α-helix and a β-sheet.
Be able to define the 1° (primary), 2° (secondary), 3° (tertiary) and 4° (quaternary) structure of a protein.

See my post on the levels of structure of a protein.

Be able to define a polypeptide domain.

A polypeptide domain is a region of a polypeptide that can fold independently into a stable structure. I *think* these domains might all have specific functions as well- for example, SH2 domains tend to bind to proteins that have phosphorylated tyrosine residues.