Chapter 5 - Primary Structure of Proteins

Test #3 for Biochemistry

What are enantiomers?

Molecules with at least one chiral carbon.

What are chiral carbons?

A carbon atom that is bonded to four different atoms or groups.

What do the vertical lines in a Fischer projection? The horizontal lines?

The vertical bonds represent the bonds going into the page (away from the viewer), and the horizontal bonds represent them coming out of the page towards the viewer. 

What is the method used to determine an L-amino acid?

CORN - COO-, R, N, in a clockwise fashion. 

For amino acids with multiple chiral carbons, how would it be drawn?

Use a combination of the Fischer projection and the Cahn-Ingold-Prelog system.

What are the other two ways to draw enationmers?

Wedge-and-dash, and Newman projections

What is a racemic mixture?

A 50/50 blend of two enantiomers, which are mirror-image molecules. 

Why are most amino acids in L form?

The chiral center of amino acids was resolved, and only L-amino acids were incorporated into proteins.

Amino acids can be classified as an ampholyte. What does this mean?

This means they can act as either an acid or base.