Protein Structure Vocabulary

Flashcards covering fundamental vocabulary, chemical structures, and properties of proteins and amino acids.

Protein

A polymer built from amino acids that provides cells with their shape and structure and performs most of their activities.

Amino Acid

A small organic monomer containing both an amino group and a carboxyl group that serves as the building block of proteins.

Peptide Bond

A covalent chemical bond formed between the carbonyl group ($C=O$) of one amino acid and the amino group ($-NH-$) of a second amino acid.

Polypeptide Backbone

The repeating core structure of a polypeptide chain formed by all component atoms except the variable R-groups (side chains).

N-terminus

The amino terminus located on one end of a polypeptide chain where an unattached amino group ($-NH_3^+$) sticks out; amino acids in the chain are numbered starting from this end.

C-terminus

The carboxyl terminus located on one end of a polypeptide chain characterized by an unattached carboxyl group ($-COO^-$) sticking out.

Side Chain (R-Group)

The variable portion attached to the central carbon of an amino acid (with 20 standard options) that determines its specific chemical characteristics.

Central Carbon

The core carbon atom in an amino acid that forms four bonds: one to an amino group, one to a carboxyl group, one to a hydrogen atom, and one to an R-group.

Ribosome

A large protein complex that catalyzes peptide bond formation between amino acids.

Amino Acid Sequence

The specific ordered linear arrangement of amino acids within a polypeptide chain, numbered sequentially starting from the N-terminus.