Which functional group in cysteine residues can form bridges that help stabilize a protein's tertiary structure?

A) amino
B) carbonyl
C) hydroxyl
D) phosphate
E) sulfhydryl

Cysteine Residues

The amino acid units in proteins that contain a thiol group, often involved in the formation of disulfide bonds that stabilize protein structure.

Tertiary Structure

The three-dimensional shape of a protein molecule formed by bends and folds of its polypeptide chain.

Sulfhydryl

A functional group with the structure R-SH, where R is an organic alkyl or aryl group and SH denotes a sulfur atom bonded to a hydrogen atom, important in protein structure.