Page 117 - General Biochemistry

• Insulin is the smallest protein, with 51 amino acids in two chains linked by
cystine (disulfide) cross links:

Figure 28 insulin

Proteins

Protein Structure
• Primary (1°) Protein Structure
• Secondary (2°) Protein Structure
• Tertiary (3°) Protein Structure
• Quaternary (4°) Protein Structure
Twisting around various bonds in the polypeptide backbone gives proteins a
variety of shapes. Bond angles give rise to secondary structures. Then, the
secondary structures help drive the peptide folding that gives rise to tertiary
structure.
1) The primary structure: it is the linear sequence of amino acids.

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