Protein Structure and Classification

Introduction

• Discussion on amino acids transitioning into proteins.
• Focus on three-dimensional structure of proteins.
• Overview of classifying proteins and forming secondary structures.

Classification of Proteins

Simple Proteins

• Composed entirely of amino acids.

Conjugated Proteins

• Contain additional groups like metal ions, co-factors (vitamins), lipids, or carbohydrates.
• Example: Hemoglobin with heme prosthetic groups.

Fibrous Proteins

• Long strands or sheets of polypeptides.
• Hydrophobic and water-insoluble.
• Strong and flexible.
• Examples: Keratin (in fingernails), Collagen (in nose and ears).

Globular Proteins

• Spherical or globular in shape.
• Generally water-soluble; found in cytosol or outside cells.
• Contain several secondary structure elements.
• Functional variety: enzymes, regulatory proteins, etc.
• Example: Catalase (enzyme), Hemoglobin.

Functions of Proteins

• Enzymes: Catalyze reactions; names end in