Keratin is a protein composed of 18 amino acids, with cysteine, cystine, serine, glutamic acid, glycine, threonine, arginine, valine, leucine, and isoleucine being the most abundant. Keratin is found in various parts of the body, including hair, nails, and skin.
Keratin Composition:
- Amino Acids: The primary building blocks of keratin are amino acids, specifically 18 different types.
- Sulfur Content: Keratin's structure is influenced by the presence of sulfur-containing amino acids, particularly cysteine and cystine. These amino acids contribute to the formation of disulfide bonds, which are crucial for keratin's strength and stability.
- Other Elements: In addition to amino acids, keratin also contains other elements, such as carbon, oxygen, nitrogen, and hydrogen.
Types of Keratin:
- Alpha Keratin (α-keratin): Found in mammals and is known for its fibrous nature and low sulfur content. It is the primary protein found in hair.
- Beta Keratin (β-keratin): Found in reptiles, birds, and amphibians. This type of keratin has a higher sulfur content and forms a tougher, more rigid structure, as seen in scales, claws, and feathers.
Keratin's Role:
Keratin's unique chemical composition gives it properties that make it ideal for its structural functions:
- Protection: Keratin provides a barrier against environmental damage, such as abrasion and UV radiation.
- Support: Keratin helps maintain the shape and integrity of tissues like skin, hair, and nails.
- Strength: Keratin's structure gives it strength and resilience, which is vital for the function of hair, nails, and skin.
