Amino acids are fundamental building blocks of proteins and have a very specific structure. Here's a breakdown:
Core Components of an Amino Acid
Each amino acid is built upon a central carbon atom. This carbon is bonded to four different groups:
- An Amino Group (-NH2): This group consists of a nitrogen atom bonded to two hydrogen atoms.
- A Carboxyl Group (-COOH): This group comprises a carbon atom double-bonded to an oxygen atom and single-bonded to a hydroxyl (-OH) group.
- A Hydrogen Atom (-H): One hydrogen atom directly attached to the central carbon atom.
- A Side Chain or R-Group: This is a unique chemical group that varies from one amino acid to another. It determines the specific properties of each amino acid.
Linking Amino Acids Together
Amino acids combine via a specific reaction where:
- The amino group (-NH2) of one amino acid reacts with the carboxyl group (-COOH) of another.
This process forms a peptide bond, and a water molecule is released. By this linking process, amino acids assemble to form long chains called polypeptides. These polypeptides fold into three-dimensional shapes to create functional proteins.
Key Takeaways:
- Basic Structure: All amino acids share a common core structure consisting of a central carbon atom linked to an amino group, a carboxyl group, and a hydrogen atom.
- Side Chain Variance: The side chain (R-group) is what distinguishes each amino acid and imparts its unique chemical properties.
- Peptide Bonds: Amino acids join together via peptide bonds, which form between the amino group of one amino acid and the carboxyl group of another.
- Polypeptide Formation: The sequential linking of amino acids creates polypeptide chains, which ultimately fold into proteins.
| Component | Description |
|---|---|
| Central Carbon | The core atom of each amino acid, bonded to four different groups. |
| Amino Group | (-NH2) Contains a nitrogen atom bonded to two hydrogen atoms, providing basic properties. |
| Carboxyl Group | (-COOH) Contains a carbon atom double bonded to an oxygen atom and single bonded to a hydroxyl group, providing acidic properties. |
| Hydrogen Atom | (-H) A single hydrogen atom directly attached to the central carbon atom. |
| Side Chain/R-Group | A chemical group that varies between each amino acid and determines its properties (e.g., size, charge, hydrophobicity). |
