Aminohappojärjestyksen

Aminohappojärjestys, often translated as amino acid sequence, refers to the specific linear order in which amino acids are linked together in a polypeptide chain. This sequence is encoded by the genetic information within a gene. Each gene contains a unique set of codons, which are three-nucleotide sequences that specify which amino acid should be added to the growing polypeptide chain during protein synthesis.

The amino acid sequence is fundamental to a protein's structure and function. Even a single change in the sequence can drastically alter the protein's three-dimensional shape, leading to a loss or modification of its biological activity. This is because the chemical properties of the amino acids, such as their charge, hydrophobicity, and size, dictate how the polypeptide chain folds and interacts with other molecules.

Determining the amino acid sequence of a protein is a crucial step in understanding its role in biological processes. Techniques such as Edman degradation and mass spectrometry are employed for this purpose. Variations in amino acid sequences are also studied in the context of evolution, as they can reveal relationships between different species and the history of life. Furthermore, mutations, which are changes in the DNA sequence, can lead to altered amino acid sequences and are often associated with diseases.