What elements are made up of proteins


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Structure and structure of proteins

Proteins are made up of 20 different amino acids. Amino acids can be classified according to whether they can be produced by an organism or not. Amino acids that cannot be synthesized by yourself are called essential.
Each amino acid has an identical structure, which is shown in Figure 2.7. An amino acid consists of an amino (NH2) and a carboxyl group (COOH). Both groups are using the -Carbon atom linked together. In addition, a hydrogen atom and a residual group, which is also referred to as a side chain, are bonded to the carbon atom. The various amino acids differ in which groups of atoms are in this side chain. The simplest amino acid is glycine, the remainder of which consists of a hydrogen atom. Amino acids can be linked together to form long chains. If the amino group of one amino acid reacts with the carboxyl group of another amino acid, a peptide bond is formed and water is split off. This creates chains that are called peptides or polypeptides. They are only referred to as proteins when they have a chain length of more than 100 amino acids. However, a protein does not necessarily have to consist of just one amino acid chain. It can also be composed of several chains lying close together. Based on a hundred chain links and 20 different amino acids, there are 20100 different ways to assemble a protein. The enormous number of possible proteins reflects the diverse uses in the organism. The functionality of a protein is determined by its structure, which can be described by several levels of observation. There are four options in total:
Primary structure
The sequence of the amino acids within a protein is called the primary structure.
Secondary structure
The secondary structure reflects the local spatial arrangement of an amino acid sequence. There can be helical structures, which are called -Helix referred to, or unfolded strands, which are called Leaflet are designated, arise.
Tertiary structure
The tertiary structure describes the entire spatial structure of a protein chain. This results from the interrelationships between the side chains of the individual amino acids.
Quaternary structure
If a protein consists of several chains, the entire spatial arrangement is called a quaternary structure.


Next page:eXtensible Markup Language Upwards:Proteins Previous page:Proteins & nbsp content Oliver Krone 2003-04-28