Proline
From Freepedia
| Proline | |
|---|---|
| Systematic name | (S)-Pyrrolidine- 2-carboxylic acid |
| Abbreviations | Pro P |
| Chemical formula | C5H9NO2 |
| Molecular mass | 115.13 g mol-1 |
| Melting point | 221 °C |
| Density | ? g cm-3 |
| Isoelectric point | 6.30 |
| pKa | 1.95 10.47 |
| CAS number | [147-85-3] |
| EINECS number | 205-702-2 |
| SMILES | C1CCNC1C(=O)O |
| Image:Proline.png | |
| Disclaimer and references | |
L-Proline is one of the twenty proteinogenic amino acids that are used by living organisms as building blocks of proteins. It is the only amino acid that contains a secondary amino group and forms tertiary peptide bonds. Proline is therefore sometimes incorrectly called an imino acid.
Proline is a non-polar amino acid. It proteins it does not have a hydrogen on the amide group and can therefore not act as a hydrogen bond donor. Proline can act as a structural disruptor for (α) helices, and as a turning point in β sheets. Multiple prolines and/or hydroxyprolines in a row can create a proline helix; this is the predominant structure in collagen. Sequences of proline and 1-aminoisobutyric acid (Aib) form a helical turn structure.
Proline in biosynthetically derived from the amino acid L-glutamate and its direct precursor is the real imino acid (S)-Δ1-pyrroline-5-carboxylate (P5C).
Proline and its derivatives are often used as asymetric catalysts in organic reactions. The CBS reduction or proline catalysed aldol condensation are prominent examples.
External links
| Alanine | Arginine | Asparagine | Aspartic acid | Cysteine | Glutamic acid | Glutamine | Glycine | Histidine | Isoleucine | Leucine | Lysine | Methionine | Phenylalanine | Proline | Serine | Threonine | Tryptophan | Tyrosine | Valine |
| Essential amino acid | Protein | Peptide | Genetic code |
