- Source: Secondary amino acid
In organic chemistry, secondary amino acids are amino acids which do not contain the amino group −NH2 but is rather a secondary amine (>NH). Secondary amino acids can be classified to cyclic acids, such as proline, and acyclic N-substituted amino acids.
In nature, proline, hydroxyproline, pipecolic acid and sarcosine are well-known secondary amino acids. Proline is the only proteinogenic secondary amino acids. Other secondary amino acids are non-proteinogenic amino acids. In protein, hydroxyproline is incorporated into protein by hydroxylation of proline. Pipecolic acid, a heavier analog of proline, is found in efrapeptin. Sarcosine is a N-methylized glycine so its methyl group is used in many biochemical reactions. Azetidine-2-carboxylic acid, which is a smaller homolog of proline in plants.
Properties
Proline and its higher homolog pipecolic acid affect the secondary structure of protein. D-alpha-amino acid - L-alpha-amino acid sequence can induce beta hairpin. It suggested that acyclic secondary amino acids are more flexible than cyclic secondary amino acids in protein by replacement of pipecolic acid by N-methyl-L-alanine in efrapeptin C.
Ninhydrin tests of proline and hydroxyproline give yellow results.
In enzymology, a N-methyl-L-amino-acid oxidase is an oxidase of a subtype of secondary amino acids.
See also
Imino acid
Imidic acid
Secondary amine
References
External links
Kata Kunci Pencarian:
- Protein
- Enzim
- Achmad Syahrani
- Periodinana Dess–Martin
- Bakteri
- Hati
- Zat antinutrisi pada pakan
- Diisobutilaluminium hidrida
- Triptofol
- Botani
- Secondary amino acid
- Non-proteinogenic amino acids
- Aromatic amino acid
- Amino acid
- Strecker amino acid synthesis
- Proline
- Amino acid replacement
- Alanine
- Amine
- Imino acid
