hydroxyproline
Học thuậtThân thiện
Definition
Noun: A crystalline, non-essential amino acid derived from the modification of the amino acid proline. It is a major component of collagen and gelatin, where it is crucial for stabilizing the triple-helix structure of collagen molecules, providing strength to connective tissues like skin, bones, and tendons.
Usage and Examples
- As a subject:
- As an object:
- With a preposition:
Advanced Usage
- In Biochemistry/Medicine: Hydroxyproline is a biomarker. Its urinary excretion level is often measured clinically to assess the rate of collagen breakdown in conditions like bone disorders (e.g., Paget's disease) or metastatic bone disease.
- Elevated urinary hydroxyproline can indicate increased bone resorption.
Variants and Related Words
- Hydroxyprolinemia (n): A rare metabolic disorder characterized by an excess of hydroxyproline in the blood and urine.
- Proline (n): The precursor amino acid that is hydroxylated (has an -OH group added) to form hydroxyproline.
Synonyms and Related Terms
- 4-Hydroxyproline (n): The specific, most common isomer found in collagen.
- Hyp (n): A common three-letter abbreviation used in biochemistry and sequence notation (e.g., in describing collagen sequences like Gly-X-Hyp, where X is another amino acid).
Notes on Meaning
- Key Distinction: Unlike standard amino acids, hydroxyproline is not coded for by DNA in the genetic code. Instead, it is formed by a post-translational modification, where proline residues in a collagen chain are hydroxylated by enzymes (prolyl hydroxylase) after the protein chain is synthesized. This process requires vitamin C.
Noun
- a crystalline amino acid obtained from gelatin or collagen