ornithine
Học thuậtThân thiện
Definition
Noun: * An amino acid that is not a building block of proteins but plays a crucial role in the urea cycle, a metabolic process that converts toxic ammonia into urea for excretion from the body.
Usage
- ornithine is an uncountable noun used primarily in biochemical and medical contexts.
- It is often discussed in relation to metabolic pathways, liver function, and detoxification processes.
Examples
- The enzyme ornithine transcarbamylase is essential for the ornithine cycle.
- A deficiency in ornithine metabolism can lead to hyperammonemia.
- Ornithine is a central intermediate in the conversion of ammonia to urea.
Advanced Usage
- Ornithine Cycle: Also known as the urea cycle, it is the metabolic pathway where ornithine is a key carrier molecule.
- Ornithine Decarboxylase: An enzyme that converts ornithine into putrescine, initiating polyamine synthesis, which is important for cell growth.
Variants and Related Words
- L-ornithine: The specific, naturally occurring form (isomer) of ornithine involved in human biochemistry.
Synonyms
- There are no direct common synonyms for this specific biochemical compound. It may be described as a non-proteinogenic amino acid or a urea cycle intermediate.
Related Phrases/Compounds
- Ornithine transcarbamylase (OTC): A liver enzyme.
- Ornithine decarboxylase (ODC): An enzyme in polyamine synthesis.
Noun
- an amino acid that does not occur in proteins but is important in the formation of urea