Cysteine

Definition

Cysteine is a sulfur-containing amino acid that plays a crucial role in protein synthesis and detoxification processes in the body. It is considered semi-essential because it can be synthesized from methionine, another amino acid.

5 Must Know Facts For Your Next Test

1. Cysteine is important for synthesizing glutathione, an antioxidant vital for protecting renal cells from oxidative stress.
2. High levels of cysteine can lead to kidney stones due to its sulfur content forming insoluble compounds.
3. Patients with chronic kidney disease may have altered cysteine metabolism, affecting their nutritional requirements.
4. Cysteine supplementation must be carefully monitored in patients with renal impairment to prevent toxicity.
5. Dietary sources of cysteine include poultry, eggs, dairy products, and some plant-based foods like broccoli and Brussels sprouts.

Review Questions

• Why is cysteine important for renal health?
• What are potential risks associated with high levels of cysteine in individuals with renal conditions?
• Name three dietary sources rich in cysteine.

Related terms

Methionine:

An essential amino acid required for protein synthesis and precursor to cysteine.

Glutathione: A powerful antioxidant synthesized from cysteine that protects cells from oxidative damage.

Chronic Kidney Disease (CKD): A long-term condition characterized by gradual loss of kidney function over time, impacting nutrient metabolism including that of amino acids like cysteine.