Cystine is a sulfur-containing amino acid formed from two cysteine molecules. It is a stable form of cysteine and can be synthesized in the body. Cystine is found in various food sources and is involved in protein construction and cellular functions. Abnormal cystine metabolism can lead to disorders such as cysturia, cystinosis, and Fanconi syndrome. Cystine is also present in various proteins and is involved in detoxification processes.
Cystine is a naturally occurring sulfur-containing amino acid derived from cysteine, a related amino acid. Both are among the 20 amino acids involved in the construction of plant and animal proteins and in the control of cellular functions by catalyzing most of the chemical reactions that occur in living cells. Cystine is a dimeric amino acid formed from the oxidation of two simpler and identical cysteine molecules, whose sulfur atoms have joined to form a disulfide bridge. It is known as a “dimeric” molecule and is a chemically stable form of cysteine. It is a tasteless organic compound with the molecular formula C6H12N2O4 S2.
William Hyde Wollaston identified cystine in 1810. It went virtually undetected until it was isolated from a cow’s horn in 1899. Then it was finally recognized as a component of protein.
Both cystine and cysteine are classified as non-essential amino acids. They can be synthesized within the body, so it is not essential that they be obtained from food. They are derived from the same sources, provide identical nutritional benefits, and are required by the human body for basic health and vitality. One food source that is naturally rich in cystine/cysteine is unpasteurized whey protein. Other food sources include garlic, onion, fish, liver, eggs, sesame seeds, and other seeds.
There are several inherited diseases and disorders associated with the abnormal metabolism, transport, and storage of this amino acid. One of these disorders is cysturia, a metabolic defect characterized by abnormal movement of cystine and other amino acids in the kidneys and intestines. Cystine is produced as a natural deposit in the urine, but excessive amounts of cystine accumulate and do not dissolve in the urine. This can cause kidney stones, as well as deposits in the ureters and bladder.
Cystinosis is a rare genetic disorder that occurs in young children. It is characterized by abnormal cystine metabolism and the accumulation of cystine crystals in cell tissues. These crystals can negatively affect many systems in the body. The kidneys and eyes tend to suffer the most damage, and retinopathy and short statue are hallmarks of the disorder.
Another cystine-related disorder occurs when cell function in the renal tubules is impaired. This can lead to Fanconi syndrome, which can also be caused by drugs or heavy metals. In Fanconi syndrome, certain substances that are normally absorbed into the bloodstream by the kidneys are released into the urine.
A variety of proteins contain cystine, including animal feathers and hooves. Cysteine, in particular, is present in hair, nails, and skin as alpha-keratin, an insoluble fibrous protein. It is abundant in skeletal and connective tissues. Cysteine and its dimeric molecule cystine are also involved in major detoxification processes in the body.
Protect your devices with Threat Protection by NordVPN
