CYSTATHIONINE Meaning and
Definition
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Cystathionine is a naturally occurring amino acid that plays a crucial role in various metabolic processes within the human body. It is formed through the condensation of homocysteine and serine, with the help of the enzyme cystathionine beta-synthase (CBS).
As a fundamental component in the transsulfuration pathway, cystathionine acts as an intermediary compound in the conversion of methionine (an essential amino acid) into cysteine. This metabolic pathway is vital for the generation of glutathione, a powerful antioxidant that protects cells from oxidative damage.
Beyond its role in sulfur metabolism, cystathionine also serves as a precursor for the synthesis of hydrogen sulfide (H2S), an endogenously produced gasotransmitter involved in numerous physiological functions. H2S has been implicated in regulating blood vessel dilation, inflammation, neurotransmission, and mitochondrial function.
Furthermore, cystathionine has attracted scientific interest due to its potential connection with certain genetic disorders. Mutations or deficiencies in the CBS enzyme can lead to an accumulation of homocysteine, which is associated with conditions like homocystinuria or hyperhomocysteinemia. These disorders can manifest with various clinical symptoms, including ocular abnormalities, intellectual disabilities, cardiovascular complications, and thrombosis.
In summary, cystathionine is an amino acid derivative that is crucial for sulfur metabolism, glutathione synthesis, and the generation of hydrogen sulfide. Its role in various physiological processes and its association with certain genetic disorders make cystathionine a subject of scientific research and clinical interest.
Etymology of CYSTATHIONINE
The word "cystathionine" is derived from the combination of two components: "cysteine" and "homocysteine".
"Cysteine" is derived from the Latin word "cysteinum", which in turn comes from the Greek "κύστης" (kustēs), meaning "bladder" or "sac". The name refers to the presence of a disulfide bond, which forms a cystine molecule resembling a bladder or sac-like structure.
"Homocysteine" is composed of the prefix "homo-", meaning "same" or "similar", and "cysteine", referring to its structural similarity to cysteine.
When these two components are combined, they form "cystathionine", representing the union of cysteine and homocysteine in a molecule.
