THE MEDICAL IMPORTANCE OF SULFUR-CONTAINING Α-AMINO ACIDS

Аннотация

This article provides information about amino acids that are highly important for the organism. It mainly covers the medical significance of sulfur-containing α-amino acids, their properties, processes occurring through them, and their role and significance in the body. Additionally, the biological important reactions of α-amino acids are discussed. Foods that contain both exchangeable and non-exchangeable α-amino acids, as well as the changes that occurinthehuman bodydueto theirdeficiency, are also analyzed. Keywords: Sulfur-containing amino acids, cysteine, methionine, taurine, antioxidant properties, immunesystem strengthening, cardiovascular health, cystine. Amino acids form the basis of all plant and animal proteins. They exist in the form of peptides and proteins, or combined with other compounds. Amino acids can be viewed as substances in which the hydrogen atom in the carboxyl group radical is replaced by an amino group. Amino acids, as heterofunctional compounds, contain two different functional groups—amino and carboxyl groups—simultaneously. Aminoacids are classified according tothe natureof theirradical: 1. Aliphatic; 2. Aromatic; 3. Heterocyclic. Amino acids with an aliphatic radical include alanine, valine, and leucine. Aromatic and heterocyclic α-amino acids have an aromatic or heterocyclic ring, which is separated from the mainfragment oftheα-amino acid bya singlemethylene group. There are also amino acids that retain other functional groups in their aliphatic radical. These include: 1. Serineandthreonine, which retain an OH group; 2. Cystine, cysteine, and methionine, which retain S-S,-SH, and-S-CHgroups; 3. Asparagine andglutamine acids, which retain an additional -COOH group; http://www.internationaljournal.co.in/index.php/jasass 199 Volume15 Issue02, February2025 Impact factor: 2019: 4.679 2020: 5.015 2021: 5.436, 2022: 5.242, 2023: 6.995, 2024 7.75 4. Lysine, which retains an additional -NH group; 5. Asparagine andglutamine, which retain an amidegroup. Amino acids can be classified as either exchangeable or non-exchangeable based on their ability to be synthesized in the organism. The number of essential amino acids in proteins is 20. Some of these amino acids are not synthesized in the body and are called non-exchangeable amino acids. Non-exchangeable amino acids enter thebody through dietary intake. These include valine, leucine, isoleucine, threonine, lysine, methionine, phenylalanine, and tryptophan. Amino acids synthesized in the body are called exchangeable amino acids. These include glycine, alanine, serine, asparagine, glutamic acid, cysteine, tyrosine, histidine, and proline. The 20 amino acids present in human proteins differ by their R group. For example, alanine has a methyl group in place of the R radical. If the positive and negative charges in an amino acid are balanced, the overall charge will be "0," corresponding to a specific pH value known as the isoelectric point (pI). The R group of amino acids determines their properties in aqueous solutions. Non-polar amino acids have R groups that are hydrogen, alkyl, or aromatic, making them hydrophobic (water-repellent), while polar amino acids have R groups that can interact with water, making themhydrophilic (water-attracting). Sulfur-containing amino acids, such as cysteine, methionine, and taurine, play a significant role in various physiological processes in the body. For example, cysteine can form disulfide bonds thatstabilize protein structures. TheMedical Importance ofSulfur-Containingα-Amino Acids: Cystinuria: Cystine is primarily excreted through urine. If cystine metabolism is disrupted, it can accumulate in the urine, leading to the formation ofcystine stones, known as cystine lithiasis. Thiscan cause kidney problems, includingpain, difficulty urinating, and kidneyfailure. Antioxidant Properties: Cystine acts as an antioxidant and helps neutralize free radicals and toxinsin thebody. http://www.internationaljournal.co.in/index.php/jasass 200 Volume15 Issue02, February2025 Impact factor: 2019: 4.679 2020: 5.015 2021: 5.436, 2022: 5.242, 2023: 6.995, 2024 7.75 Collagen Synthesis: Cystine is involved in collagen production, which is essential for skin, hair, nails,and connective tissues. Cystinedeficiency can affect thehealth of thesetissues. Medical Use: Cystine is used in certain medicinal supplements to reduce oxidative stress, strengthen the immune system, and aid in the healing of damaged tissues. Sulfur-containing α- amino acids, such as cysteine, methionine, and taurine, are crucial in various physiological processes, including detoxification, antioxidant protection, immune system strengthening, and supporting cardiovascular and neurological health. Their medicinal significance is multifaceted andcontributes to physical and psychological health. TheirRole andImportance inthe Body: Detoxification and Antioxidant Properties: Cysteine and taurine act as antioxidants. Cysteine, in particular, is a major component in