Histidine ball and stick model spinning. Histidine (symbol His or H) [2] is an essential amino acid that is used in the biosynthesis of proteins.It contains an α-amino group (which is in the protonated –NH 3 + form under biological conditions), a carboxylic acid group (which is in the deprotonated –COO − form under biological conditions), and an imidazole side chain (which is …

2023年11月22日 · L-Histidine - structure, chemical names, physical and chemical properties, function

Learn more about HISTIDINE uses, effectiveness, possible side effects, interactions, dosage, user ratings and products that contain HISTIDINE.

2019年6月14日 · 6. Can Help Defend Against Allergies and Infections. When used with zinc, there’s evidence that histidine can help protect against colds and reduce the duration that colds last. Histidine supplementation may also reduce the duration of viral or bacterial infections.

2024年9月9日 · Because L-histidine is an essential amino acid, the body doesn’t make it naturally. Therefore, it must be consumed in food. Some people also take supplements to increase their levels of L-histidine, believing that the boost can prevent heart disease or improve several conditions, such as rheumatoid arthritis.

2023年7月30日 · Histidine is a nutritionally essential amino acid precursor for several hormones (eg, thyrotropin-releasing hormone) and critical metabolites affecting renal function, neurotransmission, gastric secretion, and the immune system. Histidine's unique acid/base properties make it a versatile catalytic residue in many enzymes and for those proteins and …

L-histidine (HIS) is an essential amino acid with unique roles in proton buffering, metal ion chelation, scavenging of reactive oxygen and nitrogen species, erythropoiesis, and the histaminergic system. Several HIS-rich proteins (e.g., ...

Catabolic pathways of histidine [].Urocanic acid has a protective role against harmful effects of ultraviolet rays on the skin. It is metabolized in the liver to 4, 5-dihydri-4-oxo-5-imidazolepropanoic acid by urocanate hydratase, and is then converted to formimino-glutamate (FIGLU) and N 5-formimino-tetrahydro-folate.In epiderma, urocanate hydratase is not present, and urocanic …

Since the actions of supplemental L-histidine are unclear, any postulated mechanism is entirely speculative. However, some facts are known about L-histidine and some of its metabolites, such as histamine and trans-urocanic acid, which suggest that supplemental L-histidine may one day be shown to have immunomodulatory and/or antioxidant activities.. Low free histidine has …

Histidine, an amino acid obtainable by hydrolysis of many proteins. A particularly rich source, hemoglobin (the oxygen-carrying pigment of red blood cells) yields about 8.5 percent by weight of histidine. First isolated in 1896 from various proteins, histidine is one of several so-called essential