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Hypermethioninemia
Hypermethioninemia is an excess of the amino acid methionine, in the blood. This condition can occur when methionine is not broken down properly in the body. Presentation Genetics Hypermethioninemia can have different inheritance patterns. This condition is usually inherited in an autosomal recessive pattern, which means two copies of the gene in each cell are altered. Most often, the parents of an individual with an autosomal recessive disorder each carry one copy of the altered gene but do not show signs and symptoms of the disorder. Hypermethioninemia is occasionally inherited in an autosomal dominant pattern, which means one copy of the altered gene in each cell is sufficient to cause the disorder. In these cases, an affected person usually has one parent with the condition. Pathophysiology Inherited hypermethioninemia that is not associated with other metabolic disorders can be caused by shortages in the enzymes that break down methionine. These enzymes are produced from t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Amino Acid Metabolism Disorders
Inborn errors of amino acid metabolism are metabolic disorders which impair the synthesis and degradation of amino acids. Types *Alkaptonuria *Aspartylglucosaminuria *Branched-chain keto acid dehydrogenase kinase deficiency *Methylmalonic acidemia *Maple syrup urine disease *Homocystinuria *Tyrosinemia *Trimethylaminuria *Hartnup disease *Biotinidase deficiency *Ornithine carbamoyltransferase deficiency *Carbamoyl-phosphate synthase I deficiency disease *Citrullinemia *Hyperargininemia *Hyperhomocysteinemia *Hypermethioninemia *Hyperlysinemias *Nonketotic hyperglycinemia *Propionic acidemia *Hyperprolinemia Amino acid transport disorders *Cystinuria *Dicarboxylic aminoaciduria *Hartnup disease Amino acid storage disorders *Glutaric acidemia type 2 Glutaric acidemia type 2 is an autosomal recessive metabolic disorder that is characterised by defects in the ability of the body to use proteins and fats for energy. Incompletely processed proteins and fats can build up, leading to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Methionine
Methionine (symbol Met or M) () is an essential amino acid in humans. As the precursor of other amino acids such as cysteine and taurine, versatile compounds such as SAM-e, and the important antioxidant glutathione, methionine plays a critical role in the metabolism and health of many species, including humans. It is encoded by the codon AUG. Methionine is also an important part of angiogenesis, the growth of new blood vessels. Supplementation may benefit those suffering from copper poisoning. Overconsumption of methionine, the methyl group donor in DNA methylation, is related to cancer growth in a number of studies. Methionine was first isolated in 1921 by John Howard Mueller. Biochemical details Methionine (abbreviated as Met or M; encoded by the codon AUG) is an α-amino acid that is used in the biosynthesis of proteins. It contains a carboxyl group (which is in the deprotonated −COO− form under biological pH conditions), an amino group (which is in the protonated fo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Homocysteine
Homocysteine is a non-proteinogenic α-amino acid. It is a homologue of the amino acid cysteine, differing by an additional methylene bridge (-CH2-). It is biosynthesized from methionine by the removal of its terminal Cε methyl group. In the body, homocysteine can be recycled into methionine or converted into cysteine with the aid of certain B-vitamins. High levels of homocysteine in the blood (hyperhomocysteinemia) is regarded as a marker of cardiovascular disease, likely working through atherogenesis, which can result in ischemic injury. Therefore, hyperhomocysteinemia is a possible risk factor for coronary artery disease. Coronary artery disease occurs when an atherosclerotic plaque blocks blood flow to the coronary arteries, which supply the heart with oxygenated blood. Hyperhomocysteinemia has been correlated with the occurrence of blood clots, heart attacks, and strokes, although it is unclear whether hyperhomocysteinemia is an independent risk factor for these conditi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Liver Disease
Liver disease, or hepatic disease, is any of many diseases of the liver. If long-lasting it is termed chronic liver disease. Although the diseases differ in detail, liver diseases often have features in common. Signs and symptoms Some of the signs and symptoms of a liver disease are the following: * Jaundice * Confusion and altered consciousness caused by hepatic encephalopathy. * Thrombocytopenia and coagulopathy. * Risk of bleeding symptoms particularly taking place in gastrointestinal tract Liver diseases File:Ground glass hepatocytes high mag cropped 2.jpg, Ground glass hepatocytes File:Primary biliary cirrhosis intermed mag much cropping.jpg, Primary biliary cirrhosis File:Buddchiari2.PNG, Budd-chiari syndrome File:Non-alcoholic_fatty_liver_disease1.jpg, Micrograph of non-alcoholic fatty liver disease There are more than a hundred different liver diseases. Some of the most common are: * Fascioliasis, a parasitic infection of liver caused by a liver fluke of the genus '' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Galactosemia
Galactosemia (British galactosaemia, from Greek γαλακτόζη + αίμα, meaning galactose + blood, accumulation of galactose in blood) is a rare genetic metabolic disorder that affects an individual's ability to metabolize the sugar galactose properly. Galactosemia follows an autosomal recessive mode of inheritance that confers a deficiency in an enzyme responsible for adequate galactose degradation. Friedrich Goppert (1870–1927), a German physician, first described the disease in 1917, with its cause as a defect in galactose metabolism being identified by a group led by Herman Kalckar in 1956. Galactosemia was the second disorder found to be detectable through newborn screening methods by Robert Guthrie. Its incidence is about 1 per 60,000 births for people of European ancestry. In other populations the incidence rate differs. Galactosaemia is about one hundred times more common (1:480 births) in the Irish Traveller population. Symptoms Adults Infants Infan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tyrosinemia
Tyrosinemia or tyrosinaemia is an error of metabolism, usually inborn, in which the body cannot effectively break down the amino acid tyrosine. Symptoms of untreated tyrosinemia include liver and kidney disturbances. Without treatment, tyrosinemia leads to liver failure. Today, tyrosinemia is increasingly detected on newborn screening tests before any symptoms appear. With early and lifelong management involving a low-protein diet, special protein formula, and sometimes medication, people with tyrosinemia develop normally, are healthy, and live normal lives. Cause All tyrosinemias result from dysfunction of various genes in the phenylalanine and tyrosine catabolic pathway, and are inherited in an autosomal-recessive pattern. Type I tyrosinemia results from a mutation in the ''FAH'' gene, which encodes the enzyme fumarylacetoacetase. As a result of ''FAH'' deficiency, the substrate fumarylacetoacetate can accumulate in proximal renal tubular cells and hepatocytes, resulting in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Homocystinuria
Homocystinuria or HCU is an inherited disorder of the metabolism of the amino acid methionine due to a deficiency of cystathionine beta synthase or methionine synthase. It is an inherited autosomal recessive trait, which means a child needs to inherit a copy of the defective gene from both parents to be affected. Symptoms of homocystinuria can also be caused by a deficiency of vitamins B6, B12, or folate. Signs and symptoms This defect leads to a multi-systemic disorder of the connective tissue, muscles, central nervous system (CNS), and cardiovascular system. Homocystinuria represents a group of hereditary metabolic disorders characterized by an accumulation of the amino acid homocysteine in the serum and an increased excretion of homocysteine in the urine. Infants appear to be normal and early symptoms, if any are present, are vague. Signs and symptoms of homocystinuria that may be seen include the following: Cause It is usually caused by the deficiency of the enzyme cystathi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mental Retardation
Intellectual disability (ID), also known as general learning disability in the United Kingdom and formerly mental retardation,Rosa's Law, Pub. L. 111-256124 Stat. 2643(2010). is a generalized neurodevelopmental disorder characterized by significantly impaired intellectual and adaptive functioning. It is defined by an IQ under 70, in addition to deficits in two or more adaptive behaviors that affect everyday, general living. Intellectual functions are defined under DSM-V as reasoning, problem‑solving, planning, abstract thinking, judgment, academic learning, and learning from instruction and experience, and practical understanding confirmed by both clinical assessment and standardized tests. Adaptive behavior is defined in terms of conceptual, social, and practical skills involving tasks performed by people in their everyday lives. Intellectual disability is subdivided into syndromic intellectual disability, in which intellectual deficits associated with other medical and beh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cysteine
Cysteine (symbol Cys or C; ) is a semiessential proteinogenic amino acid with the formula . The thiol side chain in cysteine often participates in enzymatic reactions as a nucleophile. When present as a deprotonated catalytic residue, sometimes the symbol Cyz is used. The deprotonated form can generally be described by the symbol Cym as well. The thiol is susceptible to oxidation to give the disulfide derivative cystine, which serves an important structural role in many proteins. In this case, the symbol Cyx is sometimes used. When used as a food additive, it has the E number E920. Cysteine is encoded by the codons UGU and UGC. The sulfur-containing amino acids cysteine and methionine are more easily oxidized than the other amino acids. Structure Like other amino acids (not as a residue of a protein), cysteine exists as a zwitterion. Cysteine has chirality in the older / notation based on homology to - and -glyceraldehyde. In the newer ''R''/''S'' system of designating chi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adenosylhomocysteinase
Adenosylhomocysteinase (, ''S''-adenosylhomocysteine synthase, ''S''-adenosylhomocysteine hydrolase, adenosylhomocysteine hydrolase, ''S''-adenosylhomocysteinase, SAHase, AdoHcyase) is an enzyme that converts ''S''-adenosylhomocysteine to homocysteine and adenosine. This enzyme catalyses the following chemical reaction : ''S''-adenosyl-L-homocysteine + H2O L-homocysteine + adenosine Adenosine ( symbol A) is an organic compound that occurs widely in nature in the form of diverse derivatives. The molecule consists of an adenine attached to a ribose via a β-N9-glycosidic bond. Adenosine is one of the four nucleoside building ... The enzyme contains one tightly bound NAD+ per subunit. The mechanism involves dehydrogenative oxidation of the 3'-OH of the ribose. The resulting ketone is susceptible to α-deprotonation. The resulting carbanion eliminates thiolate. The a,b-unsaturated ketone is then hydrated, and the ketone is reduced by the NADH. References External link ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Medical Genetics
Medical genetics is the branch tics in that human genetics is a field of scientific research that may or may not apply to medicine, while medical genetics refers to the application of genetics to medical care. For example, research on the causes and inheritance of genetic disorders would be considered within both human genetics and medical genetics, while the diagnosis, management, and counselling people with genetic disorders would be considered part of medical genetics. In contrast, the study of typically non-medical phenotypes such as the genetics of eye color would be considered part of human genetics, but not necessarily relevant to medical genetics (except in situations such as albinism). ''Genetic medicine'' is a newer term for medical genetics and incorporates areas such as gene therapy, personalized medicine, and the rapidly emerging new medical specialty, predictive medicine. Scope Medical genetics encompasses many different areas, including clinical practice of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glycine N-methyltransferase
In enzymology, a glycine N-methyltransferase () is an enzyme that catalyzes the chemical reaction :S-adenosyl-L-methionine + glycine \rightleftharpoons S-adenosyl-L-homocysteine + sarcosine Thus, the substrates of this enzyme are S-adenosyl methionine and glycine, whereas its two products are S-adenosylhomocysteine and sarcosine. Glycine N-methyltransferase belongs to the family of methyltransferase enzymes. The systematic name A systematic name is a name given in a systematic way to one unique group, organism, object or chemical substance, out of a specific population or collection. Systematic names are usually part of a nomenclature. A semisystematic name or semitrivial ... of this enzyme class is S-adenosyl-L-methionine:glycine N-methyltransferase. Other names in common use include glycine methyltransferase, S-adenosyl-L-methionine:glycine methyltransferase, and GNMT. This family of enzymes participates in the metabolism of multiple amino acids. References * * * * * ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
