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L-glutamic Acid Decarboxylase
Glutamate decarboxylase or glutamic acid decarboxylase (GAD) is an enzyme that catalyzes the decarboxylation of glutamate to gamma-aminobutyric acid (GABA) and carbon dioxide (). GAD uses pyridoxal-phosphate (PLP) as a cofactor. The reaction proceeds as follows: : In mammals, GAD exists in two isoforms with molecular weights of 67 and 65 kDa (GAD67 and GAD65), which are encoded by two different genes on different chromosomes (''GAD1'' and ''GAD2'' genes, chromosomes 2 and 10 in humans, respectively). GAD67 and GAD65 are expressed in the brain where GABA is used as a neurotransmitter, and they are also expressed in the insulin-producing β-cells of the pancreas, in varying ratios depending upon the species. Together, these two enzymes maintain the major physiological supply of GABA in mammals, though it may also be synthesized from putrescine in the enteric nervous system, brain, and elsewhere by the actions of diamine oxidase and aldehyde dehydrogenase 1a1. Several trunc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
GAD1
Glutamate decarboxylase 1 (brain, 67kDa) (GAD67), also known as GAD1, is a human gene. This gene encodes one of several forms of glutamic acid decarboxylase, identified as a major autoantigen in insulin-dependent diabetes. The enzyme encoded is responsible for catalyzing the production of gamma-aminobutyric acid from L-glutamic acid. A pathogenic role for this enzyme has been identified in the human pancreas since it has been identified as an autoantigen and an autoreactive T cell target in insulin-dependent diabetes. This gene may also play a role in the stiff man syndrome. Deficiency in this enzyme has been shown to lead to pyridoxine dependency with seizures. Alternative splicing Alternative splicing, alternative RNA splicing, or differential splicing, is an alternative RNA splicing, splicing process during gene expression that allows a single gene to produce different splice variants. For example, some exons of a gene ma ... of this gene results in two products, the pre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pancreas
The pancreas (plural pancreases, or pancreata) is an Organ (anatomy), organ of the Digestion, digestive system and endocrine system of vertebrates. In humans, it is located in the abdominal cavity, abdomen behind the stomach and functions as a gland. The pancreas is a mixed or heterocrine gland, i.e., it has both an endocrine and a digestive exocrine function. Ninety-nine percent of the pancreas is exocrine and 1% is endocrine. As an endocrine gland, it functions mostly to regulate blood sugar levels, secreting the hormones insulin, glucagon, somatostatin and pancreatic polypeptide. As a part of the digestive system, it functions as an exocrine gland secreting pancreatic juice into the duodenum through the pancreatic duct. This juice contains bicarbonate, which neutralizes acid entering the duodenum from the stomach; and digestive enzymes, which break down carbohydrates, proteins and lipids, fats in food entering the duodenum from the stomach. Inflammation of the pancreas is kno ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dendrodendritic Synapse
Dendrodendritic synapses are connections between the dendrites of two different neurons. This is in contrast to the more common axodendritic synapse (chemical synapse) where the axon sends signals and the dendrite receives them. Dendrodendritic synapses are activated in a similar fashion to axodendritic synapses in respects to using a chemical synapse. An incoming action potential permits the release of neurotransmitters to propagate the signal to the post synaptic cell. There is evidence that these synapses are bi-directional, in that either dendrite can signal at that synapse. Ordinarily, one of the dendrites will display inhibitory effects while the other will display excitatory effects. The actual signaling mechanism utilizes Na+ and Ca2+ pumps in a similar manner to those found in axodendritic synapses. History In 1966 Wilfrid Rall, Gordon Shepherd, Thomas Reese, and Milton Brightman found a novel pathway, dendrites that signaled to dendrites. While studying the mammalian ol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Attention Deficit Hyperactivity Disorder
Attention deficit hyperactivity disorder (ADHD) is a neurodevelopmental disorder characterised by symptoms of inattention, hyperactivity, impulsivity, and emotional dysregulation that are excessive and pervasive, impairing in multiple contexts, and Developmental psychology, developmentally inappropriate. ADHD symptoms arise from executive dysfunction. Impairments resulting from deficits in self-regulation such as time management, Cognitive inhibition, inhibition, task initiation, and sustained attention can include poor professional performance, relationship difficulties, and numerous health risks, collectively predisposing to a diminished Quality of life (healthcare), quality of life and a reduction in life expectancy. As a consequence, the disorder costs society hundreds of billions of US dollars each year, worldwide. It is associated with other mental disorders as well as non-psychiatric disorders, which can cause additional impairment. While ADHD involves a lack of su ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pyridoxal Phosphate
Pyridoxal phosphate (PLP, pyridoxal 5'-phosphate, P5P), the active form of vitamin B6, is a coenzyme in a variety of enzymatic reactions. The International Union of Biochemistry and Molecular Biology has catalogued more than 140 PLP-dependent activities, corresponding to ~4% of all classified activities. The versatility of PLP arises from its ability to covalently bind the substrate, and then to act as an electrophilic catalyst, thereby stabilizing different types of carbanionic reaction intermediates. Role as a coenzyme PLP acts as a coenzyme in all transamination reactions, and in certain decarboxylation, deamination, and racemization reactions of amino acids. The aldehyde group of PLP forms a Schiff-base linkage (internal aldimine) with the ε-amino group of a specific lysine group of the aminotransferase enzyme. The α-amino group of the amino acid substrate displaces the ε-amino group of the active-site lysine residue in a process known as transaldimination. The r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Escherichia Coli
''Escherichia coli'' ( )Wells, J. C. (2000) Longman Pronunciation Dictionary. Harlow ngland Pearson Education Ltd. is a gram-negative, facultative anaerobic, rod-shaped, coliform bacterium of the genus '' Escherichia'' that is commonly found in the lower intestine of warm-blooded organisms. Most ''E. coli'' strains are part of the normal microbiota of the gut, where they constitute about 0.1%, along with other facultative anaerobes. These bacteria are mostly harmless or even beneficial to humans. For example, some strains of ''E. coli'' benefit their hosts by producing vitamin K2 or by preventing the colonization of the intestine by harmful pathogenic bacteria. These mutually beneficial relationships between ''E. coli'' and humans are a type of mutualistic biological relationship—where both the humans and the ''E. coli'' are benefitting each other. ''E. coli'' is expelled into the environment within fecal matter. The bacterium grows massi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
2-keto-4-pentenoic Acid
2-Oxopent-4-enoic acid (2-oxopent-4-enoate) is formed by the dehydration of 4-hydroxy-2-oxopentanoate by 2-oxopent-4-enoate hydratase or by the hydrolysis of 2-hydroxymuconate semialdehyde by 2-hydroxymuconate-semialdehyde hydrolase. References External links Oxopentenoate biocyc.org Alpha-keto acids {{ketone-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
GAD67 Active Site
Glutamate decarboxylase or glutamic acid decarboxylase (GAD) is an enzyme that catalyzes the Decarboxylation#Decarboxylation of amino acids, decarboxylation of glutamate to gamma-aminobutyric acid (GABA) and carbon dioxide (). GAD uses pyridoxal-phosphate (PLP) as a cofactor (biochemistry), cofactor. The reaction proceeds as follows: : In mammals, GAD exists in two isoforms with molecular weights of 67 and 65 Dalton (unit), kDa (GAD67 and GAD65), which are encoded by two different genes on different chromosomes (''GAD1'' and ''GAD2'' genes, Chromosome 2, chromosomes 2 and Chromosome 10, 10 in humans, respectively). GAD67 and GAD65 are expressed in the brain where GABA is used as a neurotransmitter, and they are also expressed in the insulin-producing beta cell, β-cells of the pancreas, in varying ratios depending upon the species. Together, these two enzymes maintain the major physiological supply of GABA in mammals, though it may also be synthesized from putrescine in the ent ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polypeptide
Peptides are short chains of amino acids linked by peptide bonds. A polypeptide is a longer, continuous, unbranched peptide chain. Polypeptides that have a molecular mass of 10,000 Da or more are called proteins. Chains of fewer than twenty amino acids are called oligopeptides, and include dipeptides, tripeptides, and tetrapeptides. Peptides fall under the broad chemical classes of biological polymers and oligomers, alongside nucleic acids, oligosaccharides, polysaccharides, and others. Proteins consist of one or more polypeptides arranged in a biologically functional way, often bound to ligands such as coenzymes and cofactors, to another protein or other macromolecule such as DNA or RNA, or to complex macromolecular assemblies. Amino acids that have been incorporated into peptides are termed residues. A water molecule is released during formation of each amide bond.. All peptides except cyclic peptides have an N-terminal (amine group) and C-terminal (ca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ALDH1A1
Aldehyde dehydrogenase 1 family, member A1, also known as ALDH1A1 or retinaldehyde dehydrogenase 1 (RALDH1), is an enzyme that is encoded by the ''ALDH1A1'' gene. Function This protein belongs to the aldehyde dehydrogenases family of proteins and is a member of the ALDH1 subfamily (including ALDH1A2, ALDH1A3, ALDH1B1, ALDH2). Aldehyde dehydrogenase isozymes are NAD(P)-dependent dehydrogenases that catalyze the oxidation of an aldehyde into the corresponding carboxylic acid while reducing NAD+ or NADP+. ALDH1A1 is the only ALDH1 isozyme known to oxidize 9-cis retinaldehyde into 9-cis retinoic acid and thus serve as the only known activator of the Retinoid X receptor alpha, rexinoid nuclear receptor pathway. ALDH1A1 has also been described with activity against other substrates in living systems, including All-Trans-Retinaldehyde, all-trans retinaldehyde as well as oxazaphosphorine, a cyclophosphamide metabolite. Unique among the ALDH1 isozymes, ALDH1A1 is known to possess estera ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
