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Glyoxylate Reductase
Glyoxylate reductase (), first isolated from spinach leaves, is an enzyme that catalyzes the reduction of glyoxylate to glycolate, using the cofactor NADH or NADPH. The systematic name of this enzyme class is glycolate:NAD+ oxidoreductase. Other names in common use include NADH-glyoxylate reductase, glyoxylic acid reductase, and NADH-dependent glyoxylate reductase. Structure The crystal structure of the glyoxylate reductase enzyme from the hyperthermophilic archeon Pyrococcus horiskoshii OT3 has been reported. The enzyme exists in the dimeric form. Each monomer has two domains: a substrate-binding domain where glyoxylate binds, and a nucleotide-binding domain where the NAD(P)H cofactor binds. Mechanism The enzyme catalyzes the transfer of a hydride from NAD(P)H to glyoxylate, causing a reduction of the substrate to glycolate and an oxidation of the cofactor to NAD(P)+. Figure 2 shows the mechanism for this reaction. It is thought that the two residues Glu270 and Hi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spinach
Spinach (''Spinacia oleracea'') is a leafy green flowering plant native to central and western Asia. It is of the order Caryophyllales, family Amaranthaceae, subfamily Chenopodioideae. Its leaves are a common edible vegetable consumed either fresh, or after storage using preservation techniques by canning, freezing, or dehydration. It may be eaten cooked or raw, and the taste differs considerably; the high oxalate content may be reduced by steaming. It is an annual plant (rarely biennial), growing as tall as . Spinach may overwinter in temperate regions. The leaves are alternate, simple, ovate to triangular, and very variable in size: long and broad, with larger leaves at the base of the plant and small leaves higher on the flowering stem. The flowers are inconspicuous, yellow-green, in diameter, and mature into a small, hard, dry, lumpy fruit cluster across containing several seeds. In 2018, world production of spinach was 26.3 million tonnes, with China alone accounti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peroxisome
A peroxisome () is a membrane-bound organelle, a type of microbody, found in the cytoplasm of virtually all eukaryotic cells. Peroxisomes are oxidative organelles. Frequently, molecular oxygen serves as a co-substrate, from which hydrogen peroxide (H2O2) is then formed. Peroxisomes owe their name to hydrogen peroxide generating and scavenging activities. They perform key roles in lipid metabolism and the conversion of reactive oxygen species. Peroxisomes are involved in the catabolism of very long chain fatty acids, branched chain fatty acids, bile acid intermediates (in the liver), D-amino acids, and polyamines, the reduction of reactive oxygen species – specifically hydrogen peroxide – and the biosynthesis of plasmalogens, i.e., ether phospholipids critical for the normal function of mammalian brains and lungs. They also contain approximately 10% of the total activity of two enzymes (Glucose-6-phosphate dehydrogenase and 6-Phosphogluconate dehydrogenase) in the pentose ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kidney Stone
Kidney stone disease, also known as nephrolithiasis or urolithiasis, is a crystallopathy where a solid piece of material (kidney stone) develops in the urinary tract. Kidney stones typically form in the kidney and leave the body in the urine stream. A small stone may pass without causing symptoms. If a stone grows to more than , it can cause blockage of the ureter, resulting in sharp and severe pain in the lower back or abdomen. A stone may also result in blood in the urine, vomiting, or painful urination. About half of people who have had a kidney stone will have another within ten years. Most stones form by a combination of genetics and environmental factors. Risk factors include high urine calcium levels, obesity, certain foods, some medications, calcium supplements, hyperparathyroidism, gout and not drinking enough fluids. Stones form in the kidney when minerals in urine are at high concentration. The diagnosis is usually based on symptoms, urine testing, and medical i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Primary Hyperoxaluria
Primary hyperoxaluria is a rare condition (autosomal recessive), resulting in increased excretion of oxalate (up to 600 mg a day from normal 50 mg a day), with oxalate stones being common. Signs and symptoms Primary hyperoxaluria is an autosomal recessive disease, meaning both copies of the gene contain the mutation. Both parents must have one copy of this mutated gene to pass it on to their child, but they do not typically show signs or symptoms of the disease. A single kidney stone in children or recurrent stones in adults is often the first warning sign of primary hyperoxaluria. Other symptoms range from recurrent urinary tract infections, severe abdominal pain or pain in the side, blood in the urine, to chronic kidney disease and kidney failure. The age of symptom onset, progression and severity can vary greatly from one person to another, even among members of the same family. Some individuals may have mild cases that go undiagnosed well into adulthood; others may ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Recessive
In genetics, dominance is the phenomenon of one variant (allele) of a gene on a chromosome masking or overriding the effect of a different variant of the same gene on the other copy of the chromosome. The first variant is termed dominant and the second recessive. This state of having two different variants of the same gene on each chromosome is originally caused by a mutation in one of the genes, either new (''de novo'') or inherited. The terms autosomal dominant or autosomal recessive are used to describe gene variants on non-sex chromosomes ( autosomes) and their associated traits, while those on sex chromosomes (allosomes) are termed X-linked dominant, X-linked recessive or Y-linked; these have an inheritance and presentation pattern that depends on the sex of both the parent and the child (see Sex linkage). Since there is only one copy of the Y chromosome, Y-linked traits cannot be dominant or recessive. Additionally, there are other forms of dominance such as incomplete d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Genetic Disorder
A genetic disorder is a health problem caused by one or more abnormalities in the genome. It can be caused by a mutation in a single gene (monogenic) or multiple genes (polygenic) or by a chromosomal abnormality. Although polygenic disorders are the most common, the term is mostly used when discussing disorders with a single genetic cause, either in a gene or chromosome. The mutation responsible can occur spontaneously before embryonic development (a ''de novo'' mutation), or it can be Heredity, inherited from two parents who are carriers of a faulty gene (autosomal recessive inheritance) or from a parent with the disorder (autosomal dominant inheritance). When the genetic disorder is inherited from one or both parents, it is also classified as a hereditary disease. Some disorders are caused by a mutation on the X chromosome and have X-linked inheritance. Very few disorders are inherited on the Y linkage, Y chromosome or Mitochondrial disease#Causes, mitochondrial DNA (due to t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nucleic Acid Sequence
A nucleic acid sequence is a succession of Nucleobase, bases signified by a series of a set of five different letters that indicate the order of nucleotides forming alleles within a DNA (using GACT) or RNA (GACU) molecule. By convention, sequences are usually presented from the Directionality (molecular biology), 5' end to the 3' end. For DNA, the Sense (molecular biology), sense strand is used. Because nucleic acids are normally linear (unbranched) polymers, specifying the sequence is equivalent to defining the covalent structure of the entire molecule. For this reason, the nucleic acid sequence is also termed the Biomolecular structure#Primary structure, primary structure. The sequence has capacity to represent information. Biological deoxyribonucleic acid represents the information which directs the functions of an organism. Nucleic acids also have a Nucleic acid secondary structure, secondary structure and Nucleic acid tertiary structure, tertiary structure. Primary structur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
GRHPR
Glyoxylate reductase/hydroxypyruvate reductase is an enzyme that in humans is encoded by the ''GRHPR'' gene. This gene encodes an enzyme with hydroxypyruvate reductase, glyoxylate reductase, and D- glycerate dehydrogenase enzymatic activities. The enzyme has widespread tissue expression and has a role in metabolism. Type II hyperoxaluria Hyperoxaluria is an excessive urinary excretion of oxalate. Individuals with hyperoxaluria often have calcium oxalate kidney stones. It is sometimes called Bird's disease, after Golding Bird, who first described the condition. Causes Hyperoxalur ... is caused by mutations in this gene. GRHPR mutation analysis needs to pay attention to primer design, because allele dropout can cause false-positive result. References External links GeneReviews/NCBI/NIH/UW entry on Primary Hyperoxaluria Type 2 Further reading * * * * * * * * * * * * {{gene-9-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acetohydroxamic Acid
Acetohydroxamic acid (also known as AHA or by the trade name Lithostat) is a drug that is a potent and irreversible enzyme inhibitor of the urease enzyme in various bacteria and plants; it is usually used for urinary tract infections. The molecule is similar to urea but is not hydrolyzable by urease; it thus disrupts the bacteria's metabolism through competitive inhibition. Orphan drug In 1983 the US Food and Drug Administration approved acetohydroxamic acid (AHA) as an orphan drug for "prevention of so-called struvite stones" under the newly enacted Orphan Drug Act of 1983 The Orphan Drug Act of 1983 is a law passed in the United States to facilitate development of orphan drugs—drugs for rare diseases such as Huntington's disease, myoclonus, ALS, Tourette syndrome and muscular dystrophy which affect small numbers .... AHA cannot be patented because it is a standard chemical compound. See also * Salicylhydroxamic acid References {{Urologicals Orphan drugs Hydro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electron Transport Chain
An electron transport chain (ETC) is a series of protein complexes and other molecules that transfer electrons from electron donors to electron acceptors via redox reactions (both reduction and oxidation occurring simultaneously) and couples this electron transfer with the transfer of protons (H+ ions) across a membrane. The electrons that transferred from NADH and FADH2 to the ETC involves 4 multi-subunit large enzymes complexes and 2 mobile electron carriers. Many of the enzymes in the electron transport chain are membrane-bound. The flow of electrons through the electron transport chain is an exergonic process. The energy from the redox reactions creates an electrochemical proton gradient that drives the synthesis of adenosine triphosphate (ATP). In aerobic respiration, the flow of electrons terminates with molecular oxygen as the final electron acceptor. In anaerobic respiration, other electron acceptors are used, such as sulfate. In an electron transport chain, the redo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chloroplast
A chloroplast () is a type of membrane-bound organelle known as a plastid that conducts photosynthesis mostly in plant and algal cells. The photosynthetic pigment chlorophyll captures the energy from sunlight, converts it, and stores it in the energy-storage molecules ATP and NADPH while freeing oxygen from water in the cells. The ATP and NADPH is then used to make organic molecules from carbon dioxide in a process known as the Calvin cycle. Chloroplasts carry out a number of other functions, including fatty acid synthesis, amino acid synthesis, and the immune response in plants. The number of chloroplasts per cell varies from one, in unicellular algae, up to 100 in plants like ''Arabidopsis'' and wheat. A chloroplast is characterized by its two membranes and a high concentration of chlorophyll. Other plastid types, such as the leucoplast and the chromoplast, contain little chlorophyll and do not carry out photosynthesis. Chloroplasts are highly dynamic—they circulat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biosynthesis
Biosynthesis is a multi-step, enzyme-catalyzed process where substrates are converted into more complex products in living organisms. In biosynthesis, simple compounds are modified, converted into other compounds, or joined to form macromolecules. This process often consists of metabolic pathways. Some of these biosynthetic pathways are located within a single cellular organelle, while others involve enzymes that are located within multiple cellular organelles. Examples of these biosynthetic pathways include the production of lipid membrane components and nucleotides. Biosynthesis is usually synonymous with anabolism. The prerequisite elements for biosynthesis include: precursor compounds, chemical energy (e.g. ATP), and catalytic enzymes which may require coenzymes (e.g.NADH, NADPH). These elements create monomers, the building blocks for macromolecules. Some important biological macromolecules include: proteins, which are composed of amino acid monomers joined via peptide bon ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
