An enzyme of the transferase class that catalyzes the conversion of sedoheptulose 7-phosphate and D-glyceraldehyde 3-phosphate to D-ribose 5-phosphate and D-xylulose 5-phosphate in the PENTOSE PHOSPHATE PATHWAY. (Dorland, 27th ed) EC 2.2.1.1.
The coenzyme form of Vitamin B1 present in many animal tissues. It is a required intermediate in the PYRUVATE DEHYDROGENASE COMPLEX and the KETOGLUTARATE DEHYDROGENASE COMPLEX.
A nutritional condition produced by a deficiency of THIAMINE in the diet, characterized by anorexia, irritability, and weight loss. Later, patients experience weakness, peripheral neuropathy, headache, and tachycardia. In addition to being caused by a poor diet, thiamine deficiency in the United States most commonly occurs as a result of alcoholism, since ethanol interferes with thiamine absorption. In countries relying on polished rice as a dietary staple, BERIBERI prevalence is very high. (From Cecil Textbook of Medicine, 19th ed, p1171)
An enzyme of the transferase class that catalyzes the reaction sedoheptulose 7-phosphate and D-glyceraldehyde 3-phosphate to yield D-erythrose 4-phosphate and D-fructose phosphate in the PENTOSE PHOSPHATE PATHWAY. (Dorland, 27th ed) EC 2.2.1.2.
3-((4-Amino-2-methyl-5-pyrimidinyl)methyl)-5-(2- hydroxyethyl)-4-methylthiazolium chloride.
Thiamine antagonist, antimetabolite.
A class of carbohydrates that contains five carbon atoms.
Pentosephosphates are monosaccharides, specifically pentoses, that have a phosphate group attached, playing crucial roles in carbohydrate metabolism, such as being intermediates in the pentose phosphate pathway and serving as precursors for nucleotide synthesis.
An oxidative decarboxylation process that converts GLUCOSE-6-PHOSPHATE to D-ribose-5-phosphate via 6-phosphogluconate. The pentose product is used in the biosynthesis of NUCLEIC ACIDS. The generated energy is stored in the form of NADPH. This pathway is prominent in tissues which are active in the synthesis of FATTY ACIDS and STEROIDS.
A mental disorder associated with chronic ethanol abuse (ALCOHOLISM) and nutritional deficiencies characterized by short term memory loss, confabulations, and disturbances of attention. (Adams et al., Principles of Neurology, 6th ed, p1139)
Enzymes that catalyze the transfer of aldehyde or ketone residues. EC 2.2.
Ribose substituted in the 1-, 3-, or 5-position by a phosphoric acid moiety.
A pentose active in biological systems usually in its D-form.
Thiamine dihydrogen phosphate ester. The monophosphate ester of thiamine. Synonyms: monophosphothiamine; vitamin B1 monophosphate.
The processes by which organisms use simple inorganic substances such as gaseous or dissolved carbon dioxide and inorganic nitrogen as nutrient sources. Contrasts with heterotrophic processes which make use of organic materials as the nutrient supply source. Autotrophs can be either chemoautotrophs (or chemolithotrophs), largely ARCHAEA and BACTERIA, which also use simple inorganic substances for their metabolic energy reguirements; or photoautotrophs (or photolithotrophs), such as PLANTS and CYANOBACTERIA, which derive their energy from light. Depending on environmental conditions some organisms can switch between different nutritional modes (autotrophy; HETEROTROPHY; chemotrophy; or PHOTOTROPHY) to utilize different sources to meet their nutrient and energy requirements.
An acute neurological disorder characterized by the triad of ophthalmoplegia, ataxia, and disturbances of mental activity or consciousness. Eye movement abnormalities include nystagmus, external rectus palsies, and reduced conjugate gaze. THIAMINE DEFICIENCY and chronic ALCOHOLISM are associated conditions. Pathologic features include periventricular petechial hemorrhages and neuropil breakdown in the diencephalon and brainstem. Chronic thiamine deficiency may lead to KORSAKOFF SYNDROME. (Adams et al., Principles of Neurology, 6th ed, pp1139-42; Davis & Robertson, Textbook of Neuropathology, 2nd ed, pp452-3)
Transferases are enzymes transferring a group, for example, the methyl group or a glycosyl group, from one compound (generally regarded as donor) to another compound (generally regarded as acceptor). The classification is based on the scheme "donor:acceptor group transferase". (Enzyme Nomenclature, 1992) EC 2.
An enzyme of the oxidoreductase class that catalyzes the reaction 6-phospho-D-gluconate and NADP+ to yield D-ribulose 5-phosphate, carbon dioxide, and NADPH. The reaction is a step in the pentose phosphate pathway of glucose metabolism. (From Dorland, 27th ed) EC 1.1.1.43.
Softening or loss of brain tissue following CEREBRAL INFARCTION; cerebral ischemia (see BRAIN ISCHEMIA), infection, CRANIOCEREBRAL TRAUMA, or other injury. The term is often used during gross pathologic inspection to describe blurred cortical margins and decreased consistency of brain tissue following infarction. Multicystic encephalomalacia refers to the formation of multiple cystic cavities of various sizes in the cerebral cortex of neonates and infants following injury, most notably perinatal hypoxia-ischemic events. (From Davis et al., Textbook of Neuropathology, 2nd ed, p665; J Neuropathol Exp Neurol, 1995 Mar;54(2):268-75)
A disease caused by a deficiency of thiamine (vitamin B1) and characterized by polyneuritis, cardiac pathology, and edema. The epidemic form is found primarily in areas in which white (polished) rice is the staple food, as in Japan, China, the Philippines, India, and other countries of southeast Asia. (Dorland, 27th ed)
An aldotriose which is an important intermediate in glycolysis and in tryptophan biosynthesis.
3-((4-Amino-2-methyl-5-pyrimidinyl)methyl)-4-methyl-5-(4,6,8,8-tetrahydroxy-3,5,7-trioxa-4,6,8-triphosphaoct-1-yl)thiazolium hydroxide, inner salt, P,P',P''-trioxide. The triphosphate ester of thiamine. In Leigh's disease, this compound is present in decreased amounts in the brain due to a metabolic block in its formation.

Thiamine deficiency is prevalent in a selected group of urban Indonesian elderly people. (1/212)

This cross-sectional study involved 204 elderly individuals (93 males and 111 females). Subjects were randomly recruited using a list on which all 60-75 y-old-people living in seven sub-villages in Jakarta were included. The usual food intake was estimated using semiquantitative food frequency questionnaires. Hemoglobin, plasma retinol, vitamin B-12, red blood cell folate and the percentage stimulation of erythrocyte transketolase (ETK), as an indicator of thiamine status, were analyzed. Median energy intake was below the assessed requirement. More than 75% of the subjects had iron and thiamine intakes of approximately 2/3 of the recommended daily intake, and 20.2% of the study population had folate intake of approximately 2/3 of the recommended daily intake. Intakes of vitamins A and B-12 were adequate. Biochemical assessments demonstrated that 36.6% of the subjects had low thiamine levels (ETK stimulation > 25%). The elderly men tended to have lower thiamine levels than the elderly women. The overall prevalence of anemia was 28.9%, and the elderly women were affected more than the elderly men. Low biochemical status of vitamins A, B-12 and RBC folate was found in 5.4%, 8.8 % and 2.9% of the subjects, respectively. Dietary intakes of thiamine and folate were associated with ETK stimulation and plasma vitamin B-12 concentration (r = 0.176, P = 0.012 and r = 0.77, P = 0.001), respectively. Results of this study suggest that anemia, thiamine and possibly vitamin B-12 deficiency are prevalent in the elderly living in Indonesia. Clearly, micronutrient supplementation may be beneficial for the Indonesian elderly population living in underprivileged areas.  (+info)

Behavior of transaldolase (EC 2.2.1.2) and transketolase (EC 2.2.1.1) Activities in normal, neoplastic, differentiating, and regenerating liver. (2/212)

The objective of this investigation was to throw light on the biological behavior and metabolic regulation of hepatic enzymes of the nonoxidative branch of the pentose phosphate pathway. The activities of transaldolase (EC 2.2.1.2) and trasketolase (EC 2.2.1.1) Were compared in biological conditions that involve modulation of gene expression such as in starvation, in differentiation, after partial hepatectomy, and in a spectrum of hepatomas of different growth rates. The enzyme activities were determined under optimal kinetic conditions by spectrophotometric methods in the 100,000 X g supernatant fluids prepared from tissue homogenates. The kinetic properties of transaldolase and transketolase were similar in normal liver and in rapidly growing hepatoma 3924A. For transaldolase, apparent Km values of 0.13 mM (normal liver) and 0.17 mM (hepatoma) were observed for erythrose 4-phosphate and of 0.30 to 0.35 mM for fructose 6-phosphate. The pH optima in liver and hepatoma were at approximately 6.9 to 7.2. For the transketolase substrates, ribose 5-phosphate and xylulose 5-phosphate, the apparent Km values were 0.3 and 0.5 mM, respectively, in both liver and hepatoma. A broad pH optimum around 7.6 was observed in both tissues. In organ distribution studies, enzyme activities were measured in liver, intestinal mucosa, thymus, kidney, spleen, brain, adipose tissue, lung, heart, and skeletal muscle. Taking the specific activity of liver as 100%, transaldolase activity was the highest in intestinal mucosa (316%) and in thymus (219%); it was the lowest in heart (53%) and in skeletal muscle (21%). Transketolase activity was highest in kidney (155%) and lowest in heart (26%) and skeletal muscle (23%). Starvation decreased transaldolase and transketolase activities in 6 days to 69 and 74%, respectively, of those of the liver of the normal, fed rat. This was in the same range as the decrease in the protein concentration (66%y. In the liver tumors, transaldolase activity was increased 1.5- to 3.4-fold over the activities observed in normal control rat liver. Transketolase activity showed no relationship to tumor proliferation rate. In the regenerating liver at 24 hr after partial hepatectomy, the activity of both pentose phosphate pathway enzymes was in the same range as that of the sham-operated controls. In differentiation at the postnatal age of 5, 12, 23, and 32 days, hepatic transaldolase activities were 33, 44, 55, and 72%, respectively, of the activities observed in the 60-day-old, adult male rat. During the same period, transketolase activ-ties were 18, 21, 26, and 55% of the activities observed in liver of adult rat. The demonstration of increased transaldolase activity in hepatomas, irrespective of the degree of tumor malignancy, differentiation, or growth rate, suggests that the reprogramming of gene expression in malignant transformation is linked with an increase in the expression of this pentose phosphate pathway enzyme...  (+info)

Hyperproduction of tryptophan by Corynebacterium glutamicum with the modified pentose phosphate pathway. (3/212)

A classically derived tryptophan-producing Corynebacterium glutamicum strain was recently significantly improved both by plasmid-mediated amplification of the genes for the rate-limiting enzymes in the terminal pathways and by construction of a plasmid stabilization system so that it produced more tryptophan. This engineered strain, KY9218 carrying pKW9901, produced 50 g of tryptophan per liter from sucrose after 80 h in fed-batch cultivation without antibiotic pressure. Analysis of carbon balances showed that at the late stage of the fermentation, tryptophan yield decreased with a concomitant increase in CO2 yield, suggesting a transition in the distribution of carbon flow from aromatic biosynthesis toward the tricarboxylic acid cycle via glycolysis. To circumvent this transition by increasing the supply of erythrose 4-phosphate, a direct precursor of aromatic biosynthesis, the transketolase gene of C. glutamicum was coamplified in the engineered strain by using low- and high-copy-number plasmids which were compatible with the resident plasmid pKW9901. The presence of the gene in low copy numbers contributed to improvement of tryptophan yield, especially at the late stage, and led to accumulation of more tryptophan (57 g/liter) than did its absence, while high-copy-number amplification of the gene resulted in a tryptophan production level even lower than that resulting from the absence of the gene due to reduced growth and sugar consumption. In order to assemble all the cloned genes onto a low-copy-number plasmid, the high-copy-number origin of pKW9901 was replaced with the low-copy-number one, generating low-copy-number plasmid pSW9911, and the transketolase gene was inserted to yield pIK9960. The pSW9911-carrying producer showed almost the same fermentation profiles as the pKW9901 carrier in fed-batch cultivation without antibiotic pressure. Under the same culture conditions, however, the pIK9960 carrier achieved a final tryptophan titer of 58 g/liter, which represented a 15% enhancement over the titers achieved by the pKW9901 and pSW9911 carriers.  (+info)

Vitamin B status in patients with chronic fatigue syndrome. (4/212)

Some patients with chronic fatigue syndrome say they benefit from taking vitamin supplements. We assessed functional status for the B vitamins pyridoxine, riboflavin and thiamine in 12 vitamin-untreated CFS patients and in 18 healthy controls matched for age and sex. Vitamin-dependent activities--aspartate aminotransferase (AST) for pyridoxine, glutathione reductase (GTR) for riboflavin, transketolase (TK) for thiamine--were measured in erythrocyte haemolysates before and after in-vitro addition of the relevant vitamin. For all three enzymes basal activity (U/g Hb) was lower in CFS patients than in controls: AST 2.84 (SD 0.62) vs 4.61 (1.43), P < 0.001; GTR 6.13 (1.89) vs 7.42 (1.25), P < 0.04; TK 0.50 (0.13) vs 0.60 (0.07), P < 0.04. This was also true of activated values: AST 4.91 (0.54) vs 7.89 (2.11), P < 0.001; GTR 8.29 (1.60) vs 10.0 (1.80), P < 0.001; TK 0.56 (0.19) vs 0.66 (0.08), P < 0.07. The activation ratios, however, did not differ between the groups. These data provide preliminary evidence of reduced functional B vitamin status, particularly of pyridoxine, in CFS patients.  (+info)

Oxythiamine and dehydroepiandrosterone induce a G1 phase cycle arrest in Ehrlich's tumor cells through inhibition of the pentose cycle. (5/212)

Transketolase (TK) reactions play a crucial role in tumor cell nucleic acid ribose synthesis utilizing glucose carbons, yet, current cancer treatments do not target this central pathway. Experimentally, a dramatic decrease in tumor cell proliferation after the administration of the TK inhibitor oxythiamine (OT) was observed in several in vitro and in vivo tumor models. Here, we demonstrate that pentose cycle (PC) inhibitors, OT and dehydroepiandrosterone (DHEA), efficiently regulate the cell cycle and tumor proliferation processes. Increasing doses of OT or DHEA were administered by daily intraperitoneal injections to Ehrlich's ascites tumor hosting mice for 4 days. The tumor cell number and their cycle phase distribution profile were determined by DNA flow histograms. Tumors showed a dose dependent increase in their G0-G1 cell populations after both OT and DHEA treatment and a simultaneous decrease in cells advancing to the S and G2-M cell cycle phases. This effect of PC inhibitors was significant, OT was more effective than DHEA, both drugs acted synergistically in combination and no signs of direct cell or host toxicity were observed. Direct inhibition of PC reactions causes a G1 cell cycle arrest similar to that of 2-deoxyglucose treatment. However, no interference with cell energy production and cell toxicity is observed. PC inhibitors, specifically ones targeting TK, introduce a new target site for the development of future cancer therapies to inhibit glucose utilizing pathways selectively for nucleic acid production.  (+info)

Biochemical evidence of thiamin deficiency in young Ghanian children. (6/212)

Detailed biochemical studies for nutritional status were carried out on 146 Ghanaian children ages 6 months to 6 years over a 2-year period. Study children comprised three main groups: severe protein-calorie malnutrition; mild to moderate protein-calorie malnutrition and apparently healthy children. Erythrocyte transketolase activity and the percentage of erythrocyte transketolase pyrophosphate effect were also determined. In the first year of the study elevated percentage of transketolase pyrophosphate effect indicative of thiamin deficiency was found in all three of the above-mentioned groups, with the most widespread deficiency in the normal groups. In year 2, repeat studies of the severely malnourished group after 2 weeks of nutritional therapy with the administration of vitamin capsules, which included thiamin, resulted in the normalization of transketolase pyrophosphate effect. Apoenzyme activity was comparable in all groups studied. There were no obvious clinical signs of thiamin deficiency, although sensory testing was not performed. A relatively large number of children with high percentage of transketolase pyrosphosphate effect also had serum folic acid deficiency. This evidence of widespread biochemical thiamin deficiency is indicative of an at-risk population among young children for clinical thiamin deficiency. Further studies are needed to identify whether the problem is inadequate thiamin intake, destruction of thiamin by thiaminases or food preparation methods, or malabsorption of thiamin.  (+info)

Thiamin and pyridoxine requirements during intravenous hyperalimentation. (7/212)

Studies were undertaken to determine rational dosages of vitamin B1 and B6 during long-term intravenous hyperalimentation, using more sensitive techniques than formerly used to evaluate B1 and B6 status. A standard vitamin combination, type A, (usually commercially available products) has been used up to now because of convenience, disregarding the effects of long-term administration. This combination lacks biotin, folic acid, and vitamin E and contains from 10 to 100 times the dietary allowances of such vitamins as B1, B2, B6, B12, and C. In response to the possibility of vitamin overdose, two new vitamin combinations, type B (from commercial products) and type C (a convenient and easily administered combination produced at the hospital) were developed in order to provide the normal dietary allowances and at the same time eliminate any harmful side-effects. From the results obtained, 5 mg/day for thiamin HCl and 3 mg/day for pyridoxine HCl in type B and type C were found to be a sufficient and safe level as opposed to 55 mg/day for thiamin HCl and 102 mg/day for pyridoxine HCl in type A.  (+info)

Molecular analysis of the Corynebacterium glutamicum transketolase gene. (8/212)

Transketolase is important in production of the aromatic amino acids in Corynebacterium glutamicum. The complete nucleotide sequence of the C. glutamicum transketolase gene has been identified. The DNA-derived protein sequence is highly similar to the transketolase of Mycobacterium tuberculosis, taxonomically related to C. glutamicum. The alignment of the N-terminus regions between both transketolases showed TTG to be the most probable start codon. Potential ribosomal binding and promoter regions were situated upstream from the TTG. The deduced amino acid sequence consists of 700 residues with a calculated molecular mass of 75 kDa, and contains all amino acid residues involved in cofactor and substrate binding in the well-characterized yeast transketolase sequence.  (+info)

Transketolase is an enzyme found in most organisms, from bacteria to humans. It plays a crucial role in the pentose phosphate pathway (PPP), which is a metabolic pathway that runs alongside glycolysis in the cell cytoplasm. The PPP provides an alternative way of generating energy and also serves to provide building blocks for new cellular components, particularly nucleotides.

Transketolase functions by catalyzing the transfer of a two-carbon ketol group from a ketose (a sugar containing a ketone functional group) to an aldose (a sugar containing an aldehyde functional group). This reaction forms a new ketose and an aldose, effectively converting three-carbon sugars into five-carbon sugars, or vice versa.

In humans, transketolase is essential for the production of NADPH, an important reducing agent in the cell, and for the synthesis of certain amino acids and nucleotides. Deficiencies in this enzyme can lead to metabolic disorders such as pentosuria.

Thiamine pyrophosphate (TPP) is the active form of thiamine (vitamin B1) that plays a crucial role as a cofactor in various enzymatic reactions, particularly in carbohydrate metabolism. TPP is essential for the functioning of three key enzymes: pyruvate dehydrogenase, alpha-ketoglutarate dehydrogenase, and transketolase. These enzymes are involved in critical processes such as the conversion of pyruvate to acetyl-CoA, the oxidative decarboxylation of alpha-ketoglutarate in the Krebs cycle, and the pentose phosphate pathway, which is important for generating reducing equivalents (NADPH) and ribose sugars for nucleotide synthesis. A deficiency in thiamine or TPP can lead to severe neurological disorders, including beriberi and Wernicke-Korsakoff syndrome, which are often observed in alcoholics due to poor nutrition and impaired thiamine absorption.

Thiamine deficiency, also known as beriberi, is a condition that results from inadequate intake or impaired absorption of thiamine (vitamin B1), which is essential for energy metabolism and nerve function. This deficiency can lead to various symptoms such as peripheral neuropathy, muscle weakness, heart failure, and in severe cases, Wernicke-Korsakoff syndrome, a neurological disorder associated with alcoholism. Thiamine deficiency is commonly found in populations with poor nutrition, alcohol dependence, and gastrointestinal disorders affecting nutrient absorption.

Transaldolase is not a medical term per se, but it is a term used in biochemistry and molecular biology. Transaldolase is an enzyme involved in the pentose phosphate pathway (PPP), which is a metabolic pathway that supplies reducing energy to cells by converting glucose-6-phosphate into ribulose-5-phosphate, a key intermediate in the synthesis of nucleotides.

The medical relevance of transaldolase lies in its role in maintaining cellular redox balance and providing precursors for nucleic acid synthesis. Defects in the PPP can lead to various metabolic disorders, including some forms of congenital cataracts, neurological dysfunction, and growth retardation. However, specific diseases or conditions directly attributed to transaldolase deficiency are not well-established.

Thiamine, also known as vitamin B1, is a water-soluble vitamin that plays a crucial role in certain metabolic reactions, particularly in the conversion of carbohydrates into energy in the body. It is essential for the proper functioning of the heart, nerves, and digestive system. Thiamine acts as a cofactor for enzymes involved in the synthesis of neurotransmitters and the metabolism of carbohydrates, lipids, and proteins. Deficiency in thiamine can lead to serious health complications, such as beriberi (a disease characterized by peripheral neuropathy, muscle wasting, and heart failure) and Wernicke-Korsakoff syndrome (a neurological disorder often seen in alcoholics due to chronic thiamine deficiency). Thiamine is found in various foods, including whole grains, legumes, pork, beef, and fortified foods.

Oxythiamine is not a medication or a condition, but rather a chemical compound. It is an oxidized form of thiamine (vitamin B1), which means it has been changed by the addition of oxygen molecules. Oxythiamine is used in research to study the effects of thiamine deficiency and to investigate the role of thiamine in various biological processes. It is not used as a medication in humans or animals.

A pentose is a monosaccharide (simple sugar) that contains five carbon atoms. The name "pentose" comes from the Greek word "pente," meaning five, and "ose," meaning sugar. Pentoses play important roles in various biological processes, such as serving as building blocks for nucleic acids (DNA and RNA) and other biomolecules.

Some common pentoses include:

1. D-Ribose - A naturally occurring pentose found in ribonucleic acid (RNA), certain coenzymes, and energy-carrying molecules like adenosine triphosphate (ATP).
2. D-Deoxyribose - A pentose that lacks a hydroxyl (-OH) group on the 2' carbon atom, making it a key component of deoxyribonucleic acid (DNA).
3. Xylose - A naturally occurring pentose found in various plants and woody materials; it is used as a sweetener and food additive.
4. Arabinose - Another plant-derived pentose, arabinose can be found in various fruits, vegetables, and grains. It has potential applications in the production of biofuels and other bioproducts.
5. Lyxose - A less common pentose that can be found in some polysaccharides and glycoproteins.

Pentoses are typically less sweet than hexoses (six-carbon sugars) like glucose or fructose, but they still contribute to the overall sweetness of many foods and beverages.

Pentose phosphates are monosaccharides that contain five carbon atoms and one phosphate group. They play a crucial role in various metabolic pathways, including the pentose phosphate pathway (PPP), which is a major source of NADPH and ribose-5-phosphate for the synthesis of nucleotides.

The pentose phosphate pathway involves two main phases: the oxidative phase and the non-oxidative phase. In the oxidative phase, glucose-6-phosphate is converted to ribulose-5-phosphate, producing NADPH and CO2 as byproducts. Ribulose-5-phosphate can then be further metabolized in the non-oxidative phase to produce other pentose phosphates or converted back to glucose-6-phosphate through a series of reactions.

Pentose phosphates are also important intermediates in the synthesis of nucleotides, coenzymes, and other metabolites. Abnormalities in pentose phosphate pathway enzymes can lead to various metabolic disorders, such as defects in erythrocyte function and increased susceptibility to oxidative stress.

The Pentose Phosphate Pathway (also known as the Hexose Monophosphate Shunt or HMP Shunt) is a metabolic pathway that runs parallel to glycolysis. It serves two major functions:

1. Providing reducing equivalents in the form of NADPH for reductive biosynthesis and detoxification processes.
2. Generating ribose-5-phosphate, a pentose sugar used in the synthesis of nucleotides and nucleic acids (DNA and RNA).

This pathway begins with the oxidation of glucose-6-phosphate to form 6-phosphogluconolactone, catalyzed by the enzyme glucose-6-phosphate dehydrogenase. The resulting NADPH is used in various anabolic reactions and antioxidant defense systems.

The Pentose Phosphate Pathway also includes a series of reactions called the non-oxidative branch, which interconverts various sugars to meet cellular needs for different types of monosaccharides. These conversions are facilitated by several enzymes including transketolase and transaldolase.

Alcohol Amnestic Disorder is not listed as a separate disorder in the current edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5), which is used by mental health professionals to diagnose mental conditions. However, it was previously included in earlier editions as a subtype of Amnestic Disorder due to the effects of substance use or exposure to toxins.

Alcohol Amnestic Disorder is characterized by significant memory impairment that is directly caused by alcohol consumption. This disorder can result in anterograde amnesia, which is the inability to form new memories after drinking, and/or retrograde amnesia, which involves forgetting previously learned information or personal experiences.

The diagnosis of Alcohol Amnestic Disorder typically requires a comprehensive medical and neuropsychological evaluation to determine the extent and nature of memory impairment, as well as to rule out other potential causes for cognitive decline. Treatment usually involves a combination of abstinence from alcohol, pharmacotherapy, and psychosocial interventions to address substance use disorder and any co-occurring mental health conditions.

Aldehyde-ketone transferases are a group of enzymes that catalyze the transfer of an aldehyde or ketone group from one molecule to another. These enzymes play a crucial role in various metabolic pathways, including the detoxification of harmful aldehydes produced during alcohol metabolism and the biosynthesis of complex carbohydrates and lipids.

One example of an aldehyde-ketone transferase is acetaldehyde dehydrogenase (ALDH), which is responsible for converting toxic acetaldehyde, a byproduct of alcohol metabolism, into non-toxic acetate. Another example is mevalonate kinase, which transfers a phosphate group to mevalonic acid, an important intermediate in the biosynthesis of cholesterol and other steroids.

Deficiencies or mutations in aldehyde-ketone transferases can lead to various metabolic disorders and diseases, such as alcohol intolerance, nonalcoholic fatty liver disease, and certain inherited neurological conditions.

Ribose monophosphates are organic compounds that play a crucial role in the metabolism of cells, particularly in energy transfer and nucleic acid synthesis. A ribose monophosphate is formed by the attachment of a phosphate group to a ribose molecule, which is a type of sugar known as a pentose.

In biochemistry, there are two important ribose monophosphates:

1. Alpha-D-Ribose 5-Phosphate (ADP-Ribose): This compound serves as an essential substrate in various cellular processes, including DNA repair, chromatin remodeling, and protein modification. The enzyme that catalyzes the formation of ADP-ribose is known as poly(ADP-ribose) polymerase (PARP).
2. Ribulose 5-Phosphate: This compound is a key intermediate in the Calvin cycle, which is the process by which plants and some bacteria convert carbon dioxide into glucose during photosynthesis. Ribulose 5-phosphate is formed from ribose 5-phosphate through a series of enzymatic reactions.

Ribose monophosphates are essential for the proper functioning of cells and have implications in various physiological processes, as well as in certain disease states.

Ribose is a simple carbohydrate, specifically a monosaccharide, which means it is a single sugar unit. It is a type of sugar known as a pentose, containing five carbon atoms. Ribose is a vital component of ribonucleic acid (RNA), one of the essential molecules in all living cells, involved in the process of transcribing and translating genetic information from DNA to proteins. The term "ribose" can also refer to any sugar alcohol derived from it, such as D-ribose or Ribitol.

Thiamine monophosphate (TMP) is a biochemical compound that is a derivative of thiamine (vitamin B1). It is a cofactor for several enzymes involved in key metabolic processes, particularly in the conversion of carbohydrates into energy. TMP plays an essential role in the metabolism of carbohydrates, amino acids, and neurotransmitters.

Thiamine monophosphate is formed when thiamine undergoes phosphorylation by the enzyme thiamine pyrophosphokinase. This reaction adds a phosphate group to the thiamine molecule, resulting in the formation of TMP. Thiamine monophosphate can then be further phosphorylated to form thiamine triphosphate (TTP) or dephosphorylated back to thiamine.

Deficiency in thiamine and its derivatives, including TMP, can lead to several medical conditions, such as beriberi, Wernicke-Korsakoff syndrome, and other neurological disorders. These conditions are often associated with impaired energy metabolism, nerve damage, and cognitive decline. Proper intake of thiamine through diet or supplementation is crucial for maintaining normal physiological functions and preventing these health issues.

Autotrophic processes refer to the ability of certain organisms, known as autotrophs, to synthesize their own organic nutrients from inorganic substances using light or chemical energy. This process is essential for the production of organic matter and the formation of the basis of food chains in ecosystems.

In autotrophic processes, organisms use energy to convert carbon dioxide into organic compounds, such as glucose, through a series of metabolic reactions known as carbon fixation. There are two main types of autotrophic processes: photosynthesis and chemosynthesis.

Photosynthesis is the process used by plants, algae, and some bacteria to convert light energy from the sun into chemical energy in the form of organic compounds. This process involves the use of chlorophyll and other pigments to capture light energy, which is then converted into ATP and NADPH through a series of reactions known as the light-dependent reactions. These energy carriers are then used to power the Calvin cycle, where carbon dioxide is fixed into organic compounds.

Chemosynthesis, on the other hand, is the process used by some bacteria to convert chemical energy from inorganic substances, such as hydrogen sulfide or methane, into organic compounds. This process does not require light energy and typically occurs in environments with limited access to sunlight, such as deep-sea vents or soil.

Overall, autotrophic processes are critical for the functioning of ecosystems and the production of food for both plants and animals.

Wernicke Encephalopathy is a neuropsychiatric disorder that is caused by a deficiency of thiamine (vitamin B1). It is characterized by a classic triad of symptoms: confusion, oculomotor dysfunction (such as nystagmus and ophthalmoplegia), and gait ataxia. Other symptoms can include memory loss, apathy, and hypothermia.

Wernicke Encephalopathy is most commonly seen in alcoholics due to poor nutrition, but it can also occur in people with conditions that cause malabsorption or increased thiamine requirements, such as AIDS, cancer, and chronic diarrhea. Immediate treatment with thiamine replacement therapy is necessary to prevent progression of the disease and potential permanent neurological damage. If left untreated, Wernicke Encephalopathy can lead to Korsakoff's syndrome, a chronic memory disorder.

Transferases are a class of enzymes that facilitate the transfer of specific functional groups (like methyl, acetyl, or phosphate groups) from one molecule (the donor) to another (the acceptor). This transfer of a chemical group can alter the physical or chemical properties of the acceptor molecule and is a crucial process in various metabolic pathways. Transferases play essential roles in numerous biological processes, such as biosynthesis, detoxification, and catabolism.

The classification of transferases is based on the type of functional group they transfer:

1. Methyltransferases - transfer a methyl group (-CH3)
2. Acetyltransferases - transfer an acetyl group (-COCH3)
3. Aminotransferases or Transaminases - transfer an amino group (-NH2 or -NHR, where R is a hydrogen atom or a carbon-containing group)
4. Glycosyltransferases - transfer a sugar moiety (a glycosyl group)
5. Phosphotransferases - transfer a phosphate group (-PO3H2)
6. Sulfotransferases - transfer a sulfo group (-SO3H)
7. Acyltransferases - transfer an acyl group (a fatty acid or similar molecule)

These enzymes are identified and named according to the systematic nomenclature of enzymes developed by the Nomenclature Committee of the International Union of Biochemistry and Molecular Biology (IUBMB). The naming convention includes the class of enzyme, the specific group being transferred, and the molecules involved in the transfer reaction. For example, the enzyme that transfers a phosphate group from ATP to glucose is named "glucokinase."

Phosphogluconate dehydrogenase (PGD) is an enzyme that plays a crucial role in the pentose phosphate pathway, which is a metabolic pathway that supplies reducing energy to cells by converting glucose into ribose-5-phosphate and NADPH.

PGD catalyzes the third step of this pathway, in which 6-phosphogluconate is converted into ribulose-5-phosphate, with the concurrent reduction of NADP+ to NADPH. This reaction is essential for the generation of NADPH, which serves as a reducing agent in various cellular processes, including fatty acid synthesis and antioxidant defense.

Deficiencies in PGD can lead to several metabolic disorders, such as congenital nonspherocytic hemolytic anemia, which is characterized by the premature destruction of red blood cells due to a defect in the pentose phosphate pathway.

Encephalomalacia is a medical term that refers to the softening and degeneration of brain tissue. It is typically caused by an injury, infection, or lack of oxygen supply to the brain. This condition can lead to various neurological symptoms depending on the location and extent of the damage in the brain. Encephalomalacia may result in cognitive impairments, motor function loss, speech difficulties, and other long-term disabilities. Treatment options vary based on the underlying cause and severity of the condition but often include rehabilitation therapies to help manage symptoms and improve quality of life.

Beriberi is a medical condition caused by a deficiency in thiamine (vitamin B1). This deficiency can lead to various symptoms, including peripheral neuropathy, muscle wasting, and heart failure. There are two main types of beriberi: wet beriberi, which affects the cardiovascular system, and dry beriberi, which primarily affects the nervous system.

Wet beriberi can cause symptoms such as shortness of breath, rapid heart rate, and fluid accumulation in the legs and lungs. Dry beriberi, on the other hand, is characterized by symptoms such as numbness, tingling, and weakness in the hands and feet, muscle wasting, and difficulty walking.

Beriberi can be prevented through a balanced diet that includes adequate amounts of thiamine-rich foods, such as whole grains, legumes, pork, beef, and fortified cereals. Treatment for beriberi typically involves administering thiamine supplements to restore normal levels of the vitamin in the body. In severe cases, hospitalization may be necessary to provide supportive care and monitor the patient's condition.

Glyceraldehyde 3-phosphate (G3P) is a crucial intermediate in both glycolysis and gluconeogenesis metabolic pathways. It is an triose sugar phosphate, which means it contains three carbon atoms and has a phosphate group attached to it.

In the glycolysis process, G3P is produced during the third step of the process from the molecule dihydroxyacetone phosphate (DHAP) via the enzyme triosephosphate isomerase. In the following steps, G3P is converted into 1,3-bisphosphoglycerate, which eventually leads to the production of ATP and NADH.

In gluconeogenesis, G3P is produced from the reverse reaction of the glycolytic enzyme glyceraldehyde-3-phosphate dehydrogenase, using the molecule dihydroxyacetone phosphate (DHAP) as a starting point. G3P is then converted into glucose-6-phosphate, which can be further metabolized or released from the cell.

It's important to note that Glyceraldehyde 3-Phosphate plays a key role in energy production and carbohydrate metabolism.

Thiamine triphosphate (TTP) is not a widely recognized or used medical term in the context of defining a specific disease, condition, or diagnostic marker. However, thiamine, also known as vitamin B1, is an essential nutrient that plays a crucial role in various bodily functions, including nerve function and energy metabolism.

Thiamine triphosphate (TTP) is a biochemical compound formed from thiamine and adenosine triphosphate (ATP). TTP acts as a cofactor for several enzymes involved in the metabolism of carbohydrates, amino acids, and neurotransmitters. Its exact physiological role and significance are still under investigation, but it is believed to have a role in neuronal excitability, synaptic plasticity, and energy homeostasis.

In summary, Thiamine Triphosphate (TTP) is a biochemical compound that plays a role in various metabolic processes, particularly in the nervous system. However, it does not have a specific medical definition as a disease or condition.

The following human genes encode proteins with transketolase activity: TKT (transketolase) TKTL1 (transketolase-like protein 1 ... Transketolase (abbreviated as TK) is an enzyme that, in humans, is encoded by the TKT gene. It participates in both the pentose ... Transketolase is abundantly expressed in the mammalian cornea by the stromal keratocytes and epithelial cells and is reputed to ... Transketolase activity is decreased in deficiency of thiamine, which in general is due to malnutrition. Several diseases are ...
In enzymology, a formaldehyde transketolase (EC 2.2.1.3) is an enzyme that catalyzes the chemical reaction D-xylulose 5- ... Kato N, Higuchi T, Sakazawa C, Nishizawa T, Tani Y, Yamada H (1982). "Purification and properties of a transketolase ... Waites MJ, Quayle JR (1981). "The interrelation transketolase and dihydroxyacetone synthase activities in the methylotrophic ... A. Trotsenko (1981). "Separation of transketolase and dihydroxyacetone synthase from methylotrophic yeasts" [Separation of ...
Transketolase-like-1 (TKTL1) is a gene closely related to the transketolase gene (TKT). It emerged in mammals during the course ... In addition to the transketolase genes TKT and TKTL1, there is another member of the transketolase gene family in mammals, the ... "TKTL1 transketolase-like 1". Entrez Gene. U.S. National Library of Medicine. Pinson, Anneline; Xing, Lei; Namba, Takashi; ... Up to now, it is or was assumed that transketolases are enzymes that are active as homodimers. The detection of TKTL1-TKT ...
Transketolase-like protein 2 is an enzyme that in humans is encoded by the TKTL2 gene. GRCh38: Ensembl release 89: ... "Entrez Gene: TKTL2 transketolase-like 2". Hartley JL, Temple GF, Brasch MA (2001). "DNA cloning using in vitro site-specific ...
"Nucleotide and predicted amino acid sequence of a cDNA clone encoding part of human transketolase". Biochem. Biophys. Res. ... "Chromosomal location of the human transketolase gene". Cytogenet. Cell Genet. 61 (4): 274-5. doi:10.1159/000133421. PMID ...
Dehydrogenase E1 and transketolase domain containing 1 is a protein that in humans is encoded by the DHTKD1 gene. This gene ... "Entrez Gene: Dehydrogenase E1 and transketolase domain containing 1". Danhauser K, Sauer SW, Haack TB, Wieland T, Staufner C, ...
It is formed by transketolase and acted upon by transaldolase. Sedoheptulokinase is an enzyme that uses sedoheptulose and ATP ...
One as-yet-unreplicated study has associated susceptibility to this syndrome with a hereditary deficiency of transketolase, an ... Nixon, Peter F.; Kaczmarek, M. Jan; Tate, Jill; Kerr, Ray A.; Price, John (1984). "An erythrocyte transketolase isoenzyme ...
This category consists of various transketolases and transaldolases. Transaldolase, the namesake of aldehyde transferases, is ...
F6P has two carbons removed by transketolase, giving erythrose-4-phosphate (E4P). The two carbons on transketolase are added to ... The ketose S7P has two carbons removed by transketolase, giving ribose-5-phosphate (R5P), and the two carbons remaining on ... transketolase are transferred to one of the G3P, giving another Xu5P. This leaves one G3P as the product of fixation of 3 CO 2 ...
To be specific, this enzyme belongs to the transketolase and transaldolase families. Common names for the enzyme are: MenD ...
The sulfoglycolytic transketolase (sulfo-TL) pathway was first identified in Clostridium sp. MSTE9. It involves isomerization ... whereupon a second round of transketolase catalyzed reaction cleaves SE to sulfoacetaldehyde, while the non-sulfonated C2- ... of SQ to sulfofructose, and then a transketolase cleaves SF to 4-sulfoerythrose (SE), while the non-sulfonated C2-moiety is ...
The final non-oxidative step of the pathway is a transketolase reaction. A transketolase utilizes a thiamine pyrophosphate, or ...
... mainly acts on peripheral tissues through an increase in transketolase activity. Benfotiamine is a lipid ... Administration of benfotiamine may increase intracellular levels of thiamine diphosphate, a cofactor of transketolase. Based on ...
Sawada K, Taki A, Yamakawa T, Seki M (November 2009). "Key role for transketolase activity in erythritol production by ...
In particular, magnesium, a cofactor of transketolase which may induce or aggravate the disease. Other supplements may also be ... Thiamine can be measured using an erythrocyte transketolase activity assay, or by activation by measurement of in vitro ... Selected genetic mutations, including presence of the X-linked transketolase-like 1 gene, SLC19A2 thiamine transporter protein ...
DHA synthase acts as a transferase (transketolase) to transfer part of xylulose 5-phosphate to DHA. Then these 3 molecules of ... WAITES, M. J.; QUAYLE, J. R. (1981). "The Interrelation between Transketolase and Dihydroxyacetone Synthase Activities in the ...
"Primary structure and phylogeny of the Calvin cycle enzymes transketolase and fructosebisphosphate aldolase of Xanthobacter ...
This enzyme converts ribulose 5-phosphate into the appropriate epimer for the transketolase reaction, xylulose 5-phosphate. ...
In the case of transketolase, this attacks a new substrate molecule to form a new carbon-carbon bond.) In what is essentially ... Thiamine pyrophosphate is synthesized in the cytosol and is required in the cytosol for the activity of transketolase and in ... and transketolase, TPP catalyses the reversible decarboxylation reaction (aka cleavage of a substrate compound at a carbon- ... dehydrogenase complex Branched-chain amino acid dehydrogenase complex 2-hydroxyphytanoyl-CoA lyase Transketolase Chemically, ...
Transketolase and transaldolase convert two molecules of F6P and one molecule of G3P to three molecules of R5P. During rapid ...
This enzyme has the Enzyme Commission Code is 2.2.1.6, which means that the enzyme is a transketolase or a transaldolase, which ... In this case, acetolactate synthase is a transketolase, which moves back and forth, having both catabolic and anabolic forms. ...
A positive diagnosis test for thiamine deficiency involves measuring the activity of the enzyme transketolase in erythrocytes ( ... Erythrocyte transketolase activation assay). Alternatively, thiamine and its phosphorylated derivatives can directly be ...
... directly inhibits the enzyme transketolase, leading to a build up of reactive oxygen species (ROS) and stress-induced ...
... and transketolase. A lack of thiamine in the cells may therefore prevent neurons from maintaining necessary adenosine ...
... transaldolases and transketolases, respectively). The systematic name of this enzyme class is 3-hydroxybutan-2-one:D-ribose-5- ... from DL-acetoin and D-ribose 5-phosphate by a transketolase mutant of Bacillus pumilus". Agric. Biol. Chem. 47 (7): 1545-1553. ...
... transaldolases and transketolases, respectively). Other names in common use include 2-hydroxy-3-oxoadipate glyoxylate-lyase ( ...
... transaldolases and transketolases, respectively). The systematic name of this enzyme class is pyruvate:d-glyceraldehyde-3- ...
... transaldolases and transketolases, respectively). The systematic name of this enzyme class is fluoroacetaldehyde:L-threonine ...
... transketolase and phosphoketolase revisited in light of recent structural data". Bioorganic Chemistry. 57: 263-80. doi:10.1016/ ...
The following human genes encode proteins with transketolase activity: TKT (transketolase) TKTL1 (transketolase-like protein 1 ... Transketolase (abbreviated as TK) is an enzyme that, in humans, is encoded by the TKT gene. It participates in both the pentose ... Transketolase is abundantly expressed in the mammalian cornea by the stromal keratocytes and epithelial cells and is reputed to ... Transketolase activity is decreased in deficiency of thiamine, which in general is due to malnutrition. Several diseases are ...
This novel reconstituted transketolase is thermally stable with no loss of activity after incubation for 1 h at 70°C and is ... The X-ray structure of the holo reconstituted α 2 β 2 tetrameric transketolase has been determined to 1.4 Å resolution. In ... A novel transketolase has been reconstituted from two separate polypeptide chains encoded by a split-gene identified in the ... N-terminal component of the split chain transketolase. A [auth AAA],. C [auth CCC]. 309. Carboxydothermus hydrogenoformans. ...
Human transketolase (TKT, EC 2.2.1.1) catalyzes transfers two-carbon units from ketoses (donor) to aldoses (acceptor). Abnormal ... Amyloid-like aggregation of human transketolase. Human transketolase (TKT, EC 2.2.1.1) catalyzes transfers two-carbon units ...
Search Transketolase as keywords on MyScienceWorks publications - page 1 ... Transketolase Serves as a Biomarker for Poor Prognosis in Human Lung Adenocarcinoma. Niu, Cong Qiu, Wenjia Li, Xiangyang Li, ... The influence of transketolase on lipid biosynthesis in the yeast Yarrowia lipolytica Dobrowolski, Adam Mirończuk, Aleksandra M ... Erythrocyte transketolase activity coefficient (ETKAC) assay protocol for the assessment of thiamine status. Jones, Kerry S ...
Transketolase_C; Transketolase, C-terminal domain. * NM_001410183.1 → NP_001397112.1 2-oxoisovalerate dehydrogenase subunit ...
Transketolase. NMCC_2038. fmt. Methionyl-tRNA formyltransferase. *Gene IDs correspond to gene identifiers in the clonal complex ...
Transketolase (Tkt). P99161. 1.67 ↓. 7. 6-phosphogluconate dehydrogenase, decarboxylating (Gnd). P63334. 1.94 ↓. 1.85 ↓. ...
Wij bieden algemene ziekenhuiszorg dichtbij huis. maar ook toegang tot academische en specialistische zorg.. ...
... transketolase; 73, ribulose-phosphate 3-epimerase; 74, phosphoribulokinase; 75, "aerobic" carbon monoxide dehydrogenase (coxLSM ...
Transketolase, found mainly in myelinated neurons, is a thiamine-dependent enzyme of the pentose phosphate pathway; it ... Erythrocyte transketolase activity is lower in nondialyzed patients than in dialyzed patients. Guanidinosuccinic acid can ...
In which metabolic pathway is transketolase involved?. *Which essential organic cofactor/prosthetic group is essential for the ...
Synthesis of Specially Designed Probes to Broaden Transketolase Scope. Simon G, Eljezi T, Legeret B, Charmantray F, Castillo JA ... Amino acid precursors for the detection of transketolase activity in Escherichia coli auxotrophs. ...
Transketolase promotes colorectal cancer metastasis through regulating AKT phosphorylation. Li M, Zhao X, Yong H, Xu J, Qu P, ...
Transketolase (1) * Tuberculosis (1) * Type II NADH:quinone oxidoreductase (1) * Uncoupler (1) ...
PDB Description: Transketolase from Leishmania mexicana. SCOP Domain Sequences for d1r9ja1:. Sequence; same for both SEQRES and ... Protein Transketolase (TK), Pyr module [88736] (4 species). *. Species Leishmania mexicana mexicana [TaxId:44270] [117521] (1 ... d1r9ja1 c.36.1.6 (A:337-526) Transketolase (TK), Pyr module {Leishmania mexicana mexicana} ...
In this work we set out to study the activity of a thermostable Transketolase (TK) from Geobacillus stearothermophilus (TKgst) ... Chiral Polyol Synthesis Catalyzed by a Thermostable Transketolase Immobilized on Layered Double Hydroxides in Ionic liquids. ...
By Jack Kruse,January 23rd, 2020,Series: Hypoxia,Comments Off on HYPOXIA #2: THE HETEROPLASMY BIOMARKER: TRANSKETOLASE ... HYPOXIA #2: THE HETEROPLASMY BIOMARKER: TRANSKETOLASE. Thiamine, also known as vitamin B1, is now known to play a fundamental ...
TransketolaseIBA 01/01/1986 - "Recent data demonstrating normal levels of erythrocyte transketolase in patients presenting with ... 07/01/1999 - "Also discussed are new findings on the molecular genetics of the thiamine-dependent enzyme transketolase in ... 11/01/1986 - "We studied a thiamine-dependent enzyme, transketolase, from fibroblasts of a diabetic patient who developed ... 11/30/1990 - "The relationship between erythrocyte transketolase activity and the TPP effect in Wernickes encephalopathy and ...
Similar to enzyme crystallins of the lens, both aldehyde dehydrogenase and transketolase are thought to contribute to the ... Human corneas possess a remarkably high level of aldehyde dehydrogenase and transketolase. Together, these 2 proteins ...
Protocol and application of basal erythrocyte transketolase activity to improve assessment of thiamine status. Kerry S. Jones, ...
No clinical signs or effects on transketolase activity were seen at the low dose. The authors stated that the toxicity seen in ... Thiamine deficiency was also detected at the high dose, as measured by transketolase activity in red cells. ...
DXP synthase is a thiamine diphosphate-dependent enzyme related to transketolase and the pyruvate dehydrogenase E1-beta subunit ... DXP synthase is a thiamine diphosphate-dependent enzyme related to transketolase and the pyruvate dehydrogenase E1-beta subunit ...
Engineering Transketolase for Industrial Biotechnology. Doctoral thesis , UCL (University College London). Artim-Esen, B; ...
A family of transketolases that directs isoprenoid biosynthesis via a mevalonate-independent pathway. ...
Reaction 1: Transketolase transfers a 2‐carbon unit. * Reaction 2: Transaldolase transfers a 3‐carbon unit. ...
Fold c.48: Transketolase C-terminal domain-like [52921] (1 superfamily). *. Superfamily c.48.1: Transketolase C-terminal domain ...
The activity of transketolase is measured in several steps: (1) the basal activity of transketolase is measured in erythrocytes ... Erythrocyte transketolase activity, markers of cardiac dysfunction and the diagnosis of infantile beriberi. PLoS Negl Trop Dis ... Comparison of erythrocyte transketolase activity with thiamine and thiamine phosphate ester levels in chronic alcoholic ... The most widely used biochemical indicator of thiamine status is the activity of the thiamine-dependent transketolase enzyme in ...
Overexpression of Plastid Transketolase in Tobacco Results in a Thiamine Auxotrophic Phenotype. Plant Cell 27 (2), S. 432 - 447 ...
Overexpression of Plastid Transketolase in Tobacco Results in a Thiamine Auxotrophic Phenotype. Plant Cell 27 (2), pp. 432 - ...
  • Transketolase (abbreviated as TK) is an enzyme that, in humans, is encoded by the TKT gene. (wikipedia.org)
  • The following human genes encode proteins with transketolase activity: TKT (transketolase) TKTL1 (transketolase-like protein 1) TKTL2 (transketolase-like protein 2) The entrance to the active site for this enzyme is made up mainly of several arginine, histidine, serine, and aspartate side-chains, with a glutamate side-chain playing a secondary role. (wikipedia.org)
  • These side-chains, to be specific Arg359, Arg528, His469, and Ser386, are conserved within each transketolase enzyme and interact with the phosphate group of the donor and acceptor substrates. (wikipedia.org)
  • BackgroundPlasmodial transketolase (PTKT) enzyme is one of the novel pharmacological targets being explored as potential anti-malarial drug target due to its functional role and low sequence identity to the human enzyme. (mysciencework.com)
  • Similar to enzyme crystallins of the lens, both aldehyde dehydrogenase and transketolase are thought to contribute to the optical properties of the cornea. (aao.org)
  • DXP synthase is a thiamine diphosphate-dependent enzyme related to transketolase and the pyruvate dehydrogenase E1-beta subunit. (nih.gov)
  • Wernicke-Korsakoff syndrome Symptoms and Signs is caused by a partial deficiency of transketolase, which is an enzyme for the pentose phosphate pathway that requires thiamin as a cofactor. (merckmanuals.com)
  • A stimulation of over 20%-25% during a red blood cell transketolase measurement using thiamine pyrophosphate (TTP) indicates deficiency. (medscape.com)
  • In mammals, transketolase connects the pentose phosphate pathway to glycolysis, feeding excess sugar phosphates into the main carbohydrate metabolic pathways. (wikipedia.org)
  • Protocol and application of basal erythrocyte transketolase activity to improve assessment of thiamine status. (mysciencework.com)
  • The erythrocyte transketolase activity coefficient (ETKac) is a sensitive measure of thiamine status, but its interpretation may be co. (mysciencework.com)
  • Erythrocyte transketolase activity coefficient (ETKAC) assay protocol for the assessment of thiamine status. (mysciencework.com)
  • Erythrocyte transketolase activity is lower in nondialyzed patients than in dialyzed patients. (medscape.com)
  • Engineering Transketolase for Industrial Biotechnology. (ucl.ac.uk)
  • Transketolase is abundantly expressed in the mammalian cornea by the stromal keratocytes and epithelial cells and is reputed to be one of the corneal crystallins. (wikipedia.org)
  • Calcium regulation in chloroplasts and the role of calcium-dependent phosphorylation of transketolase in carbon metabolism. (uni-muenchen.de)
  • DFA mimics ribose in vivo and accumulates in cells following phosphorylation by ribokinase and further metabolism by transketolase. (ca.gov)
  • A functional enzymatic assay of transketolase activity measured before and after the addition of TTP is a more reliable way to measure thiamine nutritional status. (medscape.com)
  • This novel reconstituted transketolase is thermally stable with no loss of activity after incubation for 1 h at 70°C and is stable after 1 h incubation with 50% of the organic solvents methanol, ethanol, isopropanol, DMSO, acetonitrile and acetone. (rcsb.org)
  • Transketolase catalyzes two important reactions, which operate in opposite directions in these two pathways. (wikipedia.org)
  • Moreover, in the Calvin cycle this is the first reaction catalyzed by transketolase, rather than the second. (wikipedia.org)
  • Human transketolase (TKT, EC 2.2.1.1) catalyzes transfers two-carbon units from ketoses (donor) to aldoses (acceptor). (alliedacademies.org)
  • Human corneas possess a remarkably high level of aldehyde dehydrogenase and transketolase. (aao.org)
  • Overexpression of Plastid Transketolase in Tobacco Results in a Thiamine Auxotrophic Phenotype. (mpg.de)
  • RESULTS- Activation of nrf2 by sulforaphane induced nuclear translocation of nrf2 and increased ARE-linked gene expression, for example, three- to fivefold increased expression of transketolase and glutathione reductase. (diabetesjournals.org)
  • Search Transketolase as keywords on MyScienceWork's publications. (mysciencework.com)
  • CONCLUSIONS- We conclude that activation of nrf2 may prevent biochemical dysfunction and related functional responses of endothelial cells induced by hyperglycemia in which increased expression of transketolase has a pivotal role. (diabetesjournals.org)
  • This also abolished the counteracting effect of sulforaphane, suggesting mediation by nrf2 and related increase of transketolase expression. (diabetesjournals.org)
  • The X-ray structure of the holo reconstituted α 2 β 2 tetrameric transketolase has been determined to 1.4 Å resolution. (rcsb.org)
  • The primary outcome measure was 15% change in erythrocyte transketolase activity (ETKA) in group 3. (nature.com)
  • Comparison of Thiamin Diphosphate High-Performance Liquid Chromatography and Erythrocyte Transketolase Assays for Evaluating Thiamin Status in Malaria Patients without Beriberi. (tropmedres.ac)
  • Thiamin status has traditionally been measured through the erythrocyte activation assay (ETKA) or basal transketolase activity (ETK), which indirectly measure thiamin diphosphate (TDP). (tropmedres.ac)
  • The method used to estimate the Recommended Dietary Allowance ( RDA ) for thiamin combines erythrocyte transketolase activity, urinary thiamin excretion, and other findings. (nih.gov)
  • Measuring whole blood or erythrocyte transketolase activity, with and without addition of thiamine diphosphate, is the most reliable method of detecting thiamine deficiency (9). (cdc.gov)
  • Erythrocyte transketolase activity is lower in nondialyzed patients than in dialyzed patients. (medscape.com)
  • Thiamin status is often measured indirectly by assaying the activity of the transketolase enzyme, which depends on TDP, in erythrocyte hemolysates in the presence and absence of added TDP [ 3 ]. (nih.gov)
  • studies have shown a higher risk of thiamin deficiency in people with type 1 and/or type 2 diabetes based on tests of erythrocyte transketolase activity. (wonderlabs.com)
  • I was trained as a graduate student by Charles Singleton with Peter Martin studying the genetics of alcoholism focusing the contributions of the thiamine-requiring enzyme transketolase in the development of Wernicke-Korsakoff syndrome in human alcoholics. (wakehealth.edu)
  • Thiamine and magnesium also serve as co-factors for the cytoplasmic enzyme, transketolase (TK), which catalyses the reversible arm of the Pentose Phosphate Pathway (PPP). (nature.com)
  • May be more effective in controlling damage from diabetes because it is a better activator of the enzyme transketolase. (psychologicalharassment.com)
  • Thiamine (as thiamine pyrophosphate) is important in carbohydrate and amino acid metabolism, forming an essential component of 2-oxoacid dehydrogenases (including pyruvate dehydrogenase and branched chain oxoacid dehydrogenase) and transketolase. (vin.com)
  • Five target proteins were successfully purified from yeast whole cell extract: Transketolase (TKL1), inorganic pyrophosphatase (IPP1), amidotransferase/cyclase HIS7, phosphoglycerate kinase (PGK1) and enolase (ENO1). (uwaterloo.ca)
  • The following human genes encode proteins with transketolase activity: TKT (transketolase) TKTL1 (transketolase-like protein 1) TKTL2 (transketolase-like protein 2) The entrance to the active site for this enzyme is made up mainly of several arginine, histidine, serine, and aspartate side-chains, with a glutamate side-chain playing a secondary role. (wikipedia.org)
  • B-MYB (or MYBL2), Cancerous Inhibitor of PP2A (CIP-2a), and transketolase-like1 (TKTL1). (frontiersin.org)
  • after transfection with anti-TKTL1 siRNA, total transketolase activity dramatically decreases and proliferation was significantly inhibited in cancer cells. (nih.gov)
  • It's also a cofactor to several enzymes that help metabolize carbohydrates, including transketolase and branched-chain α-keto acid dehydrogenase. (purebulk.com)
  • The C-terminal domain of transketolase has been proposed as a regulatory molecule binding site. (nih.gov)
  • Transketolase (abbreviated as TK) is an enzyme that, in humans, is encoded by the TKT gene. (wikipedia.org)
  • In a second case, John Ward of University College London has shown that transketolases and transaminases can be used in a cascade to produce chiral amino diols, and by carrying the different enzymes, all four enantiomers of these ketodiols can be made. (manufacturingchemist.com)
  • These side-chains, to be specific Arg359, Arg528, His469, and Ser386, are conserved within each transketolase enzyme and interact with the phosphate group of the donor and acceptor substrates. (wikipedia.org)