Nitrite Reductase (NAD(P)H)
NADH, NADPH Oxidoreductases
Hydroxymethylglutaryl CoA Reductases
Molecular Sequence Data
Electron Spin Resonance Spectroscopy
Cytochrome c Group
Amino Acid Sequence
Sulfite Reductase (Ferredoxin)
Electron Transport Complex IV
Oxidoreductases Acting on Sulfur Group Donors
Gene Expression Regulation, Bacterial
Quaternary Ammonium Compounds
Methylenetetrahydrofolate Reductase (NADPH2)
Nitrate Reductase (NADH)
Methionine Sulfoxide Reductases
Hydroxymethylglutaryl-CoA Reductase Inhibitors
Ribonucleoside Diphosphate Reductase
Sequence Homology, Amino Acid
Sequence Analysis, DNA
Oxidoreductases Acting on CH-CH Group Donors
Enoyl-(Acyl-Carrier-Protein) Reductase (NADH)
Denitrifying Pseudomonas aeruginosa: some parameters of growth and active transport. (1/435)Optimal cell yield of Pseudomonas aeruginosa grown under denitrifying conditions was obtained with 100 mM nitrate as the terminal electron acceptor, irrespective of the medium used. Nitrite as the terminal electron acceptor supported poor denitrifying growth when concentrations of less than 15 mM, but not higher, were used, apparently owing to toxicity exerted by nitrite. Nitrite accumulated in the medium during early exponential phase when nitrate was the terminal electron acceptor and then decreased to extinction before midexponential phase. The maximal rate of glucose and gluconate transport was supported by 1 mM nitrate or nitrite as the terminal electron acceptor under anaerobic conditions. The transport rate was greater with nitrate than with nitrite as the terminal electron acceptor, but the greatest transport rate was observed under aerobic conditions with oxygen as the terminal electron acceptor. When P. aeruginosa was inoculated into a denitrifying environment, nitrate reductase was detected after 3 h of incubation, nitrite reductase was detected after another 4 h of incubation, and maximal nitrate and nitrite reductase activities peaked together during midexponential phase. The latter coincided with maximal glucose transport activity. (+info)
Molecular characterization of the nitrite-reducing system of Staphylococcus carnosus. (2/435)Characterization of a nitrite reductase-negative Staphylococcus carnosus Tn917 mutant led to the identification of the nir operon, which encodes NirBD, the dissimilatory NADH-dependent nitrite reductase; SirA, the putative oxidase and chelatase, and SirB, the uroporphyrinogen III methylase, both of which are necessary for biosynthesis of the siroheme prosthetic group; and NirR, which revealed no convincing similarity to proteins with known functions. We suggest that NirR is essential for nir promoter activity. In the absence of NirR, a weak promoter upstream of sirA seems to drive transcription of sirA, nirB, nirD, and sirB in the stationary-growth phase. In primer extension experiments one predominant and several weaker transcription start sites were identified in the nir promoter region. Northern blot analyses indicated that anaerobiosis and nitrite are induction factors of the nir operon: cells grown aerobically with nitrite revealed small amounts of full-length transcript whereas cells grown anaerobically with or without nitrite showed large amounts of full-length transcript. Although a transcript is detectable, no nitrite reduction occurs in cells grown aerobically with nitrite, indicating an additional oxygen-controlled step at the level of translation, enzyme folding, assembly, or insertion of prosthetic groups. The nitrite-reducing activity expressed during anaerobiosis is switched off reversibly when the oxygen tension increases, most likely due to competition for electrons with the aerobic respiratory chain. Another gene, nirC, is located upstream of the nir operon. nirC encodes a putative integral membrane-spanning protein of unknown function. A nirC mutant showed no distinct phenotype. (+info)
The GATA factor AreA is essential for chromatin remodelling in a eukaryotic bidirectional promoter. (3/435)The linked niiA and niaD genes of Aspergillus nidulans are transcribed divergently. The expression of these genes is subject to a dual control system. They are induced by nitrate and repressed by ammonium. AreA mediates derepression in the absence of ammonium and NirA supposedly mediates nitrate induction. Out of 10 GATA sites, a central cluster (sites 5-8) is responsible for approximately 80% of the transcriptional activity of the promoter on both genes. We show occupancy in vivo of site 5 by the AreA protein, even under conditions of repression. Sites 5-8 are situated in a pre-set nucleosome-free region. Under conditions of expression, a drastic nucleosomal rearrangement takes place and the positioning of at least five nucleosomes flanking the central region is lost. Remodelling is strictly dependent on the presence of an active areA gene product, and independent from the NirA-specific and essential transcription factor. Thus, nucleosome remodelling is independent from the transcriptional activation of the niiA-niaD promoter. The results presented cast doubts on the role of NirA as the unique transducer of the nitrate induction signal. We demonstrate, for the first time in vivo, that a GATA factor is involved directly in chromatin remodelling. (+info)
Nitrite reductase from Pseudomonas aeruginosa released by antimicrobial agents and complement induces interleukin-8 production in bronchial epithelial cells. (4/435)We have recently reported that nitrite reductase, a bifunctional enzyme located in the periplasmic space of Pseudomonas aeruginosa, could induce interleukin-8 (IL-8) generation in a variety of respiratory cells, including bronchial epithelial cells (K. Oishi et al. Infect. Immun. 65:2648-2655, 1997). In this report, we examined the mode of nitrite reductase (PNR) release from a serum-sensitive strain of live P. aeruginosa cells during in vitro treatment with four different antimicrobial agents or human complement. Bacterial killing of P. aeruginosa by antimicrobial agents induced PNR release and mediated IL-8 production in human bronchial epithelial (BET-1A) cells. Among these agents, imipenem demonstrated rapid killing of P. aeruginosa as well as rapid release of PNR and resulted in the highest IL-8 production. Complement-mediated killing of P. aeruginosa was also associated with PNR release and enhanced IL-8 production. The immunoprecipitates of the aliquots of bacterial culture containing imipenem or complement with anti-PNR immunoglobulin G (IgG) induced twofold-higher IL-8 production than did the immunoprecipitates of the aliquots of bacterial culture with a control IgG. These pieces of evidence confirmed that PNR released in the aliquots of bacterial culture was responsible for IL-8 production in the BET-1A cells. Furthermore, the culture supernatants of the BET-1A cells stimulated with aliquots of bacterial culture containing antimicrobial agents or complement similarly mediated neutrophil migration in vitro. These data support the possibility that a potent inducer of IL-8, PNR, could be released from P. aeruginosa after exposure to antimicrobial agents or complement and contributes to neutrophil migration in the airways during bronchopulmonary infections with P. aeruginosa. (+info)
PCR detection of genes encoding nitrite reductase in denitrifying bacteria. (5/435)Using consensus regions in gene sequences encoding the two forms of nitrite reductase (Nir), a key enzyme in the denitrification pathway, we designed two sets of PCR primers to amplify cd1- and Cu-nir. The primers were evaluated by screening defined denitrifying strains, denitrifying isolates from wastewater treatment plants, and extracts from activated sludge. Sequence relationships of nir genes were also established. The cd1 primers were designed to amplify a 778 to 799-bp region of cd1-nir in the six published sequences. Likewise, the Cu primers amplified a 473-bp region in seven of the eight published Cu-nir sequences. Together, the two sets of PCR primers amplified nir genes in nine species within four genera, as well as in four of the seven sludge isolates. The primers did not amplify genes of nondenitrifying strains. The Cu primers amplified the expected fragment in all 13 sludge samples, but cd1-nir fragments were only obtained in five samples. PCR products of the expected sizes were verified as nir genes after hybridization to DNA probes, except in one case. The sequenced nir fragments were related to other nir sequences, demonstrating that the primers amplified the correct gene. The selected primer sites for Cu-nir were conserved, while broad-range primers targeting conserved regions of cd1-nir seem to be difficult to find. We also report on the existence of Cu-nir in Paracoccus denitrificans Pd1222. (+info)
The blue copper-containing nitrite reductase from Alcaligenes xylosoxidans: cloning of the nirA gene and characterization of the recombinant enzyme. (6/435)The nirA gene encoding the blue dissimilatory nitrite reductase from Alcaligenes xylosoxidans has been cloned and sequenced. To our knowledge, this is the first report of the characterization of a gene encoding a blue copper-containing nitrite reductase. The deduced amino acid sequence exhibits a high degree of similarity to other copper-containing nitrite reductases from various bacterial sources. The full-length protein included a 24-amino-acid leader peptide. The nirA gene was overexpressed in Escherichia coli and was shown to be exported to the periplasm. Purification was achieved in a single step, and analysis of the recombinant Nir enzyme revealed that cleavage of the signal peptide occurred at a position identical to that for the native enzyme isolated from A. xylosoxidans. The recombinant Nir isolated directly was blue and trimeric and, on the basis of electron paramagnetic resonance spectroscopy and metal analysis, possessed only type 1 copper centers. This type 2-depleted enzyme preparation also had a low nitrite reductase enzyme activity. Incubation of the periplasmic fraction with copper sulfate prior to purification resulted in the isolation of an enzyme with a full complement of type 1 and type 2 copper centers and a high specific activity. The kinetic properties of the recombinant enzyme were indistinguishable from those of the native nitrite reductase isolated from A. xylosoxidans. This rapid isolation procedure will greatly facilitate genetic and biochemical characterization of both wild-type and mutant derivatives of this protein. (+info)
Bacterial nitric oxide synthesis. (7/435)The structure-function relationships in nitrite reductases, key enzymes in the dissimilatory denitrification pathway which reduce nitrite to nitric oxide (NO), are reviewed in this paper. The mechanisms of NO production are discussed in detail and special attention is paid to new structural information, such as the high resolution structure of the copper- and heme-containing enzymes from different sources. Finally, some implications relevant to regulation of the steady state levels of NO in denitrifiers are presented. (+info)
Does the reduction of c heme trigger the conformational change of crystalline nitrite reductase? (8/435)The structures of nitrite reductase from Paracoccus denitrificans GB17 (NiR-Pd) and Pseudomonas aeruginosa (NiR-Pa) have been described for the oxidized and reduced state (Fulop, V., Moir, J. W. B., Ferguson, S. J., and Hajdu, J. (1995) Cell 81, 369-377; Nurizzo, D., Silvestrini, M. C., Mathieu, M., Cutruzzola, F., Bourgeois, D., Fulop, V., Hajdu, J., Brunori, M., Tegoni, M., and Cambillau, C. (1997) Structure 5, 1157-1171; Nurizzo, D., Cutruzzola, F., Arese, M., Bourgeois, D., Brunori, M., Cambillau, C. , and Tegoni, M. (1998) Biochemistry 37, 13987-13996). Major conformational rearrangements are observed in the extreme states although they are more substantial in NiR-Pd. The four structures differ significantly in the c heme domains. Upon reduction, a His17/Met106 heme-ligand switch is observed in NiR-Pd together with concerted movements of the Tyr in the distal site of the d1 heme (Tyr10 in NiR-Pa, Tyr25 in NiR-Pd) and of a loop of the c heme domain (56-62 in NiR-Pa, 99-116 in NiR-Pd). Whether the reduction of the c heme, which undergoes the major rearrangements, is the trigger of these movements is the question addressed by our study. This conformational reorganization is not observed in the partially reduced species, in which the c heme is partially or largely (15-90%) reduced but the d1 heme is still oxidized. These results suggest that the d1 heme reduction is likely to be responsible of the movements. We speculate about the mechanistic explanation as to why the opening of the d1 heme distal pocket only occurs upon electron transfer to the d1 heme itself, to allow binding of the physiological substrate NO2- exclusively to the reduced metal center. (+info)
In the medical field, Nitrite Reductases are enzymes that catalyze the reduction of nitrite ions (NO2-) to nitric oxide (NO). Nitric oxide is a signaling molecule that plays a crucial role in various physiological processes, including vasodilation, neurotransmission, and immune function. Nitrite Reductases are found in a variety of organisms, including bacteria, fungi, and plants, and are often used as biomarkers for certain diseases or as therapeutic agents for treating conditions such as erectile dysfunction and cardiovascular disease.
In the medical field, nitrites are compounds that contain the nitrite ion (NO2-). Nitrites are often used as a medication to treat certain types of heart disease, such as angina pectoris, by relaxing the blood vessels and reducing the workload on the heart. They are also used to treat certain types of anemia, such as methemoglobinemia, by converting methemoglobin (a form of hemoglobin that is unable to carry oxygen) back to normal hemoglobin. Nitrites are also used as a preservative in some foods and beverages, and as a chemical in the manufacturing of dyes, explosives, and other products.
In the medical field, Nitrate Reductases are enzymes that catalyze the reduction of nitrate ions (NO3-) to nitrite ions (NO2-). These enzymes are found in a variety of organisms, including bacteria, plants, and animals. In the context of human health, Nitrate Reductases are of particular interest because they play a role in the production of nitric oxide (NO), a molecule that has a number of important physiological functions. Nitric oxide is a potent vasodilator, meaning that it helps to relax and widen blood vessels, which can improve blood flow and lower blood pressure. In addition to their role in nitric oxide production, Nitrate Reductases have also been implicated in a number of other physiological processes, including the regulation of gene expression, the detoxification of harmful substances, and the maintenance of the balance of oxygen and nitrogen in the body. Overall, Nitrate Reductases are an important class of enzymes that play a variety of roles in human health and physiology.
Sodium nitrite is a chemical compound that is commonly used in the medical field as a preservative and color stabilizer in various medical products, including vaccines, injectable drugs, and topical medications. It is also used as a vasodilator, which means that it can help to widen blood vessels and improve blood flow to the heart and other organs. In addition to its medical uses, sodium nitrite is also used in the food industry as a preservative and color enhancer in processed meats such as bacon, ham, and sausage. It is also used in the treatment of cyanide poisoning, as it can convert the toxic cyanide ion into a less toxic compound that can be eliminated from the body. However, it is important to note that sodium nitrite can be toxic in high doses and can cause serious health problems, including methemoglobinemia (a condition in which the blood becomes unable to carry oxygen) and cancer. Therefore, its use in medical products and food products is strictly regulated by government agencies to ensure its safe use.
Ferredoxin-Nitrite Reductase (FNR) is an enzyme that plays a crucial role in the metabolism of nitrite in various organisms, including bacteria, plants, and animals. It catalyzes the reduction of nitrite (NO2-) to nitric oxide (NO) using ferredoxin, a small electron-carrying protein, as a reducing agent. In the medical field, FNR has been studied for its potential role in various diseases, including cancer, cardiovascular disease, and neurodegenerative disorders. For example, some studies have suggested that FNR may play a role in the development of cancer by promoting the production of reactive oxygen species (ROS), which can damage DNA and promote cell proliferation. Other studies have suggested that FNR may be involved in the regulation of blood pressure and the development of cardiovascular disease. Overall, FNR is an important enzyme that plays a critical role in the metabolism of nitrite and has potential implications for various diseases. Further research is needed to fully understand its function and potential therapeutic applications.
Nitrates are a group of compounds that contain the nitrate ion (NO3-). In the medical field, nitrates are commonly used to treat angina (chest pain caused by reduced blood flow to the heart muscle) and high blood pressure (hypertension). They work by relaxing the smooth muscles in blood vessels, which allows blood to flow more easily and reduces the workload on the heart. Nitrates are available in various forms, including tablets, ointments, and sprays. They are usually taken as needed to relieve symptoms, but may also be taken on a regular schedule to prevent angina attacks or lower blood pressure. It is important to note that nitrates can have side effects, such as headache, flushing, and low blood pressure, and should be used under the guidance of a healthcare provider.
Cytochromes a1 are a family of heme-containing proteins that are found in the electron transport chain of mitochondria. They are involved in the transfer of electrons from complex III to complex IV, which is a crucial step in the process of cellular respiration. In the medical field, cytochromes a1 are often studied in the context of diseases such as mitochondrial disorders, where mutations in the genes encoding these proteins can lead to impaired energy production and a range of symptoms. Additionally, cytochromes a1 have been implicated in various forms of cancer, where they may play a role in regulating cell growth and survival.
In the medical field, Nitrate Reductase is an enzyme that plays a crucial role in the metabolism of nitrate, a compound that is commonly found in vegetables and some drinking water sources. Nitrate Reductase catalyzes the reduction of nitrate to nitrite, which is then converted to nitric oxide (NO) by other enzymes in the body. NO is a signaling molecule that plays a vital role in many physiological processes, including vasodilation, blood pressure regulation, and immune function. Nitrate Reductase is therefore important for maintaining proper NO levels in the body, and its activity is regulated by various factors, including dietary intake of nitrate, oxygen levels, and pH. Disruptions in Nitrate Reductase activity can lead to a variety of health problems, including anemia, hypertension, and cardiovascular disease. In some cases, Nitrate Reductase deficiency can be treated with dietary supplements or medications that increase NO production in the body.
Alcaligenes is a genus of Gram-negative bacteria that are commonly found in soil, water, and the gastrointestinal tracts of animals. Some species of Alcaligenes are pathogenic and can cause infections in humans and animals, particularly in wounds and burns. In the medical field, Alcaligenes is often isolated from clinical samples, such as blood, urine, and sputum, and can be identified using various laboratory techniques, including culture and biochemical tests. Some species of Alcaligenes are also used in biotechnology applications, such as the production of enzymes and biofuels.
Alcaligenes faecalis is a gram-negative, rod-shaped bacterium that is commonly found in the human gastrointestinal tract. It is also known to inhabit soil, water, and other environmental sources. In the medical field, A. faecalis is often associated with infections, particularly those of the urinary tract, respiratory tract, and skin. It can also cause endocarditis, an infection of the inner lining of the heart, and sepsis, a life-threatening condition caused by the spread of infection throughout the body. Treatment for A. faecalis infections typically involves the use of antibiotics, although antibiotic resistance is a growing concern.
NADH and NADPH oxidoreductases are enzymes that play a crucial role in the electron transport chain, which is a series of chemical reactions that generate energy in the form of ATP (adenosine triphosphate) in cells. These enzymes are responsible for transferring electrons from NADH (nicotinamide adenine dinucleotide) and NADPH (nicotinamide adenine dinucleotide phosphate) to oxygen, which is then reduced to water. This process is known as oxidative phosphorylation and is a key part of cellular respiration. NADH and NADPH oxidoreductases are found in the inner mitochondrial membrane and are essential for the production of ATP in cells. Mutations in these enzymes can lead to a variety of diseases, including Leigh syndrome, Leber's hereditary optic neuropathy, and chronic granulomatous disease.
Oxidoreductases are a class of enzymes that catalyze redox reactions, which involve the transfer of electrons from one molecule to another. These enzymes play a crucial role in many biological processes, including metabolism, energy production, and detoxification. In the medical field, oxidoreductases are often studied in relation to various diseases and conditions. For example, some oxidoreductases are involved in the metabolism of drugs and toxins, and changes in their activity can affect the efficacy and toxicity of these substances. Other oxidoreductases are involved in the production of reactive oxygen species (ROS), which can cause cellular damage and contribute to the development of diseases such as cancer and aging. Oxidoreductases are also important in the diagnosis and treatment of certain diseases. For example, some oxidoreductases are used as markers of liver disease, and changes in their activity can indicate the severity of the disease. In addition, some oxidoreductases are targets for drugs used to treat diseases such as cancer and diabetes. Overall, oxidoreductases are a diverse and important class of enzymes that play a central role in many biological processes and are the subject of ongoing research in the medical field.
Bacteroidaceae is a family of Gram-negative bacteria that are commonly found in the human gut microbiome. They are known for their ability to break down complex carbohydrates, such as cellulose and pectin, into simpler compounds that can be absorbed by the body. Bacteroidaceae are also important for maintaining the balance of the gut microbiome and preventing the overgrowth of harmful bacteria. In the medical field, Bacteroidaceae are sometimes studied as potential probiotics, which are live bacteria that are believed to have health benefits when consumed in adequate amounts. Some strains of Bacteroidaceae have been shown to have anti-inflammatory properties and may help to prevent certain diseases, such as inflammatory bowel disease and colorectal cancer. However, more research is needed to fully understand the potential health benefits of Bacteroidaceae and to determine the optimal dosage and duration of treatment.
In the medical field, denitrification refers to the process by which bacteria convert nitrate (NO3-) into nitrogen gas (N2) in the absence of oxygen. This process is important in the nitrogen cycle and is carried out by certain types of bacteria, such as denitrifying bacteria, in soil and water environments. In the context of medicine, denitrification may be relevant in certain medical conditions, such as chronic kidney disease, where the body may not be able to effectively remove excess nitrate from the blood. In these cases, denitrification by certain bacteria in the gut may help to reduce the levels of nitrate in the blood and prevent complications. However, denitrification can also have negative effects in certain medical conditions, such as in the case of nitrate poisoning, where excessive amounts of nitrate can be harmful to the body. In these cases, treatment may involve removing the source of nitrate and providing supportive care to manage symptoms.
Cytochromes c1 are a group of electron transport chain proteins that are found in the inner mitochondrial membrane. They are involved in the transfer of electrons from complex III to complex IV in the electron transport chain, which is a series of protein complexes that are responsible for generating ATP (adenosine triphosphate) from the energy produced by cellular respiration. In the medical field, cytochromes c1 are of interest because they play a critical role in the production of energy within cells, and disruptions in their function can lead to a variety of diseases, including cancer, neurodegenerative disorders, and cardiovascular disease.
Azurin is a blue copper protein that is found in various organisms, including bacteria, fungi, and plants. In the medical field, azurin has been studied for its potential therapeutic applications, particularly in the treatment of cancer and neurodegenerative diseases. Azurin has been shown to have anti-cancer properties, as it can induce apoptosis (cell death) in cancer cells. It has also been found to have neuroprotective effects, as it can reduce oxidative stress and inflammation in the brain, which are key factors in the development of neurodegenerative diseases such as Alzheimer's and Parkinson's disease. In addition to its therapeutic potential, azurin has also been used as a research tool to study copper homeostasis and the role of copper in various biological processes.
Cytochromes are a group of heme-containing proteins that are involved in a variety of biological processes, including electron transport, oxygen transport, and metabolism. In the medical field, cytochromes are often studied in the context of their role in diseases such as cancer, cardiovascular disease, and neurodegenerative disorders. Cytochromes are found in the inner mitochondrial membrane and play a key role in the electron transport chain, which is responsible for generating ATP (adenosine triphosphate), the energy currency of the cell. They are also involved in the metabolism of drugs and toxins, and in the regulation of blood pressure. In addition to their role in metabolism and energy production, cytochromes have been implicated in a number of diseases. For example, mutations in certain cytochromes have been linked to inherited forms of cancer, such as breast and ovarian cancer. They have also been implicated in the development of cardiovascular disease, as well as neurodegenerative disorders such as Parkinson's disease and Alzheimer's disease. Overall, cytochromes are an important class of proteins that play a critical role in many biological processes, and their study is of great interest to researchers in the medical field.
Hydroxymethylglutaryl CoA reductases (HMG-CoA reductases) are a class of enzymes that play a critical role in the metabolism of lipids in the body. Specifically, they catalyze the conversion of hydroxymethylglutaryl-CoA (HMG-CoA) to mevalonate, which is a precursor for the synthesis of cholesterol and other isoprenoid compounds. There are two main types of HMG-CoA reductases: HMG-CoA reductase 1 and HMG-CoA reductase 2. HMG-CoA reductase 1 is primarily found in the liver and is responsible for most of the cholesterol synthesis in the body. HMG-CoA reductase 2 is found in other tissues, including the kidneys, adrenal glands, and the small intestine, and is responsible for a smaller amount of cholesterol synthesis. In the medical field, HMG-CoA reductases are important targets for the treatment of hyperlipidemia, a condition characterized by high levels of cholesterol and triglycerides in the blood. Statins, a class of drugs that inhibit HMG-CoA reductase activity, are commonly used to lower cholesterol levels and reduce the risk of cardiovascular disease.
Heme is a complex organic molecule that contains iron and is a vital component of hemoglobin, myoglobin, and other proteins involved in oxygen transport and storage in living organisms. It is also a component of various enzymes involved in metabolism and detoxification processes. In the medical field, heme is often used as a diagnostic tool to detect and monitor certain medical conditions, such as anemia (a deficiency of red blood cells or hemoglobin), liver disease (which can affect heme synthesis), and certain types of cancer (which can produce abnormal heme molecules). Heme is also used in the production of certain medications, such as heme-based oxygen carriers for use in patients with sickle cell disease or other conditions that affect oxygen transport. Additionally, heme is a component of some dietary supplements and is sometimes used to treat certain types of anemia.
Ribonucleotide reductases (RNRs) are a family of enzymes that play a critical role in the biosynthesis of deoxyribonucleotides (dNTPs), which are the building blocks of DNA. RNRs catalyze the conversion of ribonucleotides (rNTPs) to their deoxyribonucleotide counterparts (dNTPs) by removing a phosphate group and reducing the ribose sugar to the deoxyribose form. There are two classes of RNRs: class I and class II. Class I RNRs are found in all organisms and are composed of two subunits: a large subunit (R1) and a small subunit (R2). Class II RNRs are found only in eukaryotes and are composed of four subunits: a large subunit (R1), a small subunit (R2), a third subunit (R3), and a fourth subunit (R4). RNRs are essential for DNA replication and repair, and mutations in the genes encoding RNRs can lead to various diseases, including cancer. In addition, RNRs are also important targets for the development of antiviral and antitumor drugs.
Anaerobiosis is a condition in which an organism cannot survive in the presence of oxygen. In the medical field, anaerobiosis is often associated with infections caused by anaerobic bacteria, which are bacteria that do not require oxygen to grow and survive. These bacteria are commonly found in the human body, particularly in areas such as the mouth, gut, and female reproductive tract, where oxygen levels are low. Anaerobic bacteria can cause a range of infections, including dental caries, periodontitis, and pelvic inflammatory disease. Treatment for anaerobic infections typically involves the use of antibiotics that are effective against anaerobic bacteria.
Dithionite is a chemical compound that is used in various medical applications. It is a reducing agent that can be used to treat certain types of anemia, such as iron-deficiency anemia, by increasing the body's ability to absorb iron from the diet. It is also used as a treatment for certain types of cancer, such as breast cancer and ovarian cancer, by disrupting the growth and spread of cancer cells. In addition, dithionite is used as a preservative in some medical products, such as vaccines and blood products, to prevent the growth of bacteria and other microorganisms.
Nitric oxide (NO) is a colorless, odorless gas that is produced naturally in the body by various cells, including endothelial cells in the lining of blood vessels. It plays a crucial role in the regulation of blood flow and blood pressure, as well as in the immune response and neurotransmission. In the medical field, NO is often studied in relation to cardiovascular disease, as it is involved in the regulation of blood vessel dilation and constriction. It has also been implicated in the pathogenesis of various conditions, including hypertension, atherosclerosis, and heart failure. NO is also used in medical treatments, such as in the treatment of erectile dysfunction, where it is used to enhance blood flow to the penis. It is also used in the treatment of pulmonary hypertension, where it helps to relax blood vessels in the lungs and improve blood flow. Overall, NO is a critical molecule in the body that plays a vital role in many physiological processes, and its study and manipulation have important implications for the treatment of various medical conditions.
In the medical field, copper is a trace element that is essential for various bodily functions. It plays a crucial role in the formation of red blood cells, the maintenance of healthy bones, and the proper functioning of the immune system. Copper is also involved in the metabolism of iron and the production of energy in the body. Copper deficiency can lead to a range of health problems, including anemia, osteoporosis, and impaired immune function. On the other hand, excessive copper intake can be toxic and can cause damage to the liver, kidneys, and other organs. In some medical treatments, copper is used as a component of certain medications, such as antibiotics and antifungal drugs. Copper is also used in medical devices, such as catheters and implants, due to its antimicrobial properties. Overall, copper is an important nutrient in the medical field, and its proper balance is crucial for maintaining good health.
Hydroxylamines are a class of organic compounds that contain a hydroxyl group (-OH) bonded to an amine group (-NH2). They are commonly used as oxidizing agents in various chemical reactions, including the synthesis of pharmaceuticals and the treatment of wastewater. In the medical field, hydroxylamines have been studied for their potential therapeutic applications. For example, hydroxylamine hydrochloride has been used as a vasodilator to treat hypertension and angina pectoris. It works by relaxing blood vessels and improving blood flow to the heart. Hydroxylamines have also been investigated as potential antiviral agents against a variety of viruses, including HIV and influenza. They are thought to work by inhibiting viral replication and preventing the virus from infecting host cells. However, hydroxylamines can also be toxic and have been associated with adverse effects, including respiratory distress, nausea, and vomiting. Therefore, their use in the medical field is carefully regulated and monitored to ensure their safety and efficacy.
Glutathione Reductase is an enzyme that plays a crucial role in the antioxidant defense system of cells. It catalyzes the reduction of glutathione (GSH) to glutathione disulfide (GSSG) using nicotinamide adenine dinucleotide phosphate (NADPH) as a reducing agent. This reaction is important because GSH is a powerful antioxidant that helps to neutralize reactive oxygen species (ROS) and protect cells from oxidative damage. Glutathione Reductase is found in many tissues throughout the body, including the liver, kidneys, and lungs, and is essential for maintaining cellular health and preventing disease.
FMN Reductase is an enzyme that plays a crucial role in the metabolism of flavin mononucleotide (FMN), a cofactor involved in various cellular processes. FMN Reductase catalyzes the reduction of FMN to flavin adenine dinucleotide (FAD), which is another important cofactor used in many metabolic reactions. In the medical field, FMN Reductase is of interest because it is involved in the metabolism of several drugs and toxins, including the antibiotic rifampicin and the carcinogen benzo[a]pyrene. Mutations in the gene encoding FMN Reductase have been associated with certain genetic disorders, such as Friedreich's ataxia, a neurodegenerative disease characterized by progressive loss of coordination and balance. In addition, FMN Reductase has been studied as a potential target for the development of new drugs for the treatment of various diseases, including cancer, infectious diseases, and neurological disorders.
Thioredoxin-disulfide reductase (TDR) is an enzyme that plays a crucial role in the regulation of cellular redox homeostasis. It catalyzes the reduction of disulfide bonds in proteins, which are important for maintaining the proper structure and function of many proteins in the cell. TDR is involved in a variety of cellular processes, including protein folding, signal transduction, and antioxidant defense. In the medical field, TDR is of interest because it has been implicated in a number of diseases, including cancer, neurodegenerative disorders, and cardiovascular disease. Understanding the role of TDR in these diseases may lead to the development of new therapeutic strategies.
Nitrous oxide, also known as laughing gas, is a colorless, odorless gas that is commonly used in the medical field as an anesthetic and analgesic. It is a potent analgesic, meaning it can help to reduce pain and discomfort during medical procedures, and it is also a sedative, meaning it can help to calm and relax patients. In medical settings, nitrous oxide is typically administered through a mask that covers the patient's nose and mouth. The gas is mixed with oxygen and inhaled by the patient, which helps to produce a feeling of relaxation and euphoria. Nitrous oxide is often used in combination with other anesthetics, such as local anesthetics or general anesthesia, to provide a more complete and effective anesthetic. Nitrous oxide is considered to be a relatively safe anesthetic, with few side effects. However, it can cause dizziness, lightheadedness, and nausea in some patients, and it can also cause a temporary decrease in blood pressure. As with any anesthetic, it is important for patients to follow their doctor's instructions carefully and to report any side effects or concerns to their healthcare provider.
NADPH-Ferrihemoprotein Reductase, also known as NR5A1, is an enzyme that plays a crucial role in the metabolism of iron in the body. It is responsible for reducing ferrihemoprotein (Fe3+) to ferrous hemoprotein (Fe2+), which is an essential step in the absorption and transport of iron in the body. NR5A1 is primarily expressed in the liver, small intestine, and bone marrow, where it is involved in the regulation of iron homeostasis. It is also involved in the metabolism of other metals, such as copper and zinc. Deficiency or dysfunction of NR5A1 can lead to iron deficiency anemia, a condition characterized by low levels of iron in the body, which can cause fatigue, weakness, and other symptoms. It can also lead to other metabolic disorders, such as copper deficiency and zinc deficiency. In the medical field, NADPH-Ferrihemoprotein Reductase is an important target for the development of new treatments for iron deficiency anemia and other metabolic disorders.
Ferredoxins are small, soluble electron transfer proteins that play a crucial role in cellular respiration and photosynthesis. They are found in a wide range of organisms, including bacteria, plants, and animals. In the context of cellular respiration, ferredoxins are involved in the transfer of electrons from one molecule to another, ultimately leading to the production of ATP (adenosine triphosphate), the energy currency of the cell. They are also involved in the detoxification of harmful molecules, such as hydrogen peroxide. In photosynthesis, ferredoxins are involved in the transfer of electrons from water to carbon dioxide, ultimately leading to the production of glucose and oxygen. They are also involved in the regulation of photosynthesis by controlling the flow of electrons through the photosynthetic electron transport chain. Ferredoxins are typically composed of four to eight alpha-helices and have a molecular weight of around 10-15 kDa. They are often found in association with other proteins, such as ferredoxin reductases, which are involved in the reduction of ferredoxins to their reduced form.
Ferredoxin-NADP reductase (FNR) is an enzyme that plays a crucial role in the electron transport chain of photosynthesis and respiration in plants, algae, and some bacteria. It catalyzes the transfer of electrons from ferredoxin, a small iron-sulfur protein, to NADP+ (nicotinamide adenine dinucleotide phosphate), reducing it to NADPH (nicotinamide adenine dinucleotide phosphate hydrogen). In photosynthesis, FNR is involved in the light-dependent reactions, where it receives electrons from the photosystem I complex and passes them on to the photosystem II complex, which uses them to split water molecules and produce oxygen. In respiration, FNR is involved in the light-independent reactions, where it receives electrons from the cytochrome b6f complex and passes them on to the NADP+ pool, which is used in the Calvin cycle to fix carbon dioxide into organic compounds. FNR is a key enzyme in the regulation of photosynthesis and respiration, and its activity is influenced by various factors such as light intensity, temperature, and nutrient availability. Mutations in the FNR gene can lead to defects in photosynthesis and respiration, which can affect plant growth and development.
Hydroxylamine is a chemical compound with the formula NH2OH. It is a colorless, highly toxic gas that is used in various industrial applications, including the production of dyes, pharmaceuticals, and explosives. In the medical field, hydroxylamine is not commonly used. However, it has been studied for its potential as an antiviral agent against certain viruses, including HIV and influenza. It is also used as a reagent in analytical chemistry for the determination of certain compounds.
Amyl nitrite is a medication that is used to treat angina (chest pain) and to lower blood pressure in people with heart disease. It works by relaxing the blood vessels and increasing blood flow to the heart. Amyl nitrite is usually administered as a nasal spray and is used on an as-needed basis. It is not a long-term treatment for heart disease and should not be used to treat chest pain that is not related to angina. Amyl nitrite can cause side effects such as headache, flushing, and dizziness. It should not be used by people who are allergic to nitrites or who have certain types of heart disease.
In the medical field, the term "Cytochrome c Group" refers to a family of heme-containing proteins that are involved in electron transfer reactions in the mitochondria of cells. These proteins play a crucial role in the electron transport chain, which is responsible for generating ATP, the energy currency of the cell. Cytochrome c is a small, water-soluble protein that is released from the mitochondria during apoptosis, a programmed cell death process. The release of cytochrome c from the mitochondria is a key event in the initiation of apoptosis, and it has been implicated in a number of diseases, including cancer, neurodegenerative disorders, and cardiovascular disease. Other members of the cytochrome c group include cytochrome b, cytochrome c1, and cytochrome oxidase. These proteins work together to transfer electrons from one molecule to another, ultimately leading to the reduction of oxygen to water. Any disruption in the function of these proteins can lead to a buildup of reactive oxygen species, which can damage cellular components and contribute to disease.
Cytochrome reductases are a group of enzymes that play a crucial role in the electron transport chain, which is a series of chemical reactions that generate energy in the form of ATP (adenosine triphosphate) in cells. These enzymes are responsible for transferring electrons from electron donors to electron acceptors, such as cytochromes, and are found in the inner mitochondrial membrane in eukaryotic cells and in the plasma membrane in prokaryotic cells. Cytochrome reductases are involved in a variety of metabolic processes, including the breakdown of fatty acids, the synthesis of cholesterol, and the detoxification of harmful substances. They are also important in the production of reactive oxygen species (ROS), which can damage cells and contribute to the development of various diseases, including cancer and neurodegenerative disorders. In the medical field, cytochrome reductases are the target of several drugs, including statins, which are used to lower cholesterol levels, and anticancer drugs, which target the enzymes to disrupt the electron transport chain and kill cancer cells.
Bacterial proteins are proteins that are synthesized by bacteria. They are essential for the survival and function of bacteria, and play a variety of roles in bacterial metabolism, growth, and pathogenicity. Bacterial proteins can be classified into several categories based on their function, including structural proteins, metabolic enzymes, regulatory proteins, and toxins. Structural proteins provide support and shape to the bacterial cell, while metabolic enzymes are involved in the breakdown of nutrients and the synthesis of new molecules. Regulatory proteins control the expression of other genes, and toxins can cause damage to host cells and tissues. Bacterial proteins are of interest in the medical field because they can be used as targets for the development of antibiotics and other antimicrobial agents. They can also be used as diagnostic markers for bacterial infections, and as vaccines to prevent bacterial diseases. Additionally, some bacterial proteins have been shown to have therapeutic potential, such as enzymes that can break down harmful substances in the body or proteins that can stimulate the immune system.
Aerobiosis is a type of respiration that occurs in the presence of oxygen. In the medical field, aerobiosis is the process by which cells in the body use oxygen to produce energy through a series of chemical reactions called cellular respiration. This process is essential for the survival of most living organisms, as it provides the energy needed for growth, repair, and other vital functions. During aerobiosis, glucose (a type of sugar) is broken down into carbon dioxide and water, releasing energy in the form of ATP (adenosine triphosphate), which is the primary energy currency of the cell. Oxygen is required for this process to occur, as it acts as the final electron acceptor in the electron transport chain, which is the final step in cellular respiration. Aerobic exercise, such as running or cycling, is a type of physical activity that relies on aerobiosis to produce energy. During aerobic exercise, the body uses oxygen to break down glucose and other nutrients, producing energy that can be used to power the muscles and other organs. Regular aerobic exercise has been shown to have numerous health benefits, including improved cardiovascular health, increased endurance, and weight loss.
In the medical field, an amino acid sequence refers to the linear order of amino acids in a protein molecule. Proteins are made up of chains of amino acids, and the specific sequence of these amino acids determines the protein's structure and function. The amino acid sequence is determined by the genetic code, which is a set of rules that specifies how the sequence of nucleotides in DNA is translated into the sequence of amino acids in a protein. Each amino acid is represented by a three-letter code, and the sequence of these codes is the amino acid sequence of the protein. The amino acid sequence is important because it determines the protein's three-dimensional structure, which in turn determines its function. Small changes in the amino acid sequence can have significant effects on the protein's structure and function, and this can lead to diseases or disorders. For example, mutations in the amino acid sequence of a protein involved in blood clotting can lead to bleeding disorders.
Electron Transport Complex IV, also known as cytochrome c oxidase, is a protein complex located in the inner mitochondrial membrane that plays a crucial role in cellular respiration. It is the final enzyme in the electron transport chain, which is responsible for generating ATP, the energy currency of the cell. During cellular respiration, electrons are passed through a series of protein complexes in the electron transport chain, releasing energy that is used to pump protons across the inner mitochondrial membrane. This creates a proton gradient that is used to drive the synthesis of ATP by ATP synthase. Electron Transport Complex IV is unique among the other electron transport chain complexes in that it not only pumps protons but also accepts electrons from cytochrome c and transfers them to molecular oxygen, which is reduced to water. This process is the final step in the electron transport chain and is essential for the production of ATP. Disruptions in the function of Electron Transport Complex IV can lead to a variety of medical conditions, including mitochondrial disorders, neurodegenerative diseases, and certain types of cancer.
Tetrahydrofolate dehydrogenase (THD) is an enzyme that plays a crucial role in the metabolism of folate, a B-vitamin that is essential for the synthesis of DNA, RNA, and amino acids. THD catalyzes the conversion of tetrahydrofolate (THF) to dihydrofolate (DHF), which is a key intermediate in the one-carbon transfer reactions that are necessary for the biosynthesis of nucleotides and amino acids. In the medical field, THD deficiency can lead to a range of health problems, including anemia, megaloblastic anemia, and neural tube defects. THD deficiency can be caused by genetic mutations that affect the enzyme's structure or function, or by nutritional deficiencies of folate or its precursors. Treatment for THD deficiency typically involves supplementation with folate or its precursors, as well as management of any underlying medical conditions.
Oxidoreductases Acting on Sulfur Group Donors (EC 1.8.1) are a group of enzymes that catalyze the transfer of electrons from a sulfur-containing donor molecule to an acceptor molecule. These enzymes play important roles in various biological processes, including the metabolism of sulfur-containing amino acids, the detoxification of reactive sulfur species, and the biosynthesis of sulfur-containing compounds such as coenzyme A and glutathione. In the medical field, these enzymes are of particular interest because they are involved in the metabolism of drugs and other xenobiotics that contain sulfur groups. For example, some drugs are metabolized by oxidoreductases acting on sulfur group donors, which can affect their efficacy and toxicity. In addition, these enzymes are also involved in the metabolism of endogenous compounds such as hydrogen sulfide, which has been implicated in various physiological and pathological processes. Overall, understanding the function and regulation of oxidoreductases acting on sulfur group donors is important for developing new drugs and therapies, as well as for understanding the underlying mechanisms of various diseases and disorders.
In the medical field, nitrogen is a chemical element that is commonly used in various medical applications. Nitrogen is a non-metallic gas that is essential for life and is found in the air we breathe. It is also used in the production of various medical gases, such as nitrous oxide, which is used as an anesthetic during medical procedures. Nitrogen is also used in the treatment of certain medical conditions, such as nitrogen narcosis, which is a condition that occurs when a person breathes compressed air that contains high levels of nitrogen. Nitrogen narcosis can cause symptoms such as dizziness, confusion, and disorientation, and it is typically treated by reducing the amount of nitrogen in the air that the person is breathing. In addition, nitrogen is used in the production of various medical devices and equipment, such as medical imaging equipment and surgical instruments. It is also used in the production of certain medications, such as nitroglycerin, which is used to treat heart conditions. Overall, nitrogen plays an important role in the medical field and is used in a variety of medical applications.
Quaternary ammonium compounds (QACs) are a class of cationic compounds that consist of a central nitrogen atom bonded to four alkyl or aryl groups, with one of the alkyl groups replaced by a positively charged ammonium ion. In the medical field, QACs are commonly used as disinfectants, antiseptics, and preservatives due to their broad-spectrum antimicrobial activity against bacteria, viruses, fungi, and algae. QACs work by disrupting the cell membrane of microorganisms, leading to cell lysis and death. They are particularly effective against Gram-positive bacteria, which have a thick peptidoglycan layer that can be penetrated by the positively charged ammonium ion. QACs are also effective against enveloped viruses, such as influenza and herpes, by disrupting the viral envelope. QACs are used in a variety of medical applications, including as disinfectants for surfaces and equipment, antiseptics for skin and wound care, and preservatives for pharmaceuticals and medical devices. However, QACs can also be toxic to humans and other animals if ingested or inhaled in high concentrations. Therefore, proper handling and use of QACs are essential to minimize the risk of adverse effects.
Achromobacter denitrificans is a gram-negative, rod-shaped bacterium that belongs to the family Alcaligenaceae. It is a common inhabitant of soil and water, and can also be found in the respiratory tracts of humans and animals. In the medical field, Achromobacter denitrificans is known to cause a variety of infections, including pneumonia, sepsis, and urinary tract infections. It is also associated with nosocomial infections, which are infections that are acquired in a hospital or healthcare setting. Achromobacter denitrificans is resistant to many antibiotics, including penicillin, cephalosporins, and aminoglycosides. Treatment of infections caused by this bacterium typically involves the use of broad-spectrum antibiotics, such as carbapenems or quinolones. It is important to note that Achromobacter denitrificans is not a common pathogen, and infections caused by this bacterium are typically associated with individuals who have weakened immune systems or who are receiving long-term antibiotic therapy.
In the medical field, a base sequence refers to the specific order of nucleotides (adenine, thymine, cytosine, and guanine) that make up the genetic material (DNA or RNA) of an organism. The base sequence determines the genetic information encoded within the DNA molecule and ultimately determines the traits and characteristics of an individual. The base sequence can be analyzed using various techniques, such as DNA sequencing, to identify genetic variations or mutations that may be associated with certain diseases or conditions.
Benzyl viologen is a chemical compound that is used as a photosensitizer in photodynamic therapy (PDT) for the treatment of various medical conditions, including cancer, psoriasis, and age-related macular degeneration (AMD). PDT involves the use of a photosensitizer, such as benzyl viologen, which is administered to the patient and then activated by a specific wavelength of light. The activated photosensitizer generates reactive oxygen species that can damage cancer cells or other diseased cells, while leaving healthy cells relatively unharmed. Benzyl viologen has been shown to be effective in destroying cancer cells in vitro and in animal models, and is currently being investigated for use in clinical trials for the treatment of various types of cancer.
Ammonia is a chemical compound with the formula NH3. It is a colorless, pungent gas with a strong, unpleasant odor. In the medical field, ammonia is often used as a diagnostic tool to test for liver and kidney function. High levels of ammonia in the blood can be a sign of liver or kidney disease, as well as certain genetic disorders such as urea cycle disorders. Ammonia can also be used as a treatment for certain conditions, such as metabolic acidosis, which is a condition in which the body produces too much acid. However, ammonia can be toxic in high concentrations and can cause respiratory and neurological problems if inhaled or ingested.
NADP stands for Nicotinamide Adenine Dinucleotide Phosphate. It is a coenzyme that plays a crucial role in various metabolic processes in the body, including the metabolism of carbohydrates, fats, and proteins. NADP is involved in the conversion of glucose to glycogen, the breakdown of fatty acids, and the synthesis of amino acids. It is also involved in the process of photosynthesis in plants, where it acts as a carrier of electrons. In the medical field, NADP is often used as a supplement to support various metabolic processes and to enhance energy production in the body.
Iron-sulfur proteins are a class of proteins that contain iron and sulfur atoms as prosthetic groups. These proteins are involved in a wide range of biological processes, including electron transfer, oxygen transport, and catalysis. They are found in all domains of life, from bacteria to humans, and play important roles in many cellular processes, such as photosynthesis, respiration, and metabolism. Iron-sulfur proteins are also involved in the regulation of gene expression and the detoxification of harmful molecules. They are an important class of proteins that play a critical role in maintaining cellular health and function.
Sulfites are compounds that contain the sulfur ion (S2-) and are commonly used as preservatives in food and beverages. They are also used in the production of certain drugs and as a bleaching agent in textiles. In the medical field, sulfites can cause allergic reactions in some people, particularly those with sulfite sensitivity or asthma. Symptoms of a sulfite allergy can include hives, itching, difficulty breathing, and anaphylaxis, which is a severe and potentially life-threatening allergic reaction. Sulfites are also used as a treatment for certain medical conditions, such as rheumatoid arthritis and psoriasis. In these cases, sulfites are administered in low doses and are closely monitored by a healthcare provider to ensure their safety and effectiveness. Overall, sulfites have both medical and non-medical uses, and their effects can vary depending on the individual and the context in which they are used.
Hemeproteins are a class of proteins that contain a heme group, which is a complex of iron and porphyrin. Hemeproteins are found in many organisms and play important roles in a variety of biological processes, including oxygen transport, energy metabolism, and detoxification. The most well-known hemeprotein is hemoglobin, which is found in red blood cells and is responsible for carrying oxygen from the lungs to the body's tissues. Hemoglobin is composed of four subunits, each of which contains a heme group. The iron atom in the heme group can bind to oxygen molecules, allowing hemoglobin to transport oxygen throughout the body. Other examples of hemeproteins include myoglobin, which is found in muscle tissue and stores oxygen for use during periods of high physical activity, and cytochrome P450 enzymes, which are involved in the metabolism of drugs and other xenobiotics. Hemeproteins are important for many biological processes and are the subject of ongoing research in the medical field.
Methionine sulfoxide reductases (MSRs) are a family of enzymes that play a crucial role in the repair of oxidatively damaged methionine residues in proteins. These enzymes catalyze the reduction of methionine sulfoxide (MetO) back to methionine (Met), which is the biologically active form of the amino acid. In the medical field, MSRs have been implicated in a variety of diseases and conditions, including neurodegenerative disorders, cancer, and aging. For example, decreased activity of certain MSRs has been associated with the accumulation of MetO in proteins, which can lead to protein misfolding and aggregation. This has been implicated in the pathogenesis of diseases such as Alzheimer's and Parkinson's disease. MSRs are also being studied as potential therapeutic targets for these and other diseases. For example, drugs that enhance the activity of MSRs have been shown to improve cognitive function in animal models of Alzheimer's disease, and to inhibit the growth of cancer cells in vitro. Overall, MSRs are important enzymes that play a critical role in maintaining protein function and preventing disease.
Ribonucleoside diphosphate reductase (RNR) is an enzyme that plays a critical role in the biosynthesis of deoxyribonucleotides (dNTPs), which are the building blocks of DNA. RNR catalyzes the conversion of ribonucleoside diphosphates (NDPs) to deoxyribonucleoside diphosphates (dNDPs) by removing a phosphate group and adding a deoxyribose sugar moiety. There are two types of RNR enzymes: class I and class II. Class I RNR is found in prokaryotes and some eukaryotes, while class II RNR is found in all eukaryotes. Both classes of RNR are essential for DNA synthesis and repair, and mutations in the genes encoding these enzymes can lead to various diseases, including cancer. In the medical field, RNR is an important target for cancer therapy. Many cancer cells have high levels of RNR activity, which is necessary for their rapid proliferation. By inhibiting RNR, it is possible to disrupt DNA synthesis and kill cancer cells. Several drugs, including ribavirin and fludarabine, are used in the treatment of cancer and other diseases by targeting RNR.
In the medical field, binding sites refer to specific locations on the surface of a protein molecule where a ligand (a molecule that binds to the protein) can attach. These binding sites are often formed by a specific arrangement of amino acids within the protein, and they are critical for the protein's function. Binding sites can be found on a wide range of proteins, including enzymes, receptors, and transporters. When a ligand binds to a protein's binding site, it can cause a conformational change in the protein, which can alter its activity or function. For example, a hormone may bind to a receptor protein, triggering a signaling cascade that leads to a specific cellular response. Understanding the structure and function of binding sites is important in many areas of medicine, including drug discovery and development, as well as the study of diseases caused by mutations in proteins that affect their binding sites. By targeting specific binding sites on proteins, researchers can develop drugs that modulate protein activity and potentially treat a wide range of diseases.
Dihydropteridine reductase (DHPR) is an enzyme that plays a crucial role in the metabolism of the amino acid tryptophan and the synthesis of the cofactors tetrahydrobiopterin (BH4) and dihydrobiopterin (BH2). These cofactors are essential for the proper functioning of several enzymes involved in the metabolism of neurotransmitters, such as dopamine, serotonin, and norepinephrine. DHPR catalyzes the reduction of dihydrobiopterin to tetrahydrobiopterin, which is a critical step in the biosynthesis of BH4. BH4 is a cofactor for the enzymes that synthesize and degrade neurotransmitters, and its deficiency can lead to a range of neurological disorders, including phenylketonuria (PKU), homocystinuria, and hyperphenylalaninemia. DHPR is encoded by the QDPR gene, and mutations in this gene can cause a rare inherited disorder called dihydropteridine reductase deficiency (DHPRD). DHPRD is characterized by severe neurological symptoms, including intellectual disability, seizures, and movement disorders.
Cytochromes c2 are a family of electron transfer proteins that are found in the inner mitochondrial membrane. They are involved in the electron transport chain, which is a series of protein complexes that transfer electrons from one molecule to another, ultimately leading to the production of ATP (adenosine triphosphate), the energy currency of the cell. Cytochromes c2 are important for the proper functioning of the electron transport chain and the production of ATP. They are also involved in the regulation of cellular metabolism and the response to oxidative stress. In the medical field, cytochromes c2 are studied in relation to a variety of diseases, including cancer, neurodegenerative disorders, and cardiovascular disease.
In the medical field, oxygen is a gas that is essential for the survival of most living organisms. It is used to treat a variety of medical conditions, including respiratory disorders, heart disease, and anemia. Oxygen is typically administered through a mask, nasal cannula, or oxygen tank, and is used to increase the amount of oxygen in the bloodstream. This can help to improve oxygenation of the body's tissues and organs, which is important for maintaining normal bodily functions. In medical settings, oxygen is often used to treat patients who are experiencing difficulty breathing due to conditions such as pneumonia, chronic obstructive pulmonary disease (COPD), or asthma. It may also be used to treat patients who have suffered from a heart attack or stroke, as well as those who are recovering from surgery or other medical procedures. Overall, oxygen is a critical component of modern medical treatment, and is used in a wide range of clinical settings to help patients recover from illness and maintain their health.
Cloning, molecular, in the medical field refers to the process of creating identical copies of a specific DNA sequence or gene. This is achieved through a technique called polymerase chain reaction (PCR), which amplifies a specific DNA sequence to produce multiple copies of it. Molecular cloning is commonly used in medical research to study the function of specific genes, to create genetically modified organisms for therapeutic purposes, and to develop new drugs and treatments. It is also used in forensic science to identify individuals based on their DNA. In the context of human cloning, molecular cloning is used to create identical copies of a specific gene or DNA sequence from one individual and insert it into the genome of another individual. This technique has been used to create transgenic animals, but human cloning is currently illegal in many countries due to ethical concerns.
Quinone reductases are a group of enzymes that play a crucial role in the metabolism of quinones, a class of compounds that are found in many natural products and are also produced as byproducts of cellular metabolism. These enzymes are responsible for reducing quinones to hydroquinones, which are less reactive and less toxic than their quinone counterparts. There are several different types of quinone reductases, including NAD(P)H:quinone oxidoreductase 1 (NQO1), which is found in many tissues throughout the body, and DT-diaphorase (DTD), which is primarily found in the liver and kidneys. These enzymes are important for protecting cells from damage caused by reactive oxygen species, which are produced as byproducts of cellular metabolism and can cause oxidative stress and damage to cellular components. In the medical field, quinone reductases are of interest because they have been shown to play a role in the development and progression of a number of diseases, including cancer, cardiovascular disease, and neurodegenerative disorders. For example, NQO1 has been shown to play a role in the metabolism of certain cancer drugs, and its activity has been linked to the development of resistance to these drugs. DTD has been shown to play a role in the metabolism of environmental toxins, and its activity has been linked to the development of certain types of cancer and other diseases. Overall, quinone reductases are important enzymes that play a crucial role in the metabolism of quinones and the protection of cells from damage caused by reactive oxygen species. Their activity is of interest in the medical field because of their potential role in the development and progression of a number of diseases.
Metalloproteins are proteins that contain one or more metal ions as a cofactor. These metal ions play a crucial role in the structure and function of the protein. Metalloproteins are involved in a wide range of biological processes, including catalysis, electron transfer, and structural support. Examples of metalloproteins include hemoglobin, which contains iron and is responsible for oxygen transport in the blood, and cytochrome c, which contains heme and is involved in electron transfer in the electron transport chain. Metalloproteins can be classified based on the type of metal ion they contain, such as iron, copper, zinc, magnesium, or calcium. The metal ion can be bound to the protein through coordination bonds with amino acid side chains or other ligands. In the medical field, metalloproteins are important targets for drug discovery and development. For example, drugs that target metalloproteins involved in cancer, inflammation, or neurodegenerative diseases are being actively researched. Additionally, metalloproteins are also important for understanding the mechanisms of diseases and developing diagnostic and therapeutic strategies.
Thiosulfates are a class of compounds that contain a sulfur-oxygen-sulfur (SOS) group. In the medical field, thiosulfates are used as antioxidants and have been studied for their potential therapeutic effects in various conditions, including cancer, cardiovascular disease, and neurodegenerative disorders. One of the most well-known thiosulfates is sodium thiosulfate, which is used as a contrast agent in radiographic imaging procedures. It is also used as a treatment for cyanide poisoning, as it binds to cyanide and forms a less toxic compound that can be eliminated from the body. Other thiosulfates, such as calcium thiosulfate and magnesium thiosulfate, have been studied for their potential anti-inflammatory and anti-cancer effects. They have been shown to inhibit the growth of cancer cells and reduce inflammation in animal models of various diseases. Overall, thiosulfates have a diverse range of potential therapeutic applications in the medical field, and ongoing research is exploring their potential uses in various conditions.
Alcohol oxidoreductases are a group of enzymes that catalyze the oxidation of alcohols. In the medical field, these enzymes are of particular interest because they play a key role in the metabolism of alcohol in the body. There are several different types of alcohol oxidoreductases, including alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH). ADH is responsible for converting alcohol (ethanol) into acetaldehyde, a toxic substance that can cause a range of symptoms when present in high concentrations, including headache, nausea, and dizziness. ALDH is responsible for converting acetaldehyde into acetate, a non-toxic substance that can be further metabolized by the body. Alcohol oxidoreductases are found in a variety of tissues throughout the body, including the liver, brain, and lungs. In the liver, ADH and ALDH are particularly important for metabolizing alcohol, as this organ is responsible for processing a large amount of the alcohol that is consumed. Disruptions in the activity of alcohol oxidoreductases can lead to a range of health problems, including alcohol dependence, liver disease, and certain types of cancer. For example, individuals who are unable to effectively metabolize alcohol due to a deficiency in ADH or ALDH may be more susceptible to the negative effects of alcohol consumption, such as liver damage and addiction.
Simazine is a herbicide that is used to control broadleaf weeds and grasses in crops such as corn, sorghum, and soybeans. It works by inhibiting the growth of plants by interfering with their ability to absorb nutrients from the soil. Simazine is typically applied as a pre-emergent herbicide, meaning it is applied before the weeds emerge from the soil. It is also used as a post-emergent herbicide, applied after the weeds have emerged. Simazine is considered to be relatively safe for humans and animals, but it can be toxic to fish and other aquatic organisms. It is important to follow all label instructions and safety precautions when using simazine.
Oxidoreductases Acting on CH-CH Group Donors are a group of enzymes that catalyze the transfer of hydrogen atoms from one molecule to another, with the CH-CH group acting as the donor. These enzymes are involved in a variety of biological processes, including the metabolism of fatty acids, the synthesis of cholesterol and other lipids, and the detoxification of harmful substances. In the medical field, these enzymes are often studied in the context of diseases related to lipid metabolism, such as obesity, diabetes, and cardiovascular disease. They are also important in the development of new drugs for the treatment of these conditions.
Flavins are a group of organic compounds that are important in various biological processes, including metabolism and energy production. In the medical field, flavins are often studied for their potential therapeutic applications, particularly in the treatment of diseases related to oxidative stress and inflammation. There are two main types of flavins: flavin mononucleotide (FMN) and flavin adenine dinucleotide (FAD). FMN and FAD are both derivatives of riboflavin, a water-soluble vitamin that is essential for human health. FMN and FAD are involved in a wide range of biological processes, including the metabolism of carbohydrates, fats, and proteins, as well as the production of energy in the form of ATP. In addition to their metabolic functions, flavins also play a role in protecting cells from oxidative stress and inflammation. This is because flavins can act as antioxidants, neutralizing harmful molecules called free radicals that can damage cells and contribute to the development of diseases such as cancer, heart disease, and neurodegenerative disorders. Overall, flavins are an important class of compounds in the medical field, with potential applications in the treatment of a wide range of diseases and conditions.
In the medical field, catalysis refers to the acceleration of a chemical reaction by a catalyst. A catalyst is a substance that increases the rate of a chemical reaction without being consumed or altered in the process. Catalysts are commonly used in medical research and drug development to speed up the synthesis of compounds or to optimize the efficiency of chemical reactions. For example, enzymes are biological catalysts that play a crucial role in many metabolic processes in the body. In medical research, enzymes are often used as catalysts to speed up the synthesis of drugs or to optimize the efficiency of chemical reactions involved in drug metabolism. Catalysis is also used in medical imaging techniques, such as magnetic resonance imaging (MRI), where contrast agents are used to enhance the visibility of certain tissues or organs. These contrast agents are often synthesized using catalytic reactions to increase their efficiency and effectiveness. Overall, catalysis plays a critical role in many areas of medical research and drug development, helping to accelerate the synthesis of compounds and optimize the efficiency of chemical reactions.
Paraquat is a highly toxic herbicide that is commonly used in agriculture to kill weeds and grasses. It is a non-selective herbicide, meaning that it kills all types of plants, including crops. Paraquat is typically applied as a spray to the leaves of plants, and it works by disrupting the plant's ability to produce energy through photosynthesis. In the medical field, paraquat is not typically used as a treatment for any medical condition. However, paraquat is sometimes used as a suicide poison, and exposure to paraquat can be fatal. Paraquat poisoning can cause a range of symptoms, including shortness of breath, coughing, chest pain, nausea, vomiting, diarrhea, and abdominal pain. In severe cases, paraquat poisoning can lead to respiratory failure and death. Treatment for paraquat poisoning typically involves supportive care, such as oxygen therapy, fluid replacement, and medications to manage symptoms. In some cases, treatment may also involve the use of antidotes to neutralize the effects of paraquat in the body.
Thioredoxin reductase 1 (TrxR1) is an enzyme that plays a crucial role in the regulation of cellular redox homeostasis. It is a member of the thioredoxin reductase family of enzymes, which are involved in the reduction of thioredoxin, a small protein that acts as a reducing agent in various cellular processes. TrxR1 is primarily located in the mitochondria and is involved in the regulation of the electron transport chain, which is responsible for generating ATP, the cell's primary energy source. It also plays a role in the regulation of various cellular processes, including cell growth, differentiation, and apoptosis. In the medical field, TrxR1 has been implicated in a number of diseases, including cancer, neurodegenerative disorders, and cardiovascular disease. For example, TrxR1 has been shown to be overexpressed in many types of cancer, and its inhibition has been proposed as a potential therapeutic strategy for the treatment of these diseases. Additionally, TrxR1 has been shown to play a role in the development of neurodegenerative disorders such as Alzheimer's disease and Parkinson's disease, and its inhibition has been proposed as a potential therapeutic strategy for the treatment of these conditions.
Bacteria are single-celled microorganisms that are found in almost every environment on Earth, including soil, water, and the human body. In the medical field, bacteria are often studied and classified based on their characteristics, such as their shape, size, and genetic makeup. Bacteria can be either beneficial or harmful to humans. Some bacteria are essential for human health, such as the bacteria that live in the gut and help digest food. However, other bacteria can cause infections and diseases, such as strep throat, pneumonia, and meningitis. In the medical field, bacteria are often identified and treated using a variety of methods, including culturing and identifying bacteria using specialized laboratory techniques, administering antibiotics to kill harmful bacteria, and using vaccines to prevent bacterial infections.
Carbon monoxide (CO) is a colorless, odorless, and tasteless gas that is produced when fossil fuels such as coal, oil, and gas are burned incompletely. In the medical field, carbon monoxide poisoning is a serious condition that occurs when a person inhales high levels of the gas, which can interfere with the body's ability to transport oxygen to the tissues. Carbon monoxide binds to hemoglobin in red blood cells, forming carboxyhemoglobin, which reduces the amount of oxygen that can be carried by the blood. This can lead to symptoms such as headache, dizziness, nausea, confusion, and shortness of breath. In severe cases, carbon monoxide poisoning can cause unconsciousness, seizures, and even death. The medical treatment for carbon monoxide poisoning involves removing the person from the source of the gas and providing oxygen therapy to help restore normal oxygen levels in the blood. In some cases, additional medical treatment may be necessary to manage symptoms and prevent complications.
Dianisidine is a chemical compound that is used as a stain in histology to visualize certain types of cells and structures in tissue samples. It is a basic dye that stains acidic structures, such as lysosomes and nuclei, in a bright red color. Dianisidine is commonly used to stain mast cells, which are immune cells that play a role in allergic reactions and inflammation. It is also used to stain other types of cells, such as eosinophils and basophils, which are also involved in immune responses. In addition to its use in histology, dianisidine is also used as a dye in other fields, such as textile manufacturing and as a colorant in cosmetics.
I'm sorry, but "Chromatiaceae" is not a term commonly used in the medical field. It is actually a taxonomic family of bacteria that belongs to the phylum Proteobacteria. In the medical field, bacteria are often studied for their potential to cause disease or to be used in the development of new treatments. Some members of the Chromatiaceae family are known to produce pigments and other compounds that have potential applications in biotechnology and medicine. However, the family as a whole is not typically associated with human health or disease.
In the medical field, nitrogen oxides (NOx) are a group of gases that are formed when nitrogen and oxygen react at high temperatures. These gases are commonly found in the atmosphere and are also produced by various human activities, such as burning fossil fuels and industrial processes. NOx gases can have harmful effects on human health, particularly on the respiratory system. When inhaled, they can cause irritation of the airways, coughing, wheezing, and shortness of breath. Long-term exposure to high levels of NOx can lead to chronic respiratory diseases, such as asthma and chronic obstructive pulmonary disease (COPD). In addition to their respiratory effects, NOx gases can also contribute to the formation of ground-level ozone, which is a major component of smog and can cause eye irritation, coughing, and other respiratory symptoms. NOx gases can also contribute to the formation of fine particulate matter, which can be inhaled deep into the lungs and cause a range of health problems, including heart disease, stroke, and lung cancer. Overall, the medical community recognizes the importance of monitoring and controlling NOx emissions to protect public health and reduce the risk of respiratory and other health problems associated with exposure to these gases.
Viologens are a class of organic compounds that contain a vinylene group (-CH=CH-) attached to a nitrogen atom. They are often used as electron donors in redox reactions and as dyes in various applications, including in the medical field. In medicine, viologens have been used as photosensitizers in photodynamic therapy (PDT) for the treatment of various types of cancer. PDT involves the administration of a photosensitizer, followed by exposure to a specific wavelength of light, which triggers the release of reactive oxygen species that can damage cancer cells. Viologens have also been used as electron donors in redox reactions in the development of new drugs and as dyes in diagnostic imaging. Overall, viologens have a wide range of potential applications in the medical field, and ongoing research is exploring their use in new and innovative ways.
Crystallography, X-ray is a technique used in the medical field to study the structure of biological molecules, such as proteins and nucleic acids, by analyzing the diffraction patterns produced by X-rays passing through the sample. This technique is used to determine the three-dimensional structure of these molecules, which is important for understanding their function and for developing new drugs and therapies. X-ray crystallography is a powerful tool that has been instrumental in advancing our understanding of many important biological processes and diseases.
Hemoglobins are a group of proteins found in red blood cells (erythrocytes) that are responsible for carrying oxygen from the lungs to the body's tissues and carbon dioxide from the tissues back to the lungs. Hemoglobin is composed of four subunits, each of which contains a heme group that binds to oxygen. The oxygen binds to the iron atom in the heme group, allowing the hemoglobin to transport oxygen throughout the body. Hemoglobin also plays a role in regulating the pH of the blood and in the immune response. Abnormalities in hemoglobin can lead to various medical conditions, such as anemia, sickle cell disease, and thalassemia.
In the medical field, Tungsten compounds are chemical compounds that contain the element tungsten. Tungsten is a heavy metal that is known for its high melting point and strength, and it is used in a variety of medical applications. One common use of tungsten compounds in medicine is in the production of medical devices, such as surgical instruments and prosthetic devices. Tungsten is often used in these devices because of its high strength and durability, which allows it to withstand the rigors of medical use. Tungsten compounds are also used in the treatment of certain medical conditions. For example, tungsten-based radioactive isotopes are used in radiation therapy to treat cancer. These isotopes emit radiation that can damage cancer cells, while leaving healthy cells relatively unharmed. In addition, tungsten compounds are used in the production of certain medical imaging technologies, such as X-ray machines and computed tomography (CT) scanners. Tungsten is used in these devices because of its high density, which allows it to absorb X-rays and produce clear, detailed images of the inside of the body. Overall, tungsten compounds play an important role in the medical field, and they are used in a variety of medical applications to improve patient care and treatment outcomes.
Nitrite reductase (NO-forming)
Nitrite reductase (disambiguation)
Cytochrome c nitrite reductase
Nitrite reductase (NAD(P)H)
Nitrate reductase (disambiguation)
Hydroxylamine reductase (NADH)
Transition metal nitrate complex
Nitrate reductase test
S. Samar Hasnain
Jessica A. Scoffield
Nitrite reductase (NO-forming) - Wikipedia
Structural dynamics of nitrite reductase | | Project | Fact sheet | FP4 | CORDIS | European Commission
Cardiac contractility in Antarctic teleost is modulated by nitrite through xanthine oxidase and cytochrome p-450 nitrite...
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- In enzymology, a nitrite reductase (NO-forming) (EC 18.104.22.168) is an enzyme that catalyzes the chemical reaction nitric oxide + H2O + ferricytochrome c ⇌ nitrite + ferrocytochrome c + 2 H+ The 3 substrates of this enzyme are nitric oxide, H2O, and ferricytochrome c, whereas its 3 products are nitrite, ferrocytochrome c, and H+. (wikipedia.org)
- In mammalian and non-mammalian vertebrates, nitrite anion, the largest pool of intravascular and tissue nitric oxide storage, represents a key player of many biological processes, including cardiac modulation. (unical.it)
- Since haemoglobin is crucial in nitric oxide homeostasis, the icefish, a naturally occurring genetic knockout for this protein, provides exclusive opportunities to investigate nitric oxide/nitrite signaling. (unical.it)
- In vivo, nitrite conversion to nitric oxide requires the nitrite reductase activity of xanthine oxidase and cytochrome P-450, thus the involvement of these enzymes was also evaluated. (unical.it)
- We showed that, in C. hamatus and T. bernacchii, nitrite influenced cardiac performance by inducing a concentration-dependent positive inotropic effect which was unaffected by nitric oxide scavenging by PTIO in C. hamatus, while it was abolished in T. bernacchii. (unical.it)
- Results suggested that in the heart of C. hamatus and T. bernacchii, nitrite is an integral physiological source of nitric oxide with important signaling properties, which require the nitrite reductase activity of xanthine oxidase and cytochrome P-450. (unical.it)
- 2001. Effects of pH, nitrite, and ascorbic acid on nonenzymatic nitric oxide generation and bacterial growth in urine. (cdc.gov)
Nitrate to nitrite2
Cytochrome b5 reduct2
- It occurs when there is a problem with an enzyme called cytochrome b5 reductase . (medlineplus.gov)
- The pathway responsible for reducing most methemoglobin (95%-99%) back to hemoglobin is the NADH-dependant methemoglobin reductase system, in which the enzyme cytochrome-b5 reductase plays a crucial role in a transfer of electrons from NADH to methemoglobin. (medscape.com)
- In the mechanism of reduction of nitrite (N02-) to nitrous oxide (NO), both the substrate binding reaction and the electron transfer can be observed, and preliminary X-ray experiments using cryo-cooling diffraction indicate an important conformational control of the reaction and sufficiently long-lived intermediates to be caught by freesing. (europa.eu)
- In particular, the enzymes that will be discussed are Cyt P450cam, myoglobin, and human serum albumin complexed with heme, and their function in reacting with NOx species (e.g. nitrite reduction) or oxidizing sulfur-containing compounds (e.g. oxidative desulfurization). (ju.edu)
- For information on how to detect nitrate and nitrite reductase activity, refer to the nitrate reduction test . (vumicro.com)
- T1CuN and T2Cu are connected by a typical Cys-His bridge and an unexpected sensing loop which harbours a SerCAT residue close to T2Cu, suggesting an alternative nitrite-reduction mechanism in these enzymes. (diamond.ac.uk)
- 1981. Accidental poisoning of two laboratory technologists with sodium nitrite. (cdc.gov)
- In addition, specific antidotes are methylene blue for methemoglobinemia and thiosulfate/sodium nitrite for cyanide (CN) poisoning. (medscape.com)
- Amyl nitrite and sodium nitrite convert a portion of circulating hemoglobin to methemoglobin. (medscape.com)
- Specific inhibition of xanthine oxidase and cytochrome P-450 revealed, in the two teleosts, that the nitrite-dependent inotropism required the nitrite reductase activity of both enzymes. (unical.it)
- Dissimilatory nitrite reductases are key enzymes in the denitrification pathway, reducing nitrite and leading to the production of gaseous products (NO, N2O and N2). (diamond.ac.uk)
- The reaction is catalysed either by a Cu-containing nitrite reductase (NirK) or by a cytochrome cd1 nitrite reductase (NirS), as the simultaneous presence of the two enzymes has never been detected in the same microorganism. (diamond.ac.uk)
- Sodium tungstate was used in this study to implement nitrogen stress by inhibiting nitrate reductase (NR) in Dunaliella tertiolecta . (hindawi.com)
- Some also have an enzyme called nitrite reductase that can convert nitrite into nitrogen gas. (vumicro.com)
- If the bacterium also produces nitrite reductase, nitrogen gas will be liberated. (vumicro.com)
- Alternative pathways by which methemoglobin can be reduced, which become more important in deficiencies of the primary pathway, involve the NADPH-methemoglobin reductase system, reducing agents such as ascorbic acid, and reduced glutathione. (medscape.com)
- 2004. Dietary nitrites and nitrates, nitrosatable drugs, and neural tube defects. (cdc.gov)
- 1994. Fatal methemoglobinemia due to inhalation of isobutyl nitrite. (cdc.gov)
- Therapeutic uses of inorganic nitrite and nitrate: from the past to the future. (cdc.gov)
- Molecular characterization of a copper-containing nitrite reductase from Rhodopseudomonas sphaeriodes forma sp. (wikipedia.org)
- 1993. The effects of nitrate, nitrite and N-nitroso compounds on human health: a review. (cdc.gov)
- Disease activity and impairment were determined and artificial suction blisters were made on the CRPS1 and the contralateral extremities for measurements of IL-6, TNF-α, ET-1 and nitrate/nitrite (NOx). (biomedcentral.com)
- This robust N2O-reducing activity of B. ottawaense was confirmed by N2O reductase (NosZ) protein levels and by mitigation of N2O emitted by nodule decomposition in laboratory system. (bvsalud.org)
- We characterized GbsMerA, a mercury reductase belonging to the mercury-resistant operon of Gelidibacter salicanalis PAMC21136, and found its maximum activity of 474.7 µmol/min/mg in reducing Hg+2. (bvsalud.org)
- Other names in common use include cd-cytochrome nitrite reductase, [nitrite reductase (cytochrome)] [misleading, see comments. (wikipedia.org)
- To achieve this goal we propose to undertake a comprehensive and detailed study of a series of related Nitrite Reductases (NiR). (europa.eu)
- This study analysed the influence elicited by nitrite on the performance of the perfused beating heart of two Antarctic stenotherm teleosts, the haemoglobinless Chionodraco hamatus (icefish) and the red-blooded Trematomus bernacchii. (unical.it)
- Results from this work provide a foundation for designing enhanced catalysts based on the nitrite reductase or desulfurase activities of porphyrin proteins. (ju.edu)
- This medium is used to determine whether the microbe has the enzyme nitrate reductase. (vumicro.com)
- As shown by our studies on Antarctic teleosts, nitrite-dependent cardiac regulation is of great relevance also in cold-blooded vertebrates. (unical.it)
- Other names in common use include cd-cytochrome nitrite reductase, [nitrite reductase (cytochrome)] [misleading, see comments. (wikipedia.org)
- 2. Nanomaterial-based electrochemical biosensors for cytochrome c using cytochrome c reductase. (nih.gov)
- 3. ARM-microcontroller based portable nitrite electrochemical analyzer using cytochrome c reductase biofunctionalized onto screen printed carbon electrode. (nih.gov)
- 19. A nitrite biosensor based on the immobilization of cytochrome c on multi-walled carbon nanotubes-PAMAM-chitosan nanocomposite modified glass carbon electrode. (nih.gov)
- nitrite reductase (cytochrome)] [misleading, see comments. (qmul.ac.uk)
- Cytochrome cd 1 also has oxidase and hydroxylamine reductase activities. (qmul.ac.uk)
- May also catalyse the reaction of hydroxylamine reductase ( EC 22.214.171.124 ) since this is a well-known activity of cytochrome cd 1 . (qmul.ac.uk)
- In enzymology, a nitrite reductase (NO-forming) (EC 126.96.36.199) is an enzyme that catalyzes the chemical reaction nitric oxide + H2O + ferricytochrome c ⇌ nitrite + ferrocytochrome c + 2 H+ The 3 substrates of this enzyme are nitric oxide, H2O, and ferricytochrome c, whereas its 3 products are nitrite, ferrocytochrome c, and H+. (wikipedia.org)
- 2001. Effects of pH, nitrite, and ascorbic acid on nonenzymatic nitric oxide generation and bacterial growth in urine. (cdc.gov)
- Copper nitrite reductases (CuNiRs) catalyze the reduction of nitrite to form nitric oxide. (ebsco.com)
- Collectively, these findings suggest hypoxia, and to a far greater extent exercise, independently promote arteriovenous delivery gradients of intravascular nitric oxide with deoxyhemoglobin mediated nitrite reduction, identified as the dominant mechanism underlying hypoxic vasodilation. (libsyn.com)
- These studies reveal that nitrite is a potent vasodilator in humans, is bioactivated by reaction with deoxyhemoglobin to generate NO preferentially under hypoxic conditions and suggest that hemoglobin has an enzymatic property of a nitrite reductase that participates in hypoxic vasodilation. (nih.gov)
- The discovery of a novel physiological function for hemoglobin as an electronically and allosterically regulated nitrite reductase (Cosby, et al. (nih.gov)
- Hemolysis and Heinz body formation may be exaggerated in individuals with a glucose-6-phosphate dehydrogenase (G6PD) deficiency, or methemoglobin reductase deficiency, or hemoglobin M. This reaction is frequently dose-related. (nih.gov)
- Plasma nitrite gradients reflecting consumption were accompanied by red blood cell iron nitrosyl hemoglobin formation at rest in normoxia, during hypoxia and especially during exercise, with the most pronounced gradients observed across the femoral circulation. (libsyn.com)
- Drugs or chemicals which have produced significant hemolysis in G6PD or methemoglobin reductase deficient patients include Dapsone, sulfanilamide, nitrite, aniline, phenylhydrazine, napthalene, niridazole, nitro-furantoin and 8-amino-antimalarials such as primaquine. (nih.gov)
- 11]. Nitrite was measured adding Griess reagent, 1 sulfanilamide, 0.1 N-1-naphthalenediamine and two.5 phosphoric acid. (adenosine-receptor.com)
- The present study evaluates sequence conservation in the gene coding for nitrite reductase (aniA) and AniA expression from a panel of Neisseria meningitidis isolates. (nih.gov)
- It catalyzes the six-electron oxidation of AMMONIA to nitrite. (bvsalud.org)
- Isolation of the tungsten analogue of nitrate reductase with B.A. Notton provided the rationale for current uses of tungsten and helped towards further understanding of 'whiptail. (studyres.com)
- Absorbance was measured at 535 nm and nitrite concentration in the cell supernatant was calculated from a regular curve of optica. (adenosine-receptor.com)
- Sampling saliva is simple, non-invasive and the concentration of nitrite in both plasma and saliva is an important biomarker for NO production/availability. (humann.com)
- Nitrite reacts with certain chemicals to yield a red-colored product. (vumicro.com)
- It consists of two domains and forms trimers and hence resembles the quaternary structure of nitrite reductases or ceruloplasmins more than that of large laccases. (nih.gov)
- 41 years, with a mean age of 27.0 (standard examination, nitrite reductase, leukocyte deviation 4.9) years. (who.int)
- Microscopic examina- tion had the highest sensitivity (67%), while nitrite dipstick testing showed the highest specificity and positive predictive value (99% and 57% respectively). (who.int)