Pyruvate oxidase is an enzyme complex located within the mitochondrial matrix that catalyzes the oxidative decarboxylation of pyruvate into acetyl-CoA, thereby linking glycolysis to the citric acid cycle and playing a crucial role in cellular energy production.
The coenzyme form of Vitamin B1 present in many animal tissues. It is a required intermediate in the PYRUVATE DEHYDROGENASE COMPLEX and the KETOGLUTARATE DEHYDROGENASE COMPLEX.
ATP:pyruvate 2-O-phosphotransferase. A phosphotransferase that catalyzes reversibly the phosphorylation of pyruvate to phosphoenolpyruvate in the presence of ATP. It has four isozymes (L, R, M1, and M2). Deficiency of the enzyme results in hemolytic anemia. EC 2.7.1.40.
A condensation product of riboflavin and adenosine diphosphate. The coenzyme of various aerobic dehydrogenases, e.g., D-amino acid oxidase and L-amino acid oxidase. (Lehninger, Principles of Biochemistry, 1982, p972)
A flavoprotein enzyme that catalyzes the formation of acetolactate from 2 moles of PYRUVATE in the biosynthesis of VALINE and the formation of acetohydroxybutyrate from pyruvate and alpha-ketobutyrate in the biosynthesis of ISOLEUCINE. This enzyme was formerly listed as EC 4.1.3.18.
A multienzyme complex responsible for the formation of ACETYL COENZYME A from pyruvate. The enzyme components are PYRUVATE DEHYDROGENASE (LIPOAMIDE); dihydrolipoamide acetyltransferase; and LIPOAMIDE DEHYDROGENASE. Pyruvate dehydrogenase complex is subject to three types of control: inhibited by acetyl-CoA and NADH; influenced by the energy state of the cell; and inhibited when a specific serine residue in the pyruvate decarboxylase is phosphorylated by ATP. PYRUVATE DEHYDROGENASE (LIPOAMIDE)-PHOSPHATASE catalyzes reactivation of the complex. (From Concise Encyclopedia Biochemistry and Molecular Biology, 3rd ed)
A flavoprotein enzyme that catalyzes the univalent reduction of OXYGEN using NADPH as an electron donor to create SUPEROXIDE ANION. The enzyme is dependent on a variety of CYTOCHROMES. Defects in the production of superoxide ions by enzymes such as NADPH oxidase result in GRANULOMATOUS DISEASE, CHRONIC.
A species of rod-shaped, LACTIC ACID bacteria used in PROBIOTICS and SILAGE production.
Life or metabolic reactions occurring in an environment containing oxygen.
A genus of gram-positive, microaerophilic, rod-shaped bacteria occurring widely in nature. Its species are also part of the many normal flora of the mouth, intestinal tract, and vagina of many mammals, including humans. Pathogenicity from this genus is rare.
A species of gram-negative, facultatively anaerobic, rod-shaped bacteria (GRAM-NEGATIVE FACULTATIVELY ANAEROBIC RODS) commonly found in the lower part of the intestine of warm-blooded animals. It is usually nonpathogenic, but some strains are known to produce DIARRHEA and pyogenic infections. Pathogenic strains (virotypes) are classified by their specific pathogenic mechanisms such as toxins (ENTEROTOXIGENIC ESCHERICHIA COLI), etc.
An intermediate compound in the metabolism of carbohydrates, proteins, and fats. In thiamine deficiency, its oxidation is retarded and it accumulates in the tissues, especially in nervous structures. (From Stedman, 26th ed)
Pyruvates, in the context of medical and biochemistry definitions, are molecules that result from the final step of glycolysis, containing a carboxylic acid group and an aldehyde group, playing a crucial role in cellular metabolism, including being converted into Acetyl-CoA to enter the Krebs cycle or lactate under anaerobic conditions.
Catalyzes the decarboxylation of an alpha keto acid to an aldehyde and carbon dioxide. Thiamine pyrophosphate is an essential cofactor. In lower organisms, which ferment glucose to ethanol and carbon dioxide, the enzyme irreversibly decarboxylates pyruvate to acetaldehyde. EC 4.1.1.1.
Derivatives of ACETIC ACID. Included under this heading are a broad variety of acid forms, salts, esters, and amides that contain the carboxymethane structure.
Works containing information articles on subjects in every field of knowledge, usually arranged in alphabetical order, or a similar work limited to a special field or subject. (From The ALA Glossary of Library and Information Science, 1983)

Interplay of organic and biological chemistry in understanding coenzyme mechanisms: example of thiamin diphosphate-dependent decarboxylations of 2-oxo acids. (1/79)

With the publication of the three-dimensional structures of several thiamin diphosphate-dependent enzymes, the chemical mechanism of their non-oxidative and oxidative decarboxylation reactions is better understood. Chemical models for these reactions serve a useful purpose to help evaluate the additional catalytic rate acceleration provided by the protein component. The ability to generate, and spectroscopically observe, the two key zwitterionic intermediates invoked in such reactions allowed progress to be made in elucidating the rates and mechanisms of the elementary steps leading to and from these intermediates. The need remains to develop chemical models, which accurately reflect the enzyme-bound conformation of this coenzyme.  (+info)

Crystal versus solution structures of thiamine diphosphate-dependent enzymes. (2/79)

The quaternary structures of the thiamine diphosphate-dependent enzymes transketolase (EC 2.2.1.1; from Saccharomyces cerevisiae), pyruvate oxidase (EC 1.2.3.3; from Lactobacillus plantarum), and pyruvate decarboxylase (EC 4.1.1.1; from Zymomonas mobilis and brewers' yeast, the latter in the native and pyruvamide-activated forms) were examined by synchrotron x-ray solution scattering. The experimental scattering data were compared with the curves calculated from the crystallographic models of these multisubunit enzymes. For all enzymes noted above, except the very compact pyruvate decarboxylase from Z. mobilis, there were significant differences between the experimental and calculated profiles. The changes in relative positions of the subunits in solution were determined by rigid body refinement. For pyruvate oxidase and transketolase, which have tight intersubunit contacts in the crystal, relatively small modifications of the quaternary structure (root mean square displacements of 0.23 and 0.27 nm, respectively) sufficed to fit the experimental data. For the enzymes with looser contacts (the native and activated forms of yeast pyruvate decarboxylase), large modifications of the crystallographic models (root mean square displacements of 0.58 and 1.53 nm, respectively) were required. A clear correlation was observed between the magnitude of the distortions induced by the crystal environment and the interfacial area between subunits.  (+info)

Inhibitory and bactericidal effects of hydrogen peroxide production by Streptococcus pneumoniae on other inhabitants of the upper respiratory tract. (3/79)

An inverse correlation between colonization of the human nasopharynx by Streptococcus pneumoniae and Haemophilus influenzae, both common upper respiratory pathogens, has been reported. Studies were undertaken to determine if either of these organisms produces substances which inhibit growth of the other. Culture supernatants from S. pneumoniae inhibited growth of H. influenzae, whereas culture supernatants from H. influenzae had no effect on the growth of S. pneumoniae. Moreover, coculture of S. pneumoniae and H. influenzae led to a rapid decrease in viable counts of H. influenzae. The addition of purified catalase prevented killing of H. influenzae in coculture experiments, suggesting that hydrogen peroxide may be responsible for this bactericidal activity. H. influenzae was killed by concentrations of hydrogen peroxide similar to that produced by S. pneumoniae. Hydrogen peroxide is produced by the pneumococcus through the action of pyruvate oxidase (SpxB) under conditions of aerobic growth. Both an spxB mutant and a naturally occurring variant of S. pneumoniae, which is downregulated in SpxB expression, were unable to kill H. influenzae. A catalase-reversible inhibitory effect of S. pneumoniae on the growth of the respiratory tract pathogens Moraxella catarrhalis and Neisseria meningitidis was also observed. Elevated hydrogen peroxide production, therefore, may be a means by which S. pneumoniae is able to inhibit a variety of competing organisms in the aerobic environment of the upper respiratory tract.  (+info)

Differential protein expression in phenotypic variants of Streptococcus pneumoniae. (4/79)

Streptococcus pneumoniae undergoes spontaneous phase variation resulting in opaque and transparent colony forms. Differences in colony opacity correlate with differences in virulence: the transparent variants are more capable of colonizing the nasopharynx, whereas the opaque variants show increased virulence during systemic infections. To gain insight into the pathogenesis of pneumococcal disease at the molecular level, protein expression patterns of the phenotypic variants of two pneumococcal strains were compared by high-resolution two-dimensional protein electrophoresis. In comparison with transparent variants, the opaque variants reduced the expression of two proteins and overexpressed one protein. The proteins were identified by mass spectrometric analysis. The protein overexpressed in the opaque phenotype revealed significant homology to elongation factor Ts of Helicobacter pylori. One of the two proteins that were underexpressed in the opaque variants revealed significant homology to the proteinase maturation protein PrtM of Lactocobacillus paracasei, a member of the family of peptidyl-prolyl cis/trans isomerases. A consensus lipoprotein signal sequence suggests that the putative proteinase maturation protein A, designated PpmA, is located at the surface of the pneumococcus and may play a role in the maturation of surface or secreted proteins. The second underexpressed protein was identified as pyruvate oxidase, SpxB. The lower SpxB expression in opaque variants most probably explains the reduced production of hydrogen peroxide, a reaction product of SpxB, in this variant. Since a spxB-defective pneumococcal mutant has decreased ability to colonize the nasopharynx (B. Spellerberg, D. R. Cundell, J. Sandros, B. J. Pearce, I. Idanpaan-Heikkila, C. Rosenow, and H. R. Masure, 1996. Mol. Microbiol. 19:803-813, 1996), our data suggest that SpxB plays an important role in enhancing the ability of transparent variants to efficiently colonize the nasopharynx.  (+info)

Reactivation of the lipid-depleted pyruvate oxidase system from Escherichia coli with cell envelope neutral lipids. (5/79)

The pyruvate oxidase system of Escherichia coli is composed of a soluble flavoprotein, pyruvate oxidase (EC 1.2.2.2, pyruvate:ferricytochrome b1 oxidoreductase), and an electron transport system associated with the cell envelope-membrane fraction. The membrane particles contain 15% lipid by weight. Fractionation of the lipids revealed that abut one-third are neutral lipids and two-thirds are phospholipids. The relative ratio of ubiquinone to menaquinone within the neutral lipid fraction is 15:1 on a molar basis. Removal of the lipids from the membrane particles by extraction with aqueous acetone or hydrolysis of the phospholipids by treatment with Bacillus cereus phospholipase C results in a complete loss of electron transport activity. Analysis of the particles extracted with aqueous acetone revealed that practically all the neutral lipids and 65% of the phospholipids are removed by this treatment. Phospholipase treatment results in a loss of 75% of the membrane phospholipid phosphorus; however, the diglycerides and the neutral lipids produced by phospholipase hydrolysis remain associated with the particles. Addition of neutral lipid and a detergent, hepta-DL-alanyl dodecylamide to the acetone-extracted material results in a restoration of 37% of the original particle activity. Addition of neutral lipid and hepta-DL-alanyl dodecylamide to phospholipase-treated particles completely restores the original electron transport activity. Furthermore, addition of ubiquinone from either yeast (UQ6) or E. coli (UQ8) will restore pyruvate oxidase activity when the quinones are supplemented with photoinactivated neutral lipid. No restoration of activity to phospholipase-treated particles is noted upon the addition of either menaquinone 6 or menaquinone 8 to the reconstitution system. In fact, these compounds appear to suppress restoration of activity when they are added to reaction mixtures containing neutral lipid and phospholipase-treated particles.  (+info)

Conversion of Escherichia coli pyruvate oxidase to an 'alpha-ketobutyrate oxidase'. (6/79)

Escherichia coli pyruvate oxidase (PoxB), a lipid-activated homotetrameric enzyme, is active on both pyruvate and 2-oxobutanoate ('alpha-ketobutyrate'), although pyruvate is the favoured substrate. By localized random mutagenesis of residues chosen on the basis of a modelled active site, we obtained several PoxB enzymes that had a markedly decreased activity with the natural substrate, pyruvate, but retained full activity with 2-oxobutanoate. In each of these mutant proteins Val-380 had been replaced with a smaller residue, namely alanine, glycine or serine. One of these, PoxB V380A/L253F, was shown to lack detectable pyruvate oxidase activity in vivo; this protein was purified, studied and found to have a 6-fold increase in K(m) for pyruvate and a 10-fold lower V(max) with this substrate. In contrast, the mutant had essentially normal kinetic constants with 2-oxobutanoate. The altered substrate specificity was reflected in a decreased rate of pyruvate binding to the latent conformer of the mutant protein owing to the V380A mutation. The L253F mutation alone had no effect on PoxB activity, although it increased the activity of proteins carrying substitutions at residue 380, as it did that of the wild-type protein. The properties of the V380A/L253F protein provide new insights into the mode of substrate binding and the unusual activation properties of this enzyme.  (+info)

Competence regulation by oxygen availability and by Nox is not related to specific adjustment of central metabolism in Streptococcus pneumoniae. (7/79)

In Streptococcus pneumoniae oxygen availability is a major determinant for competence development in exponentially growing cultures. NADH oxidase activity is required for optimal competence in cultures grown aerobically. The implication of oxidative metabolism and more specifically of Nox on central metabolism has been examined. Glycolytic flux throughout exponential growth revealed homolactic fermentation with a lactate production/glucose utilization ratio close to 2, whatever the aerobiosis level of the culture. Loss-of-function mutations in nox, which encodes NADH oxidase, did not change this trait. Consistently, mRNA levels of glyceraldehyde-3-phosphate dehydrogenase, L-lactate dehydrogenase, pyruvate oxidase, and NADH oxidase remained comparable to wild-type levels, as did the specific activities of key enzymes which control central metabolism. Competence regulation by oxygen involving the NADH oxidase activity is not due to significant modification of carbon flux through glycolysis. Failure to obtain loss-of-function mutation in L-ldh, which encodes the L-lactate dehydrogenase, indicates its essential role in pneumococci whatever their growth status.  (+info)

Pyruvate oxidase contributes to the aerobic growth efficiency of Escherichia coli. (8/79)

The metabolic importance of pyruvate oxidase (PoxB), which converts pyruvate directly to acetate and CO(2), was assessed using an isogenic set of genetically engineered strains of Escherichia coli. In a strain lacking the pyruvate dehydrogenase complex (PDHC), PoxB supported acetate-independent aerobic growth when the poxB gene was expressed constitutively or from the IPTG-inducible tac promoter. Using aerobic glucose-limited chemostat cultures of PDH-null strains, it was found that steady-states could be maintained at a low dilution rate (0.05 h(-1)) when PoxB is expressed from its natural promoter, but not at higher dilution rates (up to at least 0.25 h(-1)) unless expressed constitutively or from the tac promoter. The poor complementation of PDH-deficient strains by poxB plasmids was attributed to several factors including the stationary-phase-dependent regulation of the natural poxB promoter and deleterious effects of the multicopy plasmids. As a consequence of replacing the PDH complex by PoxB, the growth rate (mu(max)), growth yield (Y(max)) and the carbon conversion efficiency (flux to biomass) were lowered by 33%, 9-25% and 29-39% (respectively), indicating that more carbon has to be oxidized to CO(2) for energy generation. Extra energy is needed to convert PoxB-derived acetate to acetyl-CoA for further metabolism and enzyme analysis indicated that acetyl-CoA synthetase is induced for this purpose. In similar experiments with a PoxB-null strain it was shown that PoxB normally makes a significant contribution to the aerobic growth efficiency of E. coli. In glucose minimal medium, the respective growth rates (mu(max)), growth yields (Y(max)) and carbon conversion efficiencies were 16%, 14% and 24% lower than the parental values, and correspondingly more carbon was fluxed to CO(2) for energy generation. It was concluded that PoxB is used preferentially at low growth rates and that E. coli benefits from being able to convert pyruvate to acetyl-CoA by a seemingly wasteful route via acetate.  (+info)

Pyruvate oxidase is not a term that has a widely recognized medical definition. However, pyruvate oxidase is an enzyme that plays a role in the metabolism of glucose in cells. It is involved in the conversion of pyruvate, a product of glycolysis, into acetyl-CoA, which can then be used in the citric acid cycle (also known as the Krebs cycle) to generate energy in the form of ATP.

Pyruvate oxidase is found in the mitochondria of cells and requires molecular oxygen (O2) to function. It catalyzes the following reaction:

pyruvate + CoA + NAD+ + H2O → acetyl-CoA + CO2 + NADH + H+

Deficiencies in pyruvate oxidase have been associated with certain metabolic disorders, such as pyruvate dehydrogenase deficiency and Leigh syndrome. However, these conditions are typically caused by defects in other enzymes involved in the metabolism of pyruvate rather than pyruvate oxidase itself.

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

Pyruvate kinase is an enzyme that plays a crucial role in the final step of glycolysis, a process by which glucose is broken down to produce energy in the form of ATP (adenosine triphosphate). Specifically, pyruvate kinase catalyzes the transfer of a phosphate group from phosphoenolpyruvate (PEP) to adenosine diphosphate (ADP), resulting in the formation of pyruvate and ATP.

There are several isoforms of pyruvate kinase found in different tissues, including the liver, muscle, and brain. The type found in red blood cells is known as PK-RBC or PK-M2. Deficiencies in pyruvate kinase can lead to a genetic disorder called pyruvate kinase deficiency, which can result in hemolytic anemia due to the premature destruction of red blood cells.

Flavin-Adenine Dinucleotide (FAD) is a coenzyme that plays a crucial role in various metabolic processes, particularly in the electron transport chain where it functions as an electron carrier in oxidation-reduction reactions. FAD is composed of a flavin moiety, riboflavin or vitamin B2, and adenine dinucleotide. It can exist in two forms: an oxidized form (FAD) and a reduced form (FADH2). The reduction of FAD to FADH2 involves the gain of two electrons and two protons, which is accompanied by a significant conformational change that allows FADH2 to donate its electrons to subsequent components in the electron transport chain, ultimately leading to the production of ATP, the main energy currency of the cell.

Acetolactate synthase (ALS), also known as acetohydroxyacid synthase (AHAS), is a key enzyme in the biosynthetic pathway of branched-chain amino acids (valine, leucine, and isoleucine) in bacteria, fungi, and plants. It catalyzes the first step in the pathway, which is the condensation of two molecules of pyruvate to form acetolactate.

Inhibitors of ALS, such as sulfonylureas and imidazolinones, are widely used as herbicides because they disrupt the biosynthesis of amino acids that are essential for plant growth and development. These inhibitors work by binding to the active site of the enzyme and preventing the substrate from accessing it.

In humans, ALS is not involved in the biosynthesis of branched-chain amino acids, but a homologous enzyme called dihydroorotate dehydrogenase (DHOD) plays a crucial role in the synthesis of pyrimidine nucleotides. Inhibitors of DHOD are used as immunosuppressants to treat autoimmune diseases, such as rheumatoid arthritis and multiple sclerosis.

The Pyruvate Dehydrogenase Complex (PDC) is a multi-enzyme complex that plays a crucial role in cellular energy metabolism. It is located in the mitochondrial matrix and catalyzes the oxidative decarboxylation of pyruvate, the end product of glycolysis, into acetyl-CoA. This reaction links the carbohydrate metabolism (glycolysis) to the citric acid cycle (Krebs cycle), enabling the continuation of energy production in the form of ATP through oxidative phosphorylation.

The Pyruvate Dehydrogenase Complex consists of three main enzymes: pyruvate dehydrogenase (E1), dihydrolipoyl transacetylase (E2), and dihydrolipoyl dehydrogenase (E3). Additionally, two regulatory enzymes are associated with the complex: pyruvate dehydrogenase kinase (PDK) and pyruvate dehydrogenase phosphatase (PDP). These regulatory enzymes control the activity of the PDC through reversible phosphorylation and dephosphorylation, allowing the cell to adapt to varying energy demands and substrate availability.

Deficiencies or dysfunctions in the Pyruvate Dehydrogenase Complex can lead to various metabolic disorders, such as pyruvate dehydrogenase deficiency, which may result in neurological impairments and lactic acidosis due to disrupted energy metabolism.

NADPH oxidase is an enzyme complex that plays a crucial role in the production of reactive oxygen species (ROS) in various cell types. The primary function of NADPH oxidase is to catalyze the transfer of electrons from NADPH to molecular oxygen, resulting in the formation of superoxide radicals. This enzyme complex consists of several subunits, including two membrane-bound components (gp91phox and p22phox) and several cytosolic components (p47phox, p67phox, p40phox, and rac1 or rac2). Upon activation, these subunits assemble to form a functional enzyme complex that generates ROS, which serve as important signaling molecules in various cellular processes. However, excessive or uncontrolled production of ROS by NADPH oxidase has been implicated in the pathogenesis of several diseases, such as cardiovascular disorders, neurodegenerative diseases, and cancer.

Lactobacillus plantarum is a species of gram-positive, rod-shaped bacteria that belongs to the lactic acid bacteria group. It is a facultative anaerobe, meaning it can grow in the presence or absence of oxygen. Lactobacillus plantarum is commonly found in a variety of environments, including fermented foods such as sauerkraut, kimchi, and sourdough bread, as well as in the gastrointestinal tract of humans and other animals.

Lactobacillus plantarum is known for its ability to produce lactic acid through the fermentation of carbohydrates, which can help to preserve food and inhibit the growth of harmful bacteria. It also produces various antimicrobial compounds that can help to protect against pathogens in the gut.

In addition to its use in food preservation and fermentation, Lactobacillus plantarum has been studied for its potential probiotic benefits. Probiotics are live bacteria and yeasts that are believed to provide health benefits when consumed, including improving digestive health, enhancing the immune system, and reducing the risk of certain diseases.

Research has suggested that Lactobacillus plantarum may have a range of potential health benefits, including:

* Improving gut barrier function and reducing inflammation in the gut
* Enhancing the immune system and reducing the risk of infections
* Alleviating symptoms of irritable bowel syndrome (IBS) and other gastrointestinal disorders
* Reducing the risk of allergies and asthma
* Improving oral health by reducing plaque and preventing tooth decay

However, more research is needed to fully understand the potential health benefits of Lactobacillus plantarum and to determine its safety and effectiveness as a probiotic supplement.

Aerobiosis is the process of living, growing, and functioning in the presence of oxygen. It refers to the metabolic processes that require oxygen to break down nutrients and produce energy in cells. This is in contrast to anaerobiosis, which is the ability to live and grow in the absence of oxygen.

In medical terms, aerobiosis is often used to describe the growth of microorganisms, such as bacteria and fungi, that require oxygen to survive and multiply. These organisms are called aerobic organisms, and they play an important role in many biological processes, including decomposition and waste breakdown.

However, some microorganisms are unable to grow in the presence of oxygen and are instead restricted to environments where oxygen is absent or limited. These organisms are called anaerobic organisms, and their growth and metabolism are referred to as anaerobiosis.

Lactobacillus is a genus of gram-positive, rod-shaped, facultatively anaerobic or microaerophilic, non-spore-forming bacteria. They are part of the normal flora found in the intestinal, urinary, and genital tracts of humans and other animals. Lactobacilli are also commonly found in some fermented foods, such as yogurt, sauerkraut, and sourdough bread.

Lactobacilli are known for their ability to produce lactic acid through the fermentation of sugars, which contributes to their role in maintaining a healthy microbiota and lowering the pH in various environments. Some species of Lactobacillus have been shown to provide health benefits, such as improving digestion, enhancing immune function, and preventing infections, particularly in the urogenital and intestinal tracts. They are often used as probiotics, either in food or supplement form, to promote a balanced microbiome and support overall health.

'Escherichia coli' (E. coli) is a type of gram-negative, facultatively anaerobic, rod-shaped bacterium that commonly inhabits the intestinal tract of humans and warm-blooded animals. It is a member of the family Enterobacteriaceae and one of the most well-studied prokaryotic model organisms in molecular biology.

While most E. coli strains are harmless and even beneficial to their hosts, some serotypes can cause various forms of gastrointestinal and extraintestinal illnesses in humans and animals. These pathogenic strains possess virulence factors that enable them to colonize and damage host tissues, leading to diseases such as diarrhea, urinary tract infections, pneumonia, and sepsis.

E. coli is a versatile organism with remarkable genetic diversity, which allows it to adapt to various environmental niches. It can be found in water, soil, food, and various man-made environments, making it an essential indicator of fecal contamination and a common cause of foodborne illnesses. The study of E. coli has contributed significantly to our understanding of fundamental biological processes, including DNA replication, gene regulation, and protein synthesis.

Pyruvic acid, also known as 2-oxopropanoic acid, is a key metabolic intermediate in both anaerobic and aerobic respiration. It is a carboxylic acid with a ketone functional group, making it a β-ketoacid. In the cytosol, pyruvate is produced from glucose during glycolysis, where it serves as a crucial link between the anaerobic breakdown of glucose and the aerobic process of cellular respiration in the mitochondria.

During low oxygen availability or high energy demands, pyruvate can be converted into lactate through anaerobic glycolysis, allowing for the continued production of ATP (adenosine triphosphate) without oxygen. In the presence of adequate oxygen and functional mitochondria, pyruvate is transported into the mitochondrial matrix where it undergoes oxidative decarboxylation to form acetyl-CoA by the enzyme pyruvate dehydrogenase complex (PDC). This reaction also involves the reduction of NAD+ to NADH and the release of CO2. Acetyl-CoA then enters the citric acid cycle, where it is further oxidized to produce energy in the form of ATP, NADH, FADH2, and GTP (guanosine triphosphate) through a series of enzymatic reactions.

In summary, pyruvic acid is a vital metabolic intermediate that plays a significant role in energy production pathways, connecting glycolysis to both anaerobic and aerobic respiration.

Pyruvate is a negatively charged ion or group of atoms, called anion, with the chemical formula C3H3O3-. It is formed from the decomposition of glucose and other sugars in the process of cellular respiration. Pyruvate plays a crucial role in the metabolic pathways that generate energy for cells.

In the cytoplasm, pyruvate is produced through glycolysis, where one molecule of glucose is broken down into two molecules of pyruvate, releasing energy and producing ATP (adenosine triphosphate) and NADH (reduced nicotinamide adenine dinucleotide).

In the mitochondria, pyruvate can be further metabolized through the citric acid cycle (also known as the Krebs cycle) to produce more ATP. The process involves the conversion of pyruvate into acetyl-CoA, which then enters the citric acid cycle and undergoes a series of reactions that generate energy in the form of ATP, NADH, and FADH2 (reduced flavin adenine dinucleotide).

Overall, pyruvate is an important intermediate in cellular respiration and plays a central role in the production of energy for cells.

Pyruvate decarboxylase is an enzyme that plays a crucial role in the cellular process of fermentation and gluconeogenesis. In medical and biochemical terms, pyruvate decarboxylase is defined as:

"An enzyme (EC 4.1.1.1) that catalyzes the decarboxylation of pyruvate to form acetaldehyde and carbon dioxide in the presence of thiamine pyrophosphate (TPP) as a cofactor. This reaction occurs during anaerobic metabolism, such as alcohol fermentation in yeast or bacteria, and helps to generate ATP and NADH for the cell's energy needs."

In humans, pyruvate decarboxylase is primarily found in the liver and kidneys, where it participates in gluconeogenesis – the process of generating new glucose molecules from non-carbohydrate precursors. The enzyme's activity is essential for maintaining blood glucose levels during fasting or low-carbohydrate intake.

Deficiencies in pyruvate decarboxylase can lead to metabolic disorders, such as pyruvate decarboxylase deficiency (PDC deficiency), which is characterized by lactic acidosis, developmental delays, and neurological issues. Proper diagnosis and management of these conditions often involve monitoring enzyme activity and glucose metabolism.

Acetates, in a medical context, most commonly refer to compounds that contain the acetate group, which is an functional group consisting of a carbon atom bonded to two hydrogen atoms and an oxygen atom (-COO-). An example of an acetate is sodium acetate (CH3COONa), which is a salt formed from acetic acid (CH3COOH) and is often used as a buffering agent in medical solutions.

Acetates can also refer to a group of medications that contain acetate as an active ingredient, such as magnesium acetate, which is used as a laxative, or calcium acetate, which is used to treat high levels of phosphate in the blood.

In addition, acetates can also refer to a process called acetylation, which is the addition of an acetyl group (-COCH3) to a molecule. This process can be important in the metabolism and regulation of various substances within the body.

An encyclopedia is a comprehensive reference work containing articles on various topics, usually arranged in alphabetical order. In the context of medicine, a medical encyclopedia is a collection of articles that provide information about a wide range of medical topics, including diseases and conditions, treatments, tests, procedures, and anatomy and physiology. Medical encyclopedias may be published in print or electronic formats and are often used as a starting point for researching medical topics. They can provide reliable and accurate information on medical subjects, making them useful resources for healthcare professionals, students, and patients alike. Some well-known examples of medical encyclopedias include the Merck Manual and the Stedman's Medical Dictionary.

In enzymology, a pyruvate oxidase (EC 1.2.3.3) is an enzyme that catalyzes the chemical reaction pyruvate + phosphate + O2 ⇌ {\ ... and phosphate-dependent pyruvate oxidase. This enzyme participates in pyruvate metabolism. It has 2 cofactors: FAD, and Thiamin ... Williams FR, Hager LP (1966). "Crystalline flavin pyruvate oxidase from Escherichia coli. I Isolation and properties of the ... and FAD-dependent pyruvate oxidase from Lactobacillus plantarum Kinetic coupling of intercofactor electron transfer with ...
More info for Family c.36.1.1: Pyruvate oxidase and decarboxylase. Timeline for Family c.36.1.1: Pyruvate oxidase and ... Family c.36.1.1: Pyruvate oxidase and decarboxylase appears in SCOP 1.59. *Family c.36.1.1: Pyruvate oxidase and decarboxylase ... Lineage for Family c.36.1.1: Pyruvate oxidase and decarboxylase. *Root: SCOP 1.57 *. Class c: Alpha and beta proteins (a/b) [ ... Family c.36.1.1: Pyruvate oxidase and decarboxylase first appeared (with stable ids) in SCOP 1.55. * ...
Russell, P., Schrock, H. L., & Gennis, R. B. (1977). Lipid activation and protease activation of pyruvate oxidase. Evidence ... Russell, P. ; Schrock, H. L. ; Gennis, R. B. / Lipid activation and protease activation of pyruvate oxidase. Evidence ... Lipid activation and protease activation of pyruvate oxidase. Evidence suggesting a common site of interaction on the protein. ... Russell, P, Schrock, HL & Gennis, RB 1977, Lipid activation and protease activation of pyruvate oxidase. Evidence suggesting a ...
An Escherichia coli mutant deficient in pyruvate oxidase activity due to altered phospholipid activation of the enzyme journal ... An Escherichia coli mutant deficient in pyruvate oxidase activity due to altered phospholipid activation of the enzyme journal ... A radical-chemical route to acetyl-CoA: the anaerobically induced pyruvate formate-lyase system of Escherichia coli journal, ... Metabolic rewiring of synthetic pyruvate dehydrogenase bypasses for acetone production in cyanobacteria journal, February 2020 ...
PDB Compounds: (A:) Pyruvate oxidase. SCOPe Domain Sequences for d2ez8a1:. Sequence; same for both SEQRES and ATOM records: ( ... Protein Pyruvate oxidase [52476] (2 species). binds FAD. *. Species Lactobacillus plantarum [TaxId:1590] [52477] (8 PDB entries ... Family c.31.1.3: Pyruvate oxidase and decarboxylase, middle domain [52475] (8 proteins). N-terminal domain is Pyr module, and C ... PDB Description: pyruvate oxidase variant f479w in complex with reaction intermediate 2-lactyl-thiamin diphosphate ...
The enzymatic assay targets alanine and employs alanine transaminase (ALT), pyruvate oxidase (POx), and horseradish peroxidase ...
Quasi-elastic light scattering studies on pyruvate oxidase. Raj, T., Russell, P., Flygare, W. H. & Gennis, R. B., Mar 15 1977, ... Regulation by Lipids of Cofactor Binding to a Peripheral Membrane Enzyme: Binding of Thiamin Pyrophosphate to Pyruvate Oxidase ...
glyoxylate oxidase. 1.2.3.6. pyruvate oxidase (CoA-acetylating). 1.2.3.7. indole-3-acetaldehyde oxidase. ...
Unexpected tautomeric equilibria of the carbanion-enamine intermediate in pyruvate oxidase highlight unrecognized chemical ... Meyer D, Walter L, Kolter G, Pohl M, Müller M, Tittmann K (2011) Conversion of pyruvate decarboxylase into an enantioselective ...
... pyruvate oxidase (EC 1.2.3.3)) and a reduction in the concentrations of glutathione and protein sulfhydryls in the blood and ... Effect on cytochrome oxidase Evidence has been presented that cytochrome oxidase (EC 1.9.3.1) activity may be significantly ... cytochrome oxidase, and a much higher sensitivity of cytochrome oxidase activity to cyanide (50% inhibition in vitro at 10-8M ( ... Increased glucose, pyruvate, and lactate concentrations in blood, liver, and brain were also found, immediately after the fifth ...
... but is not limited to glucose oxidase, glucose reductase, Lactate Oxidase, pyruvate oxidase or hydrogen peroxidase, wherein be ... Lactate Oxidase, pyruvate oxidase and hydrogen peroxidase. ... is exactly to utilize the glucose oxidase on the electrode to ... wherein said redox ferment is selected from the group that is made up of glucose oxidase, glucose reductase, ...
The stabilities of five proteins (phosphoglycerate kinase, PGK; pyruvate dehydrogenase E1.a, PDHA; NADH oxidase, NOX; enolase, ... Systems with single macromolecules in explicit solvent were built for phosphoglycerate kinase (PGK), pyruvate dehydrogenase E1. ... a (PDHA), NADH oxidase (NOX), enolase (ENO), translation initiation factor 1 (IF1), tRNA (ATRN), and acetate kinase (ACKA). PGK ... pyruvate kinase), TPIA (triosephosphate isomerase), GAPA (glyceraldehyde-3-phosphate dehydrogenase), PFKA (6- ...
The Staphylococcus aureus cidC gene encodes a pyruvate oxidase that affects acetate metabolism and cell death in stationary ... Reflected mainly by a 3 to 4-fold reduction in expression of the four cytochrome C oxidase genes (coxA-coxB-PA14_01310-coIII) ... Hence, in our experimental setup, S. aureus mainly produced energy from glycolysis and fermentation of pyruvate into lactate ( ... Genes for enzymes involved in conversion of pyruvate into formate (pflB) and acetoin (alsS, alsD) were repressed 6 and 10-fold ...
Urine organic acids, serum amino acids, porphyrins (porphyria), sulfites (sulfite oxidase deficiency and molybdenum co-factor ... deficiency), ammonia, lactate, pyruvate, carnitine profile. * Genetic testing (whole exome or epilepsy panel) for prolonged/ ...
In this scenario acetate synthesized from pyruvate with PoxB was apparently reutilized via Acs and the glyoxylate shunt enzymes ... Flores N, de Anda R, Flores S, Escalante A, Hernández G, Martínez A, Bolívar F: Role of pyruvate oxidase inEscherichia ... Specific activities of the pyruvate kinases in strains JM101 ΔpykA and JM101 ΔpykF respectively, grown on glycerol, as compared ... it is apparently responsible for the main pyruvate kinase activity in vivo. Finally, PYR is utilized by the pyruvate ...
The thiamine- and flavin-dependent peripheral membrane protein pyruvate oxidase from E. coli (EcPOX) catalyzes the oxidative ... It was shown that amino acids within the active site mediate pyruvate-induced reduction of the protein-bound flavin cofactor. ... the Activation Process and Coupling of Catalysis and Compartmentalization of the Peripheral Membrane Protein Pyruvate Oxidase ... the Activation Process and Coupling of Catalysis and Compartmentalization of the Peripheral Membrane Protein Pyruvate Oxidase ...
... pyruvate formate lyase (pflB), FAD-binding d-lactate dehydrogenase (dld), pyruvate oxidase (poxB), alcohol dehydrogenase (adhE ... pyruvate oxidase; pyruvate water dikinase; succinic acid; synthetase; unclassified drug; ackA gene; adhE gene; aerobic ...
pyruvate oxidase activity GO:0047112 * 2-hydroxyquinoline 8-monooxygenase activity GO:0033766 ...
Glucose was enzymatically determined; it was first oxidized in pyruvate in the presence of glucose oxidase (GOD), and the ...
Lindqvist Y, Schneider G: Thiamin diphosphate dependent enzymes: transketolase, pyruvate oxidase and pyruvate decarboxylase. ... an essential co-enzyme for the activity of key enzymes involved in C metabolism such as pyruvate carboxylase, pyruvate oxidase ... which could have an oxalate oxidase activity that generates H2O2 and CO2[23], may thus be involved in reducing oxidative stress ... Specific and constitutive expression of oxalate oxidase during the ageing of leaf sheaths of ryegrass stubble. Plant Cell ...
pyruvate kinase [3] (data from MRSA252). SAOUHSC_02849. pyruvate oxidase [3] (data from MRSA252). ... pyruvate dehydrogenase complex, E1 component subunit alpha [3] (data from MRSA252). SAOUHSC_01041. pyruvate dehydrogenase ...
Funciton: Pyruvate oxidase (EC 1.2.3.3) spxB. -89. 4.8. TTGTAATCGATTTCAA. LSA1188 Lactobacillus salivarius subsp. salivarius ...
pyruvate dehydrogenase E1 component, beta subunit [1] (data from MRSA252). NWMN_2438. (poxB). pyruvate oxidase [1] (data from ... pyruvate dehydrogenase E1 component, alpha subunit [1] (data from MRSA252). NWMN_0960. (phdB). ...
... preserved the expressions of mitochondrial key enzymes such as cytochrome c oxidase subunit 4 (COX IV) and pyruvate ...
PYR】Pyruvate Assay Kit (Pyruvate Oxidase Method). It is used to quantitatively determine the content of pyruvate (PYR) in human ...
RuBP carboxylase, PEPcase, Pyruvate dehydrogenase, ATPase, cytochrome oxidase, Hexokinase, Lactate dehydrogenase. Select/choose ... c) Pyruvate is formed in the mitochondrial matrix.. (d) There is complete breakdown of glucose in fermentation.. Answer:. (a) ... c) Cytochrome oxidase & enolase. (d) phosphoglyceromutase & triosephosphate isomerase. Answer:. (a) Aldolase & triosephosphate ... Pyruvate, which is formed by the glycolytic catabolism of carbohydrates undergoes oxidative phosphorylation. ...
... the pyruvate DH complex, a cytochrome c oxidase, solute binding proteins, porins, lipoproteins and others. However, these ...
Pyruvate Kinase in Potato Tubers Leads to a Decline in Pyruvate Resulting in an in Vivo Repression of the Alternative Oxidase. ...
Pyruvate Kinase in Potato Tubers Leads to a Decline in Pyruvate Resulting in an in Vivo Repression of the Alternative Oxidase. ...
Pyruvate Oxidase (1966-1972). Pyruvates (1966-1972). Public MeSH Note. 74. History Note. 74(73). Entry Combination. deficiency: ... A multienzyme complex responsible for the formation of ACETYL COENZYME A from pyruvate. The enzyme components are PYRUVATE ... A multienzyme complex responsible for the formation of ACETYL COENZYME A from pyruvate. The enzyme components are PYRUVATE ... Pyruvate Dehydrogenase Complex Preferred Term Term UI T034784. Date01/01/1999. LexicalTag NON. ThesaurusID NLM (1973). ...

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