An enzyme that catalyzes the oxidative decarboxylation of coproporphyrinogen III to protoporphyrinogen IX by the conversion of two propionate groups to two vinyl groups. It is the sixth enzyme in the 8-enzyme biosynthetic pathway of HEME, and is encoded by CPO gene. Mutations of CPO gene result in HEREDITARY COPROPORPHYRIA.
Porphyrinogens which are intermediates in the heme biosynthesis. They have four methyl and four propionic acid side chains attached to the pyrrole rings. Coproporphyrinogens I and III are formed in the presence of uroporphyrinogen decarboxylase from the corresponding uroporphyrinogen. They can yield coproporphyrins by autooxidation or protoporphyrin by oxidative decarboxylation.
Colorless reduced precursors of porphyrins in which the pyrrole rings are linked by methylene (-CH2-) bridges.
An autosomal dominant porphyria that is due to a deficiency of COPROPORPHYRINOGEN OXIDASE in the LIVER, the sixth enzyme in the 8-enzyme biosynthetic pathway of HEME. Clinical features include both neurological symptoms and cutaneous lesions. Patients excrete increased levels of porphyrin precursors, 5-AMINOLEVULINATE and COPROPORPHYRINS.
A membrane-bound flavoenzyme that catalyzes the oxygen-dependent aromatization of protoporphyrinogen IX (Protogen) to protoporphyrin IX (Proto IX). It is the last enzyme of the common branch of the HEME and CHLOROPHYLL pathways in plants, and is the molecular target of diphenyl ether-type herbicides. VARIEGATE PORPHYRIA is an autosomal dominant disorder associated with deficiency of protoporphyrinogen oxidase.
A mitochondrial enzyme found in a wide variety of cells and tissues. It is the final enzyme in the 8-enzyme biosynthetic pathway of HEME. Ferrochelatase catalyzes ferrous insertion into protoporphyrin IX to form protoheme or heme. Deficiency in this enzyme results in ERYTHROPOIETIC PROTOPORPHYRIA.
Porphyrins with four methyl and four propionic acid side chains attached to the pyrrole rings. Elevated levels of Coproporphyrin III in the urine and feces are major findings in patients with HEREDITARY COPROPORPHYRIA.
Porphyrins with four methyl, two vinyl, and two propionic acid side chains attached to the pyrrole rings. Protoporphyrin IX occurs in hemoglobin, myoglobin, and most of the cytochromes.
The class of all enzymes catalyzing oxidoreduction reactions. The substrate that is oxidized is regarded as a hydrogen donor. The systematic name is based on donor:acceptor oxidoreductase. The recommended name will be dehydrogenase, wherever this is possible; as an alternative, reductase can be used. Oxidase is only used in cases where O2 is the acceptor. (Enzyme Nomenclature, 1992, p9)
The color-furnishing portion of hemoglobin. It is found free in tissues and as the prosthetic group in many hemeproteins.
The removal of a carboxyl group, usually in the form of carbon dioxide, from a chemical compound.
A diverse group of metabolic diseases characterized by errors in the biosynthetic pathway of HEME in the LIVER, the BONE MARROW, or both. They are classified by the deficiency of specific enzymes, the tissue site of enzyme defect, or the clinical features that include neurological (acute) or cutaneous (skin lesions). Porphyrias can be hereditary or acquired as a result of toxicity to the hepatic or erythropoietic marrow tissues.
A compound produced from succinyl-CoA and GLYCINE as an intermediate in heme synthesis. It is used as a PHOTOCHEMOTHERAPY for actinic KERATOSIS.
An enzyme that catalyzes the decarboxylation of UROPORPHYRINOGEN III to coproporphyrinogen III by the conversion of four acetate groups to four methyl groups. It is the fifth enzyme in the 8-enzyme biosynthetic pathway of HEME. Several forms of cutaneous PORPHYRIAS are results of this enzyme deficiency as in PORPHYRIA CUTANEA TARDA; and HEPATOERYTHROPOIETIC PORPHYRIA.
Porphyrinogens which are intermediates in heme biosynthesis. They have four acetic acid and four propionic acid side chains attached to the pyrrole rings. Uroporphyrinogen I and III are formed from polypyrryl methane in the presence of uroporphyrinogen III cosynthetase and uroporphyrin I synthetase, respectively. They can yield uroporphyrins by autooxidation or coproporphyrinogens by decarboxylation.
A group of compounds containing the porphin structure, four pyrrole rings connected by methine bridges in a cyclic configuration to which a variety of side chains are attached. The nature of the side chain is indicated by a prefix, as uroporphyrin, hematoporphyrin, etc. The porphyrins, in combination with iron, form the heme component in biologically significant compounds such as hemoglobin and myoglobin.
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 group of metabolic diseases due to deficiency of one of a number of LIVER enzymes in the biosynthetic pathway of HEME. They are characterized by the accumulation and increased excretion of PORPHYRINS or its precursors. Clinical features include neurological symptoms (PORPHYRIA, ACUTE INTERMITTENT), cutaneous lesions due to photosensitivity (PORPHYRIA CUTANEA TARDA), or both (HEREDITARY COPROPORPHYRIA). Hepatic porphyrias can be hereditary or acquired as a result of toxicity to the hepatic tissues.
Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.
The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.
A collective genome representative of the many organisms, primarily microorganisms, existing in a community.
The full collection of microbes (bacteria, fungi, virus, etc.) that naturally exist within a particular biological niche such as an organism, soil, a body of water, etc.
Generally refers to the digestive structures stretching from the MOUTH to ANUS, but does not include the accessory glandular organs (LIVER; BILIARY TRACT; PANCREAS).
Constituent of 30S subunit prokaryotic ribosomes containing 1600 nucleotides and 21 proteins. 16S rRNA is involved in initiation of polypeptide synthesis.
One of the three domains of life (the others being Eukarya and ARCHAEA), also called Eubacteria. They are unicellular prokaryotic microorganisms which generally possess rigid cell walls, multiply by cell division, and exhibit three principal forms: round or coccal, rodlike or bacillary, and spiral or spirochetal. Bacteria can be classified by their response to OXYGEN: aerobic, anaerobic, or facultatively anaerobic; by the mode by which they obtain their energy: chemotrophy (via chemical reaction) or PHOTOTROPHY (via light reaction); for chemotrophs by their source of chemical energy: CHEMOLITHOTROPHY (from inorganic compounds) or chemoorganotrophy (from organic compounds); and by their source for CARBON; NITROGEN; etc.; HETEROTROPHY (from organic sources) or AUTOTROPHY (from CARBON DIOXIDE). They can also be classified by whether or not they stain (based on the structure of their CELL WALLS) with CRYSTAL VIOLET dye: gram-negative or gram-positive.
The relationships of groups of organisms as reflected by their genetic makeup.

Induction of coproporphyrinogen oxidase in Chlamydomonas chloroplasts occurs via transcriptional regulation of Cpx1 mediated by copper response elements and increased translation from a copper deficiency-specific form of the transcript. (1/92)

Coproporphyrinogen III oxidase, encoded by a single nuclear gene in Chlamydomonas reinhardtii, produces three distinct transcripts. One of these transcripts is greatly induced in copper-deficient cells by transcriptional activation, whereas the other forms are copper-insensitive. The induced form of the transcript was expressed coordinately with the cytochrome c6-encoding (Cyc6) gene, which is known to be transcriptionally regulated in copper-deficient cells. The sequence GTAC, which forms the core of a copper response element associated with the Cyc6 gene, is also essential for induction of the Cpx1 gene, suggesting that both are targets of the same signal transduction pathway. The constitutive and induced Cpx1 transcripts have the same half-lives in vivo, and all encode the same polypeptide with a chloroplast-targeting transit sequence, but the shortest one representing the induced form is a 2-4-fold better template for translation than are either of the constitutive forms. The enzyme remains localized to a soluble compartment in the chloroplast even in induced cells, and its abundance is not affected when the tetrapyrrole pathway is manipulated either genetically or by gabaculine treatment.  (+info)

Transcriptional control of Bacillus subtilis hemN and hemZ. (2/92)

Previous characterization of Bacillus subtilis hemN, encoding a protein involved in oxygen-independent coproporphyrinogen III decarboxylation, indicated the presence of a second hemN-like gene (B. Hippler, G. Homuth, T. Hoffmann, C. Hungerer, W. Schumann, and D. Jahn, J. Bacteriol. 179:7181-7185, 1997). The corresponding hemZ gene was found to be split into the two potential open reading frames yhaV and yhaW by a sequencing error of the genome sequencing project. The hemZ gene, encoding a 501-amino-acid protein with a calculated molecular mass of 57,533 Da, complemented a Salmonella typhimurium hemF hemN double mutant under aerobic and anaerobic growth conditions. A B. subtilis hemZ mutant accumulated coproporphyrinogen III under anaerobic growth conditions. A hemN hemZ double mutant exhibited normal aerobic and anaerobic growth, indicating the presence of a third alternative oxygen-independent enzymatic system for coproporphyrinogen III oxidation. The hemY gene, encoding oxygen-dependent protoporphyrinogen IX oxidase with coproporphyrinogen III oxidase side activity, did not significantly contribute to this newly identified system. Growth behavior of hemY mutants revealed the presence of an oxygen-independent protoporphyrinogen IX oxidase in B. subtilis. A monocistronic hemZ mRNA, starting 31 bp upstream of the translational start codon, was detected. Reporter gene fusions of hemZ and hemN demonstrated a fivefold anaerobic induction of both genes under nitrate ammonifying growth conditions. No anaerobic induction was observed for fermentatively growing B. subtilis. The B. subtilis redox regulatory systems encoded by resDE, fnr, and ywiD were indispensable for the observed transcriptional induction. A redox regulation cascade proceeding from an unknown sensor via resDE, through fnr and ywiD to hemN/hemZ, is suggested for the observed coregulation of heme biosynthesis and the anaerobic respiratory energy metabolism. Finally, only hemZ was found to be fivefold induced by the presence of H(2)O(2), indicating further coregulation of heme biosynthesis with the formation of the tetrapyrrole enzyme catalase.  (+info)

Coordinate copper- and oxygen-responsive Cyc6 and Cpx1 expression in Chlamydomonas is mediated by the same element. (3/92)

Chlamydomonas reinhardtii activates the transcription of the Cyc6 and the Cpx1 genes (encoding cytochrome c(6) and coprogen oxidase) in response to copper deficiency. Mutational analysis of promoter regions of the Cyc6 and Cpx1 genes revealed a four nucleotide sequence, GTAC, which was absolutely essential for copper responsiveness. The Cyc6 promoter contains two copper response elements, each with a functionally important GTAC sequence, whereas the Cpx1 promoter contains only one. This may contribute to the stronger and more tightly regulated expression of the Cyc6 gene. Mutation or deletion of sequences flanking the GTACs implicates additional nucleotides contributing to copper-responsive expression, but none are absolutely essential. Metal ion selectivity of Cpx1 expression is identical to that described previously for Cyc6 and is restricted to the copper deficiency-induced Cpx1 transcript. The Cyc6 and Cpx1 genes are also induced by oxygen deficiency. Reporter gene constructs indicate that the induction occurs at the level of transcription and requires the same GTAC sequence that is critical for copper responsiveness. We suggest that components of the copper-responsive signal transduction pathway are used for some of the changes in gene expression in hypoxic cells.  (+info)

Alcohol and porphyrin metabolism. (4/92)

Alcohol is a porphyrinogenic agent which may cause disturbances in porphyrin metabolism in healthy persons as well as biochemical and clinical manifestations of acute and chronic hepatic porphyrias. After excessive consumption of alcohol, a temporary, clinically asymptomatic secondary hepatic coproporphyrinuria is observable, which can become persistent in cases of alcohol-induced liver damage. Nowadays, the alcohol-liver-porphyrinuria syndrome is the first to be mentioned in secondary hepatic disturbances of porphyrin metabolism. Acute hepatic porphyrias (acute intermittent porphyria, variegate porphyria and hereditary coproporphyria) are considered to be molecular regulatory diseases, in contrast to non-acute, chronic hepatic porphyria, clinically appearing as porphyria cutanea tarda (PCT). Porphyrins do not accumulate in the liver in acute porphyrias, whereas in chronic hepatic porphyrias they do. Thus, chronic hepatic porphyria is a porphyrin-accumulation disease, whereas acute hepatic porphyrias are haem-pathway-dysregulation diseases, characterized in general by induction of delta-aminolevulinic acid synthase in the liver and excessive stimulation of the pathway without storage of porphyrins in the liver. The clinical expression of acute hepatic porphyrias can be triggered by alcohol, because alcohol augments the inducibility of delta-aminolevulinic acid synthase. In chronic hepatic porphyrias, however, which are already associated with liver damage, alcohol potentiates the disturbance of the decarboxylation of uro- and heptacarboxyporphyrinogen, which is followed by a hepatic accumulation of uro- and heptacarboxyporphyrin and their sometimes extreme urinary excretion. Especially in persons with a genetic deficiency of uroporphyrinogen decarboxylase, but also in patients with the so-called sporadic variety of PCT, alcohol is able to transform an asymptomatic coproporphyrinuria into PCT. Alcohol has many biochemical and clinical effects on porphyrin and haem synthesis both in humans and laboratory animals. Ethanol suppresses the activity of porphobilinogen synthase (synonym: delta-aminolevulinic acid dehydratase), uroporphyrinogen decarboxylase, coproporphyrinogen oxidase and ferrochelatase, whereas it induces the first and rate-limiting enzyme in the pathway, delta-aminolevulinic acid synthase and also porphobilinogen deaminase. Therefore, teetotalism is a therapeutically and prophylactically important measure in all types of hepatic porphyrias.  (+info)

Interacting regulatory circuits involved in orderly control of photosynthesis gene expression in Rhodobacter sphaeroides 2.4.1. (5/92)

FnrL, the homolog of the global anaerobic regulator Fnr, is required for the induction of the photosynthetic apparatus in Rhodobacter sphaeroides 2.4.1. Thus, the precise role of FnrL in photosynthesis (PS) gene expression and its interaction(s) with other regulators of PS gene expression are of considerable importance to our understanding of the regulatory circuitry governing spectral complex formation. Using a CcoP and FnrL double mutant strain, we obtained results which suggested that FnrL is not involved in the transduction of the inhibitory signal, by which PS gene expression is "silenced," emanating from the cbb(3) oxidase encoded by the ccoNOQP operon under aerobic conditions. The dominant effect of the ccoP mutation in the FnrL mutant strain with respect to spectral complex formation under aerobic conditions and restoration of a PS-positive phenotype suggested that inactivation of the cbb(3) oxidase to some extent bypasses the requirement for FnrL in the formation of spectral complexes. Additional analyses revealed that anaerobic induction of the bchE, hemN, and hemZ genes, which are involved in the tetrapyrrole biosynthetic pathways, requires FnrL. Thus, FnrL appears to be involved at multiple loci involved in the regulation of PS gene expression. Additionally, bchE was also shown to be regulated by the PrrBA two-component system, in conjunction with hemN and hemZ. These and other results to be discussed permit us to more accurately describe the role of FnrL as well as the interactions between the FnrL, PrrBA, and other regulatory circuits in the regulation of PS gene expression.  (+info)

The Crd1 gene encodes a putative di-iron enzyme required for photosystem I accumulation in copper deficiency and hypoxia in Chlamydomonas reinhardtii. (6/92)

Chlamydomonas reinhardtii adapts to copper deficiency by degrading apoplastocyanin and inducing Cyc6 and Cpx1 encoding cytochrome c(6) and coproporphyrinogen oxidase, respectively. To identify other components in this pathway, colonies resulting from insertional mutagenesis were screened for copper- conditional phenotypes. Twelve crd (copper response defect) strains were identified. In copper-deficient conditions, the crd strains fail to accumulate photosystem I and light-harvesting complex I, and they contain reduced amounts of light-harvesting complex II. Cyc6, Cpx1 expression and plastocyanin accumulation remain copper responsive. The crd phenotype is rescued by a similar amount of copper as is required for repression of Cyc6 and Cpx1 and for maintenance of plastocyanin at its usual stoichiometry, suggesting that the affected gene is a target of the same signal transduction pathway. The crd strains represent alleles at a single locus, CRD1, which encodes a 47 kDa, hydrophilic protein with a consensus carboxylate-bridged di-iron binding site. Crd1 homologs are present in the genomes of photosynthetic organisms. In Chlamydomonas, Crd1 expression is activated in copper- or oxygen-deficient cells, and Crd1 function is required for adaptation to these conditions.  (+info)

Regulation of the expression of human ferrochelatase by intracellular iron levels. (7/92)

Mammalian ferrochelatase, the terminal enzyme of the heme biosynthetic pathway, catalyzes the insertion of a ferrous ion into protoporphyrin and contains a labile [2Fe-2S] cluster center at the C-terminus. To clarify the roles of the iron-sulfur cluster in the expression of mammalian ferrochelatase, enzyme activity in human erythroleukemia K562 cells under iron-depleted conditions was examined. Treatment of cells with an iron chelator, desferrioxamine, resulted in a decrease in enzyme activity, in a dose- and time-dependent manner. Heme content decreased during desferrioxamine treatment of the cells. Addition of ferric ion-nitrilotriacetate [Fe (III)NTA] to desferrioxamine-containing cultures led to restoration of the reduction in the enzyme activity. While RNA blots showed that the amount of ferrochelatase mRNA remained unchanged during these treatments, the amount of ferrochelatase decreased with a concomitant decrease in enzyme activity. When full-length human ferrochelatase was expressed in Cos7 cells, the activity was found mainly in the mitochondria and was decreased markedly by treatment with desferrioxamine. The activity in Cos7 cells expressing human ferrochelatase in cytoplasm decreased with desferrioxamine, but to a lesser extent. When Escherichia coli ferrochelatase, which lacks the iron-sulfur cluster, was expressed in Cos7 cells, the activity did not change following any treatment. Conversely, the addition of Fe (III)NTA to the culture of K562 and Cos7 cells led to an increase in ferrochelatase activity. These results indicate that the expression of mammalian ferrochelatase is regulated by intracellular iron levels, via the iron-sulfur cluster center at the C-terminus, and this contributes to the regulation of the biosynthesis of heme at the terminal step.  (+info)

One of two hemN genes in Bradyrhizobium japonicum is functional during anaerobic growth and in symbiosis. (8/92)

Previously, we screened the symbiotic gene region of the Bradyrhizobium japonicum chromosome for new NifA-dependent genes by competitive DNA-RNA hybridization (A. Nienaber, A. Huber, M. Gottfert, H. Hennecke, and H. M. Fischer, J. Bacteriol. 182:1472-1480, 2000). Here we report more details on one of the genes identified, a hemN-like gene (now called hemN(1)) whose product exhibits significant similarity to oxygen-independent coproporphyrinogen III dehydrogenases involved in heme biosynthesis in facultatively anaerobic bacteria. In the course of these studies, we discovered that B. japonicum possesses a second hemN-like gene (hemN(2)), which was then cloned by using hemN(1) as a probe. The hemN(2) gene maps outside of the symbiotic gene region; it is located 1.5 kb upstream of nirK, the gene for a Cu-containing nitrite reductase. The two deduced HemN proteins are similar in size (445 and 450 amino acids for HemN(1) and HemN(2), respectively) and share 53% identical (68% similar) amino acids. Expression of both hemN genes was monitored with the help of chromosomally integrated translational lacZ fusions. No significant expression of either gene was detected in aerobically grown cells, whereas both genes were strongly induced (> or = 20-fold) under microaerobic or anaerobic conditions. Induction was in both cases dependent on the transcriptional activator protein FixK(2). In addition, maximal anaerobic hemN(1) expression was partially dependent on NifA, which explains why this gene had been identified by the competitive DNA-RNA hybridization approach. Strains were constructed carrying null mutations either in individual hemN genes or simultaneously in both genes. All mutants showed normal growth in rich medium under aerobic conditions. Unlike the hemN(1) mutant, strains lacking a functional hemN(2) gene were unable to grow anaerobically under nitrate-respiring conditions and largely failed to fix nitrogen in symbiosis with the soybean host plant. Moreover, these mutants lacked several c-type cytochromes which are normally detectable by heme staining of proteins from anaerobically grown wild-type cells. Taken together, our results revealed that B. japonicum hemN(2), but not hemN(1), encodes a protein that is functional under the conditions tested, and this conclusion was further corroborated by the successful complementation of a Salmonella enterica serovar Typhimurium hemF hemN mutant with hemN(2) only.  (+info)

Coproporphyrinogen Oxidase is a mitochondrial enzyme that plays a crucial role in the biosynthesis of heme, which is an essential component of hemoglobin and other hemoproteins. This enzyme catalyzes the oxidative decarboxylation of coproporphyrinogen III to protoporphyrinogen IX, a key step in the heme biosynthetic pathway.

Deficiency or dysfunction of Coproporphyrinogen Oxidase can lead to a rare genetic disorder known as Hereditary Coproporphyria (HCP), which is characterized by the accumulation of coproporphyrinogen III and its derivative, coproporphyrin, in various tissues and body fluids. This accumulation can result in a range of symptoms, including abdominal pain, neurological disturbances, and skin manifestations.

Coproporphyrinogens are intermediates in the biosynthesis of heme, a complex molecule that is essential for various biological processes including oxygen transport and cellular respiration. There are two types of coproporphyrinogens: Coproporphyrinogen I and Coproporphyrinogen III.

Coproporphyrinogen I is an intermediate in the biosynthesis of siroheme, a porphyrin-like molecule that functions as a cofactor for enzymes involved in sulfur and nitrogen metabolism. It is produced from uroporphyrinogen III through the action of coproporphyrinogen oxidase.

Coproporphyrinogen III, on the other hand, is an intermediate in the biosynthesis of heme. It is produced from protoporphyrinogen IX through the action of coproporphyrinogen oxidase and then converted to protoporphyrin IX by the enzyme coproporphyrinogen III decarboxylase. Protoporphyrin IX is then converted to heme by the addition of iron in a reaction catalyzed by ferrochelatase.

Abnormal accumulation of coproporphyrinogens can occur due to various genetic and acquired disorders that affect enzymes involved in heme biosynthesis, leading to the accumulation of porphyrins and their precursors in tissues and bodily fluids. These conditions are known as porphyrias and can present with a variety of symptoms including neuropsychiatric manifestations, skin lesions, and gastrointestinal disturbances.

Porphyrinogens are organic compounds that are the precursors to porphyrins, which are ring-shaped molecules found in many important biological molecules such as hemoglobin and cytochromes. Porphyrinogens are themselves derived from the condensation of four pyrrole molecules, and they undergo further reactions to form porphyrins.

In particular, porphyrinogens are intermediates in the biosynthesis of heme, which is a complex organic ring-shaped molecule that contains iron and plays a critical role in oxygen transport and storage in the body. Abnormalities in heme biosynthesis can lead to various medical conditions known as porphyrias, which are characterized by the accumulation of porphyrinogens and other intermediates in this pathway. These conditions can cause a range of symptoms, including neurological problems, skin sensitivity to light, and abdominal pain.

Hereditary coproporphyria (HCP) is a rare inherited disorder of the heme biosynthesis pathway, which is the process by which your body produces heme. Heme is a crucial component of various proteins, including hemoglobin, which carries oxygen in red blood cells.

In HCP, there is a deficiency of an enzyme called coproporphyrinogen oxidase. This enzyme is essential for converting coproporphyrinogen III to protoporphyrin IX in the heme biosynthesis pathway. As a result, coproporphyrinogen III accumulates and gets converted to coproporphyrin, which is excreted in urine and stool in abnormally high amounts.

The symptoms of HCP can be diverse and may include both neurological and gastrointestinal manifestations. Neurological symptoms might include abdominal pain, muscle weakness, numbness, tingling, seizures, and psychiatric disturbances. Gastrointestinal symptoms could encompass nausea, vomiting, constipation, or diarrhea. These symptoms are typically triggered by certain factors such as infections, drugs, hormonal changes, or alcohol consumption.

HCP is usually inherited in an autosomal dominant manner, meaning that a child has a 50% chance of inheriting the disease-causing gene from a parent with the disorder. However, some cases may result from de novo mutations, which means the mutation occurs spontaneously without a family history of the condition.

Diagnosis of HCP is usually made through measuring porphyrin levels and their precursors in urine, stool, and blood during an acute attack or between attacks. Genetic testing can confirm the diagnosis by identifying mutations in the CPOX gene, which encodes coproporphyrinogen oxidase.

Treatment for HCP typically involves avoiding triggers, providing supportive care during acute attacks, and using medications to manage symptoms. In some cases, heme arginate or hemine may be given to help decrease porphyrin precursor production. Preventive measures such as avoidance of potential triggers, adequate hydration, and a balanced diet are essential in managing HCP.

Protoporphyrinogen Oxidase (PPO) is a mitochondrial enzyme that plays a crucial role in the heme biosynthesis pathway. It catalyzes the oxidation of protoporphyrinogen IX to protporphyrin IX, which is the penultimate step in the production of heme. This enzyme is the target of certain herbicides, such as those containing the active ingredient diphenyl ether, and genetic deficiencies in PPO can lead to a rare genetic disorder called Protoporphyria.

Ferrochelatase is a medical/biochemical term that refers to an enzyme called Fe-chelatase or heme synthase. This enzyme plays a crucial role in the biosynthesis of heme, which is a vital component of hemoglobin, cytochromes, and other important biological molecules.

Ferrochelatase functions by catalyzing the insertion of ferrous iron (Fe2+) into protoporphyrin IX, the final step in heme biosynthesis. This enzyme is located within the inner mitochondrial membrane of cells and is widely expressed in various tissues, with particularly high levels found in erythroid precursor cells, liver, and brain.

Defects or mutations in the ferrochelatase gene can lead to a rare genetic disorder called erythropoietic protoporphyria (EPP), which is characterized by an accumulation of protoporphyrin IX in red blood cells, plasma, and other tissues. This accumulation results in photosensitivity, skin lesions, and potential complications such as liver dysfunction and gallstones.

Coproporphyrins are porphyrin molecules that contain four carboxylic acid groups (four propionic side chains and two acetic side chains). They are intermediates in the biosynthesis of heme, which is a component of hemoglobin and other hemoproteins. Coproporphyrins can be further metabolized to form protoporphyrins, which are converted into heme by the enzyme ferrochelatase.

Coproporphyrins can be excreted in urine and feces, and their levels can be measured in clinical testing. Elevated coproporphyrin levels in urine or feces may indicate the presence of certain medical conditions, such as lead poisoning, porphyrias, or liver dysfunction.

There are two types of coproporphyrins, coproporphyrin I and coproporphyrin III, which differ in the arrangement of their side chains. Coproporphyrin III is the form that is normally produced in the body, while coproporphyrin I is a byproduct of abnormal porphyrin metabolism.

Protoporphyrins are organic compounds that are the immediate precursors to heme in the porphyrin synthesis pathway. They are composed of a porphyrin ring, which is a large, complex ring made up of four pyrrole rings joined together, with an acetate and a propionate side chain at each pyrrole. Protoporphyrins are commonly found in nature and are important components of many biological systems, including hemoglobin, the protein in red blood cells that carries oxygen throughout the body.

There are several different types of protoporphyrins, including protoporphyrin IX, which is the most common form found in humans and other animals. Protoporphyrins can be measured in the blood or other tissues as a way to diagnose or monitor certain medical conditions, such as lead poisoning or porphyrias, which are rare genetic disorders that affect the production of heme. Elevated levels of protoporphyrins in the blood or tissues can indicate the presence of these conditions and may require further evaluation and treatment.

Oxidoreductases are a class of enzymes that catalyze oxidation-reduction reactions, which involve the transfer of electrons from one molecule (the reductant) to another (the oxidant). These enzymes play a crucial role in various biological processes, including energy production, metabolism, and detoxification.

The oxidoreductase-catalyzed reaction typically involves the donation of electrons from a reducing agent (donor) to an oxidizing agent (acceptor), often through the transfer of hydrogen atoms or hydride ions. The enzyme itself does not undergo any permanent chemical change during this process, but rather acts as a catalyst to lower the activation energy required for the reaction to occur.

Oxidoreductases are classified and named based on the type of electron donor or acceptor involved in the reaction. For example, oxidoreductases that act on the CH-OH group of donors are called dehydrogenases, while those that act on the aldehyde or ketone groups are called oxidases. Other examples include reductases, peroxidases, and catalases.

Understanding the function and regulation of oxidoreductases is important for understanding various physiological processes and developing therapeutic strategies for diseases associated with impaired redox homeostasis, such as cancer, neurodegenerative disorders, and cardiovascular disease.

Heme is not a medical term per se, but it is a term used in the field of medicine and biology. Heme is a prosthetic group found in hemoproteins, which are proteins that contain a heme iron complex. This complex plays a crucial role in various biological processes, including oxygen transport (in hemoglobin), electron transfer (in cytochromes), and chemical catalysis (in peroxidases and catalases).

The heme group consists of an organic component called a porphyrin ring, which binds to a central iron atom. The iron atom can bind or release electrons, making it essential for redox reactions in the body. Heme is also vital for the formation of hemoglobin and myoglobin, proteins responsible for oxygen transport and storage in the blood and muscles, respectively.

In summary, heme is a complex organic-inorganic structure that plays a critical role in several biological processes, particularly in electron transfer and oxygen transport.

Decarboxylation is a chemical reaction that removes a carboxyl group from a molecule and releases carbon dioxide (CO2) as a result. In the context of medical chemistry, decarboxylation is a crucial process in the activation of certain acidic precursor compounds into their biologically active forms.

For instance, when discussing phytocannabinoids found in cannabis plants, decarboxylation converts non-psychoactive tetrahydrocannabinolic acid (THCA) into psychoactive delta-9-tetrahydrocannabinol (Δ9-THC) through the removal of a carboxyl group. This reaction typically occurs when the plant material is exposed to heat, such as during smoking or vaporization, or when it undergoes aging.

In summary, decarboxylation refers to the chemical process that removes a carboxyl group from a molecule and releases CO2, which can activate certain acidic precursor compounds into their biologically active forms in medical chemistry.

Porphyrias are a group of rare genetic disorders that affect the production of heme, a component in hemoglobin that carries oxygen in the blood. The diseases are caused by mutations in the genes involved in the production of heme, leading to the buildup of porphyrins or their precursors in the body. These substances can be toxic and can cause various symptoms depending on the specific type of porphyria. Symptoms may include abdominal pain, neurological problems, and skin issues. Porphyrias are typically divided into two categories: acute porphyrias, which affect the nervous system, and cutaneous porphyrias, which primarily affect the skin.

Aminolevulinic acid (ALA) is a naturally occurring compound in the human body and is a key precursor in the biosynthesis of heme, which is a component of hemoglobin in red blood cells. It is also used as a photosensitizer in dermatology for the treatment of certain types of skin conditions such as actinic keratosis and basal cell carcinoma.

In medical terms, ALA is classified as an α-keto acid and a porphyrin precursor. It is synthesized in the mitochondria from glycine and succinyl-CoA in a reaction catalyzed by the enzyme aminolevulinic acid synthase. After its synthesis, ALA is transported to the cytosol where it undergoes further metabolism to form porphyrins, which are then used for heme biosynthesis in the mitochondria.

In dermatology, topical application of ALA followed by exposure to a specific wavelength of light can lead to the production of reactive oxygen species that destroy abnormal cells in the skin while leaving healthy cells unharmed. This makes it an effective treatment for precancerous and cancerous lesions on the skin.

It is important to note that ALA can cause photosensitivity, which means that patients who have undergone ALA-based treatments should avoid exposure to sunlight or other sources of bright light for a period of time after the treatment to prevent adverse reactions.

Uroporphyrinogen decarboxylase is a vital enzyme in the biosynthetic pathway of heme, which is a crucial component of hemoglobin in red blood cells. This enzyme is responsible for catalyzing the decarboxylation of uroporphyrinogen III, a colorless porphyrinogen, to produce coproporphyrinogen III, a brownish-red porphyrinogen.

The reaction involves the sequential removal of four carboxyl groups from the four acetic acid side chains of uroporphyrinogen III, resulting in the formation of coproporphyrinogen III. This enzyme's activity is critical for the normal biosynthesis of heme, and any defects or deficiencies in its function can lead to various porphyrias, a group of metabolic disorders characterized by the accumulation of porphyrins and their precursors in the body.

The gene responsible for encoding uroporphyrinogen decarboxylase is UROD, located on chromosome 1p34.1. Mutations in this gene can lead to a deficiency in the enzyme's activity, causing an autosomal recessive disorder known as congenital erythropoietic porphyria (CEP), also referred to as Günther's disease. This condition is characterized by severe photosensitivity, hemolytic anemia, and scarring or thickening of the skin.

Uroporphyrinogens are organic compounds that are intermediate products in the synthesis of heme, which is a crucial component of hemoglobin and other important molecules in the body. Specifically, uroporphyrinogens are tetrapyrroles, which means they contain four pyrrole rings linked together. They have eight carboxylic acid side chains and two propionic acid side chains.

There are two types of uroporphyrinogens: Type I and Type III. Uroporphyrinogen III is the precursor to heme, while uroporphyrinogen I is a dead-end metabolite that is not used in heme synthesis. Defects in the enzymes involved in heme biosynthesis can lead to various porphyrias, which are genetic disorders characterized by the accumulation of porphyrins and their precursors in the body.

Porphyrins are complex organic compounds that contain four pyrrole rings joined together by methine bridges (=CH-). They play a crucial role in the biochemistry of many organisms, as they form the core structure of various heme proteins and other metalloproteins. Some examples of these proteins include hemoglobin, myoglobin, cytochromes, and catalases, which are involved in essential processes such as oxygen transport, electron transfer, and oxidative metabolism.

In the human body, porphyrins are synthesized through a series of enzymatic reactions known as the heme biosynthesis pathway. Disruptions in this pathway can lead to an accumulation of porphyrins or their precursors, resulting in various medical conditions called porphyrias. These disorders can manifest as neurological symptoms, skin lesions, and gastrointestinal issues, depending on the specific type of porphyria and the site of enzyme deficiency.

It is important to note that while porphyrins are essential for life, their accumulation in excessive amounts or at inappropriate locations can result in pathological conditions. Therefore, understanding the regulation and function of porphyrin metabolism is crucial for diagnosing and managing porphyrias and other related disorders.

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.

Hepatic porphyrias are a group of rare genetic disorders that affect the production of heme in the liver. Heme is a crucial component of hemoglobin, the protein in red blood cells that carries oxygen throughout the body. In hepatic porphyrias, there is a buildup of porphyrins or porphyrin precursors, which are toxic and can cause a variety of symptoms.

The four types of hepatic porphyrias are:

1. Acute Intermittent Porphyria (AIP): This is the most common type of hepatic porphyria. It is characterized by attacks of abdominal pain, nausea, vomiting, constipation, and neurological symptoms such as muscle weakness, seizures, and mental changes.
2. Variegate Porphyria (VP): This type of porphyria is more common in South Africa but can occur worldwide. It is characterized by skin symptoms such as blistering and scarring after exposure to sunlight, as well as acute attacks similar to those seen in AIP.
3. Hereditary Coproporphyria (HCP): This type of porphyria is similar to VP, but the symptoms are usually less severe. It can cause both skin symptoms and acute attacks.
4. ALA Dehydratase Deficiency Porphyria (ADDP): This is the rarest type of hepatic porphyria. It is characterized by severe neurological symptoms and is often diagnosed in infancy or early childhood.

The diagnosis of hepatic porphyrias typically involves measuring the levels of porphyrins and their precursors in the urine, blood, or stool during an attack or between attacks. Treatment may include avoiding trigger factors such as certain medications, alcohol, and smoking, as well as providing supportive care during acute attacks. In some cases, medication to reduce porphyrin production or prevent attacks may be necessary.

Molecular sequence data refers to the specific arrangement of molecules, most commonly nucleotides in DNA or RNA, or amino acids in proteins, that make up a biological macromolecule. This data is generated through laboratory techniques such as sequencing, and provides information about the exact order of the constituent molecules. This data is crucial in various fields of biology, including genetics, evolution, and molecular biology, allowing for comparisons between different organisms, identification of genetic variations, and studies of gene function and regulation.

An amino acid sequence is the specific order of amino acids in a protein or peptide molecule, formed by the linking of the amino group (-NH2) of one amino acid to the carboxyl group (-COOH) of another amino acid through a peptide bond. The sequence is determined by the genetic code and is unique to each type of protein or peptide. It plays a crucial role in determining the three-dimensional structure and function of proteins.

A metagenome is the collective genetic material contained within a sample taken from a specific environment, such as soil or water, or within a community of organisms, like the microbiota found in the human gut. It includes the genomes of all the microorganisms present in that environment or community, including bacteria, archaea, fungi, viruses, and other microbes, whether they can be cultured in the lab or not. By analyzing the metagenome, scientists can gain insights into the diversity, abundance, and functional potential of the microbial communities present in that environment.

Medical Definition of Microbiota:

The community of microorganisms, including bacteria, viruses, fungi, and other microscopic life forms, that inhabit a specific environment or body part. In the human body, microbiota can be found on the skin, in the mouth, gut, and other areas. The largest concentration of microbiota is located in the intestines, where it plays an essential role in digestion, immune function, and overall health.

The composition of the microbiota can vary depending on factors such as age, diet, lifestyle, genetics, and environmental exposures. Dysbiosis, or imbalance of the microbiota, has been linked to various health conditions, including gastrointestinal disorders, allergies, autoimmune diseases, and neurological disorders.

Therefore, maintaining a healthy and diverse microbiota is crucial for overall health and well-being. This can be achieved through a balanced diet, regular exercise, adequate sleep, stress management, and other lifestyle practices that support the growth and maintenance of beneficial microorganisms in the body.

The gastrointestinal (GI) tract, also known as the digestive tract, is a continuous tube that starts at the mouth and ends at the anus. It is responsible for ingesting, digesting, absorbing, and excreting food and waste materials. The GI tract includes the mouth, esophagus, stomach, small intestine (duodenum, jejunum, ileum), large intestine (cecum, colon, rectum, anus), and accessory organs such as the liver, gallbladder, and pancreas. The primary function of this system is to process and extract nutrients from food while also protecting the body from harmful substances, pathogens, and toxins.

Ribosomal RNA (rRNA) is a type of RNA that combines with proteins to form ribosomes, which are complex structures inside cells where protein synthesis occurs. The "16S" refers to the sedimentation coefficient of the rRNA molecule, which is a measure of its size and shape. In particular, 16S rRNA is a component of the smaller subunit of the prokaryotic ribosome (found in bacteria and archaea), and is often used as a molecular marker for identifying and classifying these organisms due to its relative stability and conservation among species. The sequence of 16S rRNA can be compared across different species to determine their evolutionary relationships and taxonomic positions.

Bacteria are single-celled microorganisms that are among the earliest known life forms on Earth. They are typically characterized as having a cell wall and no membrane-bound organelles. The majority of bacteria have a prokaryotic organization, meaning they lack a nucleus and other membrane-bound organelles.

Bacteria exist in diverse environments and can be found in every habitat on Earth, including soil, water, and the bodies of plants and animals. Some bacteria are beneficial to their hosts, while others can cause disease. Beneficial bacteria play important roles in processes such as digestion, nitrogen fixation, and biogeochemical cycling.

Bacteria reproduce asexually through binary fission or budding, and some species can also exchange genetic material through conjugation. They have a wide range of metabolic capabilities, with many using organic compounds as their source of energy, while others are capable of photosynthesis or chemosynthesis.

Bacteria are highly adaptable and can evolve rapidly in response to environmental changes. This has led to the development of antibiotic resistance in some species, which poses a significant public health challenge. Understanding the biology and behavior of bacteria is essential for developing strategies to prevent and treat bacterial infections and diseases.

Phylogeny is the evolutionary history and relationship among biological entities, such as species or genes, based on their shared characteristics. In other words, it refers to the branching pattern of evolution that shows how various organisms have descended from a common ancestor over time. Phylogenetic analysis involves constructing a tree-like diagram called a phylogenetic tree, which depicts the inferred evolutionary relationships among organisms or genes based on molecular sequence data or other types of characters. This information is crucial for understanding the diversity and distribution of life on Earth, as well as for studying the emergence and spread of diseases.

Coproporphyrinogen-III oxidase, mitochondrial (abbreviated as CPOX) is an enzyme that in humans is encoded by the CPOX gene. A ... Coproporphyrinogen+III+Oxidases at the U.S. National Library of Medicine Medical Subject Headings (MeSH) Portal: Biology This ... Guo R, Lim CK, Peters TJ (October 1988). "Accurate and specific HPLC assay of coproporphyrinogen III oxidase activity in human ... Madsen O, Sandal L, Sandal NN, Marcker KA (October 1993). "A soybean coproporphyrinogen oxidase gene is highly expressed in ...
Layer G, Moser J, Heinz DW, Jahn D, Schubert WD (2003). "Crystal structure of coproporphyrinogen III oxidase reveals cofactor ... Layer G, Verfurth K, Mahlitz E, Jahn D (2002). "Oxygen-independent coproporphyrinogen-III oxidase HemN from Escherichia coli". ... Importantly, only HemN utilizes S-adenosyl Methionine (SAM). Human variants of Coproporphyrinogen oxidase are cofactor- ... HemN is the Oxygen-independent oxidase produced in E. coli. HemF is the oxygen-dependent oxidase within E. coli. ...
"Four novel mutations of the coproporphyrinogen III oxidase gene". Cellular and Molecular Biology. 55 (1): 8-15. PMID 19267996. ... coproporphyrinogen oxidase (deficiency causes hereditary coproporphyria) FECH: ferrochelatase (deficiency causes erythropoietic ... Thus cytochrome oxidase, which has two A hemes (heme a and heme a3) in its structure, contains two moles of heme A per mole ... Caughey, W. S.; Smythe, G. E.; O'Keeffe, D. H.; Maskasky, J. E.; Smith, M. L. (1975). "Heme A of Cytochrome c Oxidase: ...
"Characterization of coproporphyrinogen III oxidase in Plasmodium falciparum cytosol". Parasitology International. 59 (2): 121- ...
HemN or anaerobic coproporphyrinogen III oxidase is a radical SAM enzyme that catalyzes the oxidative decarboxylation of ... oxygen-independent coproporphyrinogen III oxidase (cofactor biosynthesis - heme) HmdB - 5,10-methenyltetrahydromethanopterin ... "Revisiting the Mechanism of the Anaerobic Coproporphyrinogen III Oxidase HemN". Angewandte Chemie. 58 (19): 6235-6238. doi: ... These enzymes contain both the radical SAM motif and exhibit striking sequence similarity to coproporhyrinogen III oxidase ( ...
HCP is caused by a deficiency of the enzyme coproporphyrinogen oxidase, coded for by the CPOX gene, and is inherited in an ... There is no cure for HCP caused by the deficient activity of coproporphyrinogen oxidase. Treatment of the acute symptoms of HCP ... HCP is caused by mutations in CPOX, which codes for the enzyme coproporphyrinogen oxidase. This enzyme is responsible for the ... ISBN 978-3-642-15719-6. "Homo sapiens coproporphyrinogen oxidase, mRNA (cDNA clone MGC:19736 IMAGE:3607724), complete cds". US ...
Madsen O, Sandal L, Sandal NN, Marcker KA (October 1993). "A soybean coproporphyrinogen oxidase gene is highly expressed in ...
... may refer to: Coproporphyrinogen III oxidase Catalytic partial oxidation This disambiguation page lists articles ...
... is further used as a substrate for the enzyme coproporphyrinogen III oxidase which oxidizes and further ... For comparison, coproporphyrinogen I has them in the sequence MP-MP-MP-MP. heme. In the main porphyrin biosynthesis pathway, ... Coproporphyrinogen III is a metabolic intermediate in the biosynthesis of many compounds that are critical for living organisms ... coproporphyrinogen III is derived from uroporphyrinogen III by the action of the enzyme uroporphyrinogen III decarboxylase: The ...
Enzyme tests show markedly reduced activity of coproporphyrinogen oxidase, compared to both unaffected individuals and those ...
Genes encoding coproporphyrinogen oxidase, an essential enzyme in the heme biosynthetic pathway were found as well as genes ...
... and it is converted into protoporphyrinogen IX by coproporphyrinogen III oxidase. Coproporphyrinogens at the U.S. National ... Coproporphyrinogen III is the most common variance. In the metabolism of porphyrin, it is formed from uroporphyrinogen III by ... Library of Medicine Medical Subject Headings (MeSH) PubChem - Coproporphyrinogen III v t e (All stub articles, Biochemistry ...
Hereditary coproporphyria, which is characterized by a deficiency in coproporphyrinogen oxidase, coded for by the CPOX gene, ... Variegate porphyria (also porphyria variegata or mixed porphyria), which results from a partial deficiency in PROTO oxidase, ...
... coproporphyrinogen oxidase FECH: ferrochelatase (protoporphyria) HMBS: hydroxymethylbilane synthase PPOX: protoporphyrinogen ... Protoporphyrinogen oxidase or protox is an enzyme that in humans is encoded by the PPOX gene. Protoporphyrinogen oxidase is ... Inhibition of protoporphyrinogen oxidase is a mechanism of action for several commercial herbicides including the nitrophenyl ... "Entrez Gene: PPOX protoporphyrinogen oxidase". Brzezowski P, Ksas B, Havaux M, Grimm B, Chazaux M, Peltier G, et al. (2019-05- ...
... coproporphyrinogen oxidase (coproporphyria, harderoporphyria) DPPA2: Developmental pluripotency associated 2 DTX3L: encoding ... homogentisate oxidase) IFT122: intraflagellar transport gene 122 KIAA1257: KIAA1257 LINC01279: encoding protein long intergenic ...
The compound is synthesized in most organisms from coproporphyrinogen III by the enzyme coproporphyrinogen oxidase: The process ... In coproporphyrinogen III, the substituents on the pyrrole rings have the arrangement MP-MP-MP-PM, where M and P are methyl and ... Protoporphyrinogen oxidase v t e (Articles without InChI source, Chemical pages without ChemSpiderID, Articles without EBI ... By the action of protoporphyrinogen oxidase, protoporphyrinogen IX is later converted into protoporphyrin IX, the first colored ...
Class C methylase has homologous sequence with the RS enzyme, coproporphyrinogen III oxidase (HemN), which also catalyzes the ...
... coproporphyrinogen III oxidase, and PBP1A family penicillin-binding protein. These molecular signatures provide a reliable ... oxygen-independent coproporphyrinogen III oxidase, putative hydrolase MhqD, helix-turn-helix transcriptional regulator, tRNA ...
... coproporphyrinogen oxidase MeSH D08.811.682.660.275 - dihydrodipicolinate reductase MeSH D08.811.682.660.300 - dihydroorotate ... sarcosine oxidase MeSH D08.811.682.662.640 - proline oxidase MeSH D08.811.682.662.680 - pyridoxamine-phosphate oxidase MeSH ... d-amino-acid oxidase MeSH D08.811.682.664.500.261 - d-aspartate oxidase MeSH D08.811.682.664.500.398 - glutamate dehydrogenase ... proline oxidase MeSH D08.811.682.664.500.848 - protein-lysine 6-oxidase MeSH D08.811.682.664.500.924 - valine dehydrogenase ( ...
... coproporphyrinogen oxidase EC protoporphyrinogen oxidase EC bilirubin oxidase EC acyl-CoA oxidase EC ... D-aspartate oxidase EC L-amino-acid oxidase EC D-amino-acid oxidase EC monoamine oxidase EC ... aldehyde oxidase EC Now EC, xanthine oxidase EC pyruvate oxidase EC oxalate oxidase EC 1.2. ... glycine oxidase EC L-lysine 6-oxidase EC primary-amine oxidase EC diamine oxidase EC 7- ...
... precursor to coproporphyrinogen III. coproporphyrinogen III, precursor to protoporphyrinogen IX. Protoporphyrinogen IX, ... the parent porphyrinogen is dehydrogenated by protoporphyrinogen oxidase. Because of their limited delocalization, ...
4-hydroxyphenylpyruvate oxidase - 4-Nitrophenol 4-monooxygenase - 4933425L06Rik - 5' end - 5' flanking region - 5-pyridoxate ... coproporphyrinogen dehydrogenase - cortisone alpha-reductase - cosmid - costunolide synthase - CpG - craniosynostosis - crp ... menaquinol oxidase (H+-transporting) - Johann Mendel - Mendelian inheritance - message - messenger RNA - metaphase - ...
  • Coproporphyrinogen-III oxidase, mitochondrial (abbreviated as CPOX) is an enzyme that in humans is encoded by the CPOX gene. (
  • CPOX, the sixth enzyme of the haem biosynthetic pathway, converts coproporphyrinogen III to protoporphyrinogen IX through two sequential steps of oxidative decarboxylation. (
  • CPOX is an enzyme involved in the sixth step of porphyrin metabolism it catalyses the oxidative decarboxylation of coproporphyrinogen III to proto-porphyrinogen IX in the haem and chlorophyll biosynthetic pathways. (
  • HCP and VP result from a partial enzymatic deficiency of coproporphyrinogen oxidase (CPOX) and protoporphyrinogen oxidase (PPOX), respectively. (
  • The coproporphinogen oxidase gene is a enzyme that converts coproporphyrinogen III to protoporphyrinogen IX (OMIM). (
  • Hereditary coproporphyria is the result of a point mutation in the coproporphinogen oxidase (CPO) gene (OMIM). (
  • Publications] Shigeru Sassa: 'Molecular cletects of the coproporphyrinogen oxidase gene in hereditary coproporphyria. (
  • Variegate porphyria (VP) is an inherited disorder of porphyrin-heme metabolism arising from mutations of the gene encoding the enzyme protoporphyrinogen oxidase. (
  • Variegate porphyria arises from autosomal dominant inheritance of a gene mutation encoding a defective protoporphyrinogen oxidase enzyme. (
  • To date, there have been 184 different mutations in the protoporphyrinogen oxidase gene that results in variegate porphyria. (
  • Prevalence is estimated at 1 case in 300 persons in South Africa, where a protoporphyrinogen oxidase gene "founder" mutation traceable to Dutch immigrants who married there in 1680 has been widely disseminated. (
  • This relatively high prevalence compared with Europe suggests a possible protoporphyrinogen oxidase gene mutation passed down through Jewish ancestry. (
  • Analysis of the mechanism underlying a mild phenotype of hereditary coproporphyria due to a homozygous missense mutation in the transcription initiation codon of the coproporphyrinogen III oxidase gene. (
  • However, with early diagnosis of active disease, identification of asymptomatic protoporphyrinogen oxidase gene mutation carriers, and avoidance of drugs and other factors known to induce or worsen clinical expression, symptomatology among those at risk can be minimized. (
  • As only patients with mutation in this region (K404E) would develop harderoporphyria, this mutation led to diminishment of the second step of the decarboxylation reaction during the conversion of coproporphyrinogen to protoporphyrinogen, implying that the active site of the enzyme involved in the second step of decarboxylation is located in exon 6. (
  • Coproporphyrinogen oxidase (CPO) is an essential enzyme that catalyzes the sixth step of the heme biosynthetic pathway. (
  • Hereditary coproporphyria (HCP) is a form of hepatic porphyria associated with a deficiency of the enzyme coproporphyrinogen III oxidase. (
  • Inheritance of two mutant protoporphyrin oxidase genes causes a more profound reduction in residual enzyme activity to 25% or less, leading to more severe disease manifestations. (
  • The Escherichia coli Protein YfeX Functions as a Porphyrinogen Oxidase, Not a Heme Dechelatase. (
  • Lead causes a decrease in heme synthesis by inhibiting Delta-aminolevulinic acid (delta-ALA) dehydratase, ferrochelatase, and the coproporphyrinogen oxidase pathway. (
  • Protoporphyrinogen IX is converted to protoporphyrin IX by protoporphyrinogen oxidase. (
  • DE Oxygen-dependent coproporphyrinogen-III oxidase [hemF]. (
  • Very rare childhood cases have been ascribed to the presence of 2 mutant protoporphyrinogen oxidase genes in the same individual. (
  • The last three enzymes of the pathway, namely, coproporphyrinogen III oxidase, protoporphyrinogen oxidase, and ferrochelatase, are also located within mitochondria, whereas the 2nd-5th enzymes are found in the cytoplasm or soluble fraction of the cell. (
  • Cause is partial defect in coproporphyrin oxidase with deficient conversion of coproporphyrinogen-9. (
  • Substrate specificity of catechol oxidase from Lycopus europaeus and characterization of the bioproducts of enzymic caffeic acid oxidation. (
  • The substrate specificity of catechol oxidase from Lycopus europaeus towards phenols is examined. (
  • [ 2 ] In patients with coproporphyria, the function of coproporphyrinogen oxidase is only 40-60% of normal. (
  • In vitro metabolism of citalopram by monoamine oxidase B in human blood. (
  • It is caused due to the deficiency of the enzyme coproporphyrinogen oxidase. (
  • The enzyme catalyzes the step-wise oxidative decarboxylation of the heme precursor, coproporphyrinogen III, to protoporphyrinogen IX via a tricarboxylic intermediate, harderoporphyrinogen. (
  • During heme biosynthesis the oxygen-independent coproporphyrinogen III oxidase HemN catalyzes the oxidative decarboxylation of the two propionate side chains on rings A and B of coproporphyrinogen III to the corresponding vinyl groups to yield protoporphyrinogen IX. (
  • This enzyme catalyzes the stepwise oxidative decarboxylation of coproporphyrinogen III to protoporphyrinogen IX, a precursor of heme. (
  • As only patients with mutation in this region (K404E) would develop harderoporphyria, this mutation led to diminishment of the second step of the decarboxylation reaction during the conversion of coproporphyrinogen to protoporphyrinogen, implying that the active site of the enzyme involved in the second step of decarboxylation is located in exon 6. (
  • It is caused by the deficiency of protoporphyrinogen oxidase. (
  • Protoporphyrinogen oxidase then catalyzes the oxygen-dependent aromatization of protoporphyrinogen into protoporphyrin. (
  • Variegate porphyria (also porphyria variegata or mixed porphyria ) results from a partial deficiency in PROTO oxidase, manifesting itself with skin lesions similar to those of porphyria cutanea tarda combined with acute neurologic attacks. (
  • An enzyme that catalyzes the oxidative decarboxylation of coproporphyrinogen III to protoporphyrinogen IX by the conversion of two propionate groups to two vinyl groups. (
  • Catalyzes the aerobic oxidative decarboxylation of propionate groups of rings A and B of coproporphyrinogen-III to yield the vinyl groups in protoporphyrinogen-IX. (
  • The next step is the oxidative decarboxylation of the propionate side chains on the ring A and B of coproporphyrinogen molecule to yield protoporphyrinogen IX. (
  • Simultaneously, steady-state levels of coproporphyrinogen oxidase mRNA increased but aminolaevulinic acid dehydratase mRNA levels remained unchanged. (
  • Modification of neurobehavioral effects of mercury by a genetic polymorphism of coproporphyrinogen oxidase in children. (
  • Inheritance of two mutant protoporphyrin oxidase genes causes a more profound reduction in residual enzyme activity to 25% or less, leading to more severe disease manifestations. (

No images available that match "coproporphyrinogen oxidase"