A report on Cofactor (biochemistry)

The succinate dehydrogenase complex showing several cofactors, including flavin, iron–sulfur centers, and heme.
A simple [Fe2S2] cluster containing two iron atoms and two sulfur atoms, coordinated by four protein cysteine residues.
The redox reactions of nicotinamide adenine dinucleotide.

Non-protein chemical compound or metallic ion that is required for an enzyme's role as a catalyst .

- Cofactor (biochemistry)
The succinate dehydrogenase complex showing several cofactors, including flavin, iron–sulfur centers, and heme.

45 related topics with Alpha

Overall

This nucleotide contains the five-carbon sugar deoxyribose (at center), a nucleobase called adenine (upper right), and one phosphate group (left). The deoxyribose sugar joined only to the nitrogenous base forms a <u title="Nucleotide">Deoxyribonucleoside called deoxyadenosine, whereas the whole structure along with the phosphate group is a <u title="Deoxyadenosine monophosphate" href="deoxyadenosine monophosphate">nucleotide, a constituent of DNA with the name deoxyadenosine monophosphate.

Nucleotide

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Nucleotides are organic molecules consisting of a nucleoside and a phosphate.

Nucleotides are organic molecules consisting of a nucleoside and a phosphate.

This nucleotide contains the five-carbon sugar deoxyribose (at center), a nucleobase called adenine (upper right), and one phosphate group (left). The deoxyribose sugar joined only to the nitrogenous base forms a <u title="Nucleotide">Deoxyribonucleoside called deoxyadenosine, whereas the whole structure along with the phosphate group is a <u title="Deoxyadenosine monophosphate" href="deoxyadenosine monophosphate">nucleotide, a constituent of DNA with the name deoxyadenosine monophosphate.
Showing the arrangement of nucleotides within the structure of nucleic acids: At lower left, a monophosphate nucleotide; its nitrogenous base represents one side of a base-pair. At the upper right, four nucleotides form two base-pairs: thymine and adenine (connected by double hydrogen bonds) and guanine and cytosine (connected by triple hydrogen bonds). The individual nucleotide monomers are chain-joined at their sugar and phosphate molecules, forming two 'backbones' (a double helix) of nucleic acid, shown at upper left.
Structural elements of three nucleo tides —where one-, two- or three-phosphates are attached to the nucleo side (in yellow, blue, green) at center: 1st, the nucleotide termed as a nucleoside mono phosphate is formed by adding a phosphate (in red); 2nd, adding a second phosphate forms a nucleoside di phosphate; 3rd, adding a third phosphate results in a nucleoside tri phosphate. + The nitrogenous base (nucleobase) is indicated by "Base" and "glycosidic bond" (sugar bond). All five primary, or canonical, bases—the purines and pyrimidines—are sketched at right (in blue).
The synthesis of UMP. The color scheme is as follows: enzymes, <span style="color: rgb(219,155,36);">coenzymes, <span style="color: rgb(151,149,45);">substrate names , <span style="color: rgb(128,0,0);">inorganic molecules
The synthesis of IMP. The color scheme is as follows: enzymes, <span style="color: rgb(219,155,36);">coenzymes, <span style="color: rgb(151,149,45);">substrate names , <span style="color: rgb(227,13,196);">metal ions , <span style="color: rgb(128,0,0);">inorganic molecules

They provide chemical energy—in the form of the nucleoside triphosphates, adenosine triphosphate (ATP), guanosine triphosphate (GTP), cytidine triphosphate (CTP) and uridine triphosphate (UTP)—throughout the cell for the many cellular functions that demand energy, including: amino acid, protein and cell membrane synthesis, moving the cell and cell parts (both internally and intercellularly), cell division, etc. In addition, nucleotides participate in cell signaling (cyclic guanosine monophosphate or cGMP and cyclic adenosine monophosphate or cAMP), and are incorporated into important cofactors of enzymatic reactions (e.g. coenzyme A, FAD, FMN, NAD, and NADP+).

Chemical structure

Riboflavin

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Vitamin found in food and sold as a dietary supplement.

Vitamin found in food and sold as a dietary supplement.

Chemical structure
Cultures of Micrococcus luteus growing on pyridine (left) and succinic acid (right). The pyridine culture has turned yellow from the accumulation of riboflavin.

It is essential to the formation of two major coenzymes, flavin mononucleotide and flavin adenine dinucleotide.

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Pyruvate dehydrogenase

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Enzyme that catalyzes the reaction of pyruvate and a lipoamide to give the acetylated dihydrolipoamide and carbon dioxide.

Enzyme that catalyzes the reaction of pyruvate and a lipoamide to give the acetylated dihydrolipoamide and carbon dioxide.

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Simplified mechanism for pyruvate dehydrogenase reaction. The TPP coenzyme is shown with abbreviated substituents.
Pyruvate dehydrogenase E1 subunit of E. coli. Colors represent different chains. Structure determined by Arjunan et al. Biochemistry 2002.  Created with PyMol.
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The conversion requires the coenzyme thiamine pyrophosphate.

A block of electrolytically refined cobalt (99.9% purity) cut from a large plate

Cobalt

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Chemical element with the symbol Co and atomic number 27.

Chemical element with the symbol Co and atomic number 27.

A block of electrolytically refined cobalt (99.9% purity) cut from a large plate
Cobalt(II) chloride hexahydrate
Structure of tetrakis(1-norbornyl)cobalt(IV)
Early Chinese blue and white porcelain, manufactured c. 1335
Cobalt ore
World production trend
Cobalt prices February and March 2021 (USD$ per ton)
Cobalt prices 2016 to 2021 5 years (USD$ per ton)
Cobalt blue glass
Cobalt-colored glass
alt=chemical diagram of cobalamin molecule|Cobalamin
alt=two cobalt-deficient sheep facing away from camera|Cobalt-deficient sheep

Cobalt is the active center of a group of coenzymes called cobalamins.

Vitamin C

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Water-soluble vitamin found in citrus and other fruits and vegetables, and also sold as a dietary supplement.

Water-soluble vitamin found in citrus and other fruits and vegetables, and also sold as a dietary supplement.

Vitamin C supplements at a drug store.
The Nobel prizewinner Linus Pauling advocated taking vitamin C for the common cold in a 1970 book.
Vitamin C biosynthesis in plants
Citrus fruits were among the first sources of vitamin C available to ships' surgeons.
James Lind, a British Royal Navy surgeon who, in 1747, identified that a quality in fruit prevented scurvy in one of the first recorded controlled experiments.
Albert Szent-Györgyi wrote that he won a Nobel Prize after he found a way to mass-produce vitamin C for research purposes when he lived in Szeged, which had become the center of the paprika (red pepper) industry.
Albert Szent-Györgyi, pictured here in 1948, was awarded the 1937 Nobel Prize in Medicine "for his discoveries in connection with the biological combustion processes, with special reference to vitaminC and the catalysis of fumaric acid".

Vitamin C functions as a cofactor in many enzymatic reactions in animals (including humans) that mediate a variety of essential biological functions, including wound healing and collagen synthesis.

Structure of coenzyme A: 1: 3′-phosphoadenosine. 2: diphosphate, organophosphate anhydride. 3: pantoic acid. 4: β-alanine. 5: cysteamine.

Coenzyme A

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Structure of coenzyme A: 1: 3′-phosphoadenosine. 2: diphosphate, organophosphate anhydride. 3: pantoic acid. 4: β-alanine. 5: cysteamine.
Details of the biosynthetic pathway of CoA synthesis from pantothenic acid.
Some of the sources that CoA comes from and uses in the cell.

Coenzyme A (CoA, SHCoA, CoASH) is a coenzyme, notable for its role in the synthesis and oxidation of fatty acids, and the oxidation of pyruvate in the citric acid cycle.

Dihydrofolate reductase from E. coli with its two substrates dihydrofolate (right) and NADPH (left), bound in the active site. The protein is shown as a ribbon diagram, with alpha helices in red, beta sheathes in yellow and loops in blue. Generated from 7DFR.

Enzyme kinetics

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Study of the rates of enzyme-catalysed chemical reactions.

Study of the rates of enzyme-catalysed chemical reactions.

Dihydrofolate reductase from E. coli with its two substrates dihydrofolate (right) and NADPH (left), bound in the active site. The protein is shown as a ribbon diagram, with alpha helices in red, beta sheathes in yellow and loops in blue. Generated from 7DFR.
As larger amounts of substrate are added to a reaction, the available enzyme binding sites become filled to the limit of V_\max. Beyond this limit the enzyme is saturated with substrate and the reaction rate ceases to increase.
Progress curve for an enzyme reaction. The slope in the initial rate period is the initial rate of reaction v. The Michaelis–Menten equation describes how this slope varies with the concentration of substrate.
Lineweaver–Burk or double-reciprocal plot of kinetic data, showing the significance of the axis intercepts and gradient.
Random-order ternary-complex mechanism for an enzyme reaction. The reaction path is shown as a line and enzyme intermediates containing substrates A and B or products P and Q are written below the line.
Saturation curve for an enzyme reaction showing sigmoid kinetics.
Pre-steady state progress curve, showing the burst phase of an enzyme reaction.
Kinetic scheme for reversible enzyme inhibitors.
The energy variation as a function of reaction coordinate shows the stabilisation of the transition state by an enzyme.

These measurements either use changes in the fluorescence of cofactors during an enzyme's reaction mechanism, or of fluorescent dyes added onto specific sites of the protein to report movements that occur during catalysis.

Skeletal formula and ball-and-stick model of the cation in thiamine

Thiamine

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Vitamin, an essential micronutrient, which cannot be made in the body.

Vitamin, an essential micronutrient, which cannot be made in the body.

Skeletal formula and ball-and-stick model of the cation in thiamine
A 3D representation of the TPP riboswitch with thiamine bound
Diamine used in the manufacture of thiamine
Takaki Kanehiro
Christiaan Eijkman
Gerrit Grijns
Umetaro Suzuki
Casimir Funk
Rudolph Peters

Within the body, the best-characterized form is thiamine pyrophosphate (TPP), also called thiamine diphosphate, a coenzyme in the catabolism of sugars and amino acids.

Sodium and fluorine bonding ionically to form sodium fluoride. Sodium loses its outer electron to give it a stable electron configuration, and this electron enters the fluorine atom exothermically. The oppositely charged ions are then attracted to each other. The sodium is oxidized; and the fluorine is reduced.

Redox

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Type of chemical reaction in which the oxidation states of substrate change.

Type of chemical reaction in which the oxidation states of substrate change.

Sodium and fluorine bonding ionically to form sodium fluoride. Sodium loses its outer electron to give it a stable electron configuration, and this electron enters the fluorine atom exothermically. The oppositely charged ions are then attracted to each other. The sodium is oxidized; and the fluorine is reduced.
The international pictogram for oxidizing chemicals
Illustration of a redox reaction
A redox reaction is the force behind an electrochemical cell like the Galvanic cell pictured. The battery is made out of a zinc electrode in a ZnSO4 solution connected with a wire and a porous disk to a copper electrode in a CuSO4 solution.
Oxides, such as iron(III) oxide or rust, which consists of hydrated iron(III) oxides Fe2O3·nH2O and iron(III) oxide-hydroxide (FeO(OH), Fe(OH)3), form when oxygen combines with other elements
Iron rusting in pyrite cubes
Enzymatic browning is an example of a redox reaction that takes place in most fruits and vegetables.
Blast furnaces of Třinec Iron and Steel Works, Czech Republic

In general, the electron donor is any of a wide variety of flavoenzymes and their coenzymes.

Sphalerite (ZnS)

Zinc

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Chemical element with the symbol Zn and atomic number 30.

Chemical element with the symbol Zn and atomic number 30.

Sphalerite (ZnS)
Zinc acetate
Zinc chloride
Late Roman brass bucket – the Hemmoorer Eimer from Warstade, Germany, second to third century AD
Various alchemical symbols for the element zinc
Andreas Sigismund Marggraf is given credit for first isolating pure zinc
Galvanization was named after Luigi Galvani.
Percentage of zinc output in 2006 by countries
World production trend
Zinc Mine Rosh Pinah, Namibia
Zinc Mine Skorpion, Namibia
Hot-dip handrail galvanized crystalline surface
Cast brass microstructure at magnification 400x
Zinc oxide is used as a white pigment in paints.
Addition of diphenylzinc to an aldehyde
GNC zinc 50 mg tablets. The amount exceeds what is deemed the safe upper limit in the United States (40 mg) and European Union (25 mg)
Zinc gluconate is one compound used for the delivery of zinc as a dietary supplement.
Ribbon diagram of human carbonic anhydrase II, with zinc atom visible in the center
Zinc fingers help read DNA sequences.
Foods and spices containing zinc

Enzymes with a zinc atom in the reactive center are widespread in biochemistry, such as alcohol dehydrogenase in humans.