I.2 Photosynthesis, the conditions necessary for it. Dark phase of photosynthesis What is nadph in biology

- synthesis of organic substances from carbon dioxide and water with the obligatory use of light energy:

6CO 2 + 6H 2 O + Q light → C 6 H 12 O 6 + 6O 2.

In higher plants, the organ of photosynthesis is the leaf, and the organelles of photosynthesis are the chloroplasts (structure of chloroplasts - lecture No. 7). The membranes of chloroplast thylakoids contain photosynthetic pigments: chlorophylls and carotenoids. There are several different types of chlorophyll ( a, b, c, d), the main one is chlorophyll a. In the chlorophyll molecule, a porphyrin “head” with a magnesium atom in the center and a phytol “tail” can be distinguished. The porphyrin “head” is a flat structure, is hydrophilic and therefore lies on the surface of the membrane that faces the aqueous environment of the stroma. The phytol “tail” is hydrophobic and due to this retains the chlorophyll molecule in the membrane.

Chlorophylls absorb red and blue-violet light, reflect green light and therefore give plants their characteristic green color. Chlorophyll molecules in thylakoid membranes are organized into photosystems. Plants and blue-green algae have photosystem-1 and photosystem-2, while photosynthetic bacteria have photosystem-1. Only photosystem-2 can decompose water to release oxygen and take electrons from the hydrogen of water.

Photosynthesis is a complex multi-step process; photosynthesis reactions are divided into two groups: reactions light phase and reactions dark phase.

Light phase

This phase occurs only in the presence of light in thylakoid membranes with the participation of chlorophyll, electron transport proteins and the enzyme ATP synthetase. Under the influence of a quantum of light, chlorophyll electrons are excited, leave the molecule and enter the outer side of the thylakoid membrane, which ultimately becomes negatively charged. Oxidized chlorophyll molecules are reduced, taking electrons from water located in the intrathylakoid space. This leads to the breakdown or photolysis of water:

H 2 O + Q light → H + + OH - .

Hydroxyl ions give up their electrons, becoming reactive radicals.OH:

OH - → .OH + e - .

OH radicals combine to form water and free oxygen:

4NO. → 2H 2 O + O 2.

In this case, oxygen is removed to the external environment, and protons accumulate inside the thylakoid in the “proton reservoir”. As a result, the thylakoid membrane, on the one hand, is charged positively due to H +, and on the other, due to electrons, it is charged negatively. When the potential difference between the outer and inner sides of the thylakoid membrane reaches 200 mV, protons are pushed through the ATP synthetase channels and ADP is phosphorylated to ATP; Atomic hydrogen is used to restore the specific carrier NADP + (nicotinamide adenine dinucleotide phosphate) to NADPH 2:

2H + + 2e - + NADP → NADPH 2.

Thus, in the light phase, photolysis of water occurs, which is accompanied by three important processes: 1) ATP synthesis; 2) the formation of NADPH 2; 3) the formation of oxygen. Oxygen diffuses into the atmosphere, ATP and NADPH 2 are transported into the stroma of the chloroplast and participate in the processes of the dark phase.

1 - chloroplast stroma; 2 - grana thylakoid.

Dark phase

This phase occurs in the stroma of the chloroplast. Its reactions do not require light energy, so they occur not only in the light, but also in the dark. Dark phase reactions are a chain of successive transformations of carbon dioxide (coming from the air), leading to the formation of glucose and other organic substances.

The first reaction in this chain is the fixation of carbon dioxide; The carbon dioxide acceptor is a five-carbon sugar. ribulose biphosphate(RiBF); enzyme catalyzes the reaction Ribulose biphosphate carboxylase(RiBP carboxylase). As a result of carboxylation of ribulose bisphosphate, an unstable six-carbon compound is formed, which immediately breaks down into two molecules phosphoglyceric acid(FGK). A cycle of reactions then occurs in which phosphoglyceric acid is converted through a series of intermediates to glucose. These reactions use the energy of ATP and NADPH 2 formed in the light phase; The cycle of these reactions is called the “Calvin cycle”:

6CO 2 + 24H + + ATP → C 6 H 12 O 6 + 6H 2 O.

In addition to glucose, other monomers of complex organic compounds are formed during photosynthesis - amino acids, glycerol and fatty acids, nucleotides. Currently, there are two types of photosynthesis: C 3 - and C 4 photosynthesis.

C 3-photosynthesis

This is a type of photosynthesis in which the first product is three-carbon (C3) compounds. C 3 photosynthesis was discovered before C 4 photosynthesis (M. Calvin). It is C 3 photosynthesis that is described above, under the heading “Dark phase”. Characteristic features of C 3 photosynthesis: 1) the carbon dioxide acceptor is RiBP, 2) the carboxylation reaction of RiBP is catalyzed by RiBP carboxylase, 3) as a result of carboxylation of RiBP, a six-carbon compound is formed, which decomposes into two PGAs. FGK is restored to triose phosphates(TF). Some of the TF is used for the regeneration of RiBP, and some is converted into glucose.

1 - chloroplast; 2 - peroxisome; 3 - mitochondria.

This is a light-dependent absorption of oxygen and release of carbon dioxide. At the beginning of the last century, it was established that oxygen suppresses photosynthesis. As it turned out, for RiBP carboxylase the substrate can be not only carbon dioxide, but also oxygen:

O 2 + RiBP → phosphoglycolate (2C) + PGA (3C).

The enzyme is called RiBP oxygenase. Oxygen is a competitive inhibitor of carbon dioxide fixation. The phosphate group is split off and the phosphoglycolate becomes glycolate, which the plant must utilize. It enters peroxisomes, where it is oxidized to glycine. Glycine enters the mitochondria, where it is oxidized to serine, with the loss of already fixed carbon in the form of CO 2. As a result, two glycolate molecules (2C + 2C) are converted into one PGA (3C) and CO 2. Photorespiration leads to a decrease in the yield of C3 plants by 30-40% ( With 3 plants- plants characterized by C 3 photosynthesis).

C 4 photosynthesis is photosynthesis in which the first product is four-carbon (C 4) compounds. In 1965, it was found that in some plants (sugar cane, corn, sorghum, millet) the first products of photosynthesis are four-carbon acids. These plants were called With 4 plants. In 1966, Australian scientists Hatch and Slack showed that C4 plants have virtually no photorespiration and absorb carbon dioxide much more efficiently. The pathway of carbon transformations in C 4 plants began to be called by Hatch-Slack.

C 4 plants are characterized by a special anatomical structure of the leaf. All vascular bundles are surrounded by a double layer of cells: the outer layer is mesophyll cells, the inner layer is sheath cells. Carbon dioxide is fixed in the cytoplasm of mesophyll cells, the acceptor is phosphoenolpyruvate(PEP, 3C), as a result of carboxylation of PEP, oxaloacetate (4C) is formed. The process is catalyzed PEP carboxylase. Unlike RiBP carboxylase, PEP carboxylase has a greater affinity for CO 2 and, most importantly, does not interact with O 2 . Mesophyll chloroplasts have many grains where light phase reactions actively occur. Dark phase reactions occur in the chloroplasts of the sheath cells.

Oxaloacetate (4C) is converted to malate, which is transported through plasmodesmata into the sheath cells. Here it is decarboxylated and dehydrogenated to form pyruvate, CO 2 and NADPH 2 .

Pyruvate returns to the mesophyll cells and is regenerated using the energy of ATP in PEP. CO 2 is again fixed by RiBP carboxylase to form PGA. PEP regeneration requires ATP energy, so it requires almost twice as much energy as C 3 photosynthesis.

The meaning of photosynthesis

Thanks to photosynthesis, billions of tons of carbon dioxide are absorbed from the atmosphere every year and billions of tons of oxygen are released; photosynthesis is the main source of the formation of organic substances. Oxygen forms the ozone layer, which protects living organisms from short-wave ultraviolet radiation.

During photosynthesis, a green leaf uses only about 1% of the solar energy falling on it; productivity is about 1 g of organic matter per 1 m2 of surface per hour.

Chemosynthesis

The synthesis of organic compounds from carbon dioxide and water, carried out not due to the energy of light, but due to the energy of oxidation of inorganic substances, is called chemosynthesis. Chemosynthetic organisms include some types of bacteria.

Nitrifying bacteria ammonia is oxidized to nitrous and then to nitric acid (NH 3 → HNO 2 → HNO 3).

Iron bacteria convert ferrous iron into oxide iron (Fe 2+ → Fe 3+).

Sulfur bacteria oxidize hydrogen sulfide to sulfur or sulfuric acid (H 2 S + ½O 2 → S + H 2 O, H 2 S + 2O 2 → H 2 SO 4).

As a result of oxidation reactions of inorganic substances, energy is released, which is stored by bacteria in the form of high-energy ATP bonds. ATP is used for the synthesis of organic substances, which proceeds similarly to the reactions of the dark phase of photosynthesis.

Chemosynthetic bacteria contribute to the accumulation of minerals in the soil, improve soil fertility, promote wastewater treatment, etc.

Go to lectures No. 11“The concept of metabolism. Biosynthesis of proteins"

Go to lectures No. 13“Methods of division of eukaryotic cells: mitosis, meiosis, amitosis”

There are three types of plastids:

chloroplasts- green, function - photosynthesis
chromoplasts- red and yellow, are dilapidated chloroplasts, can give bright colors to petals and fruits.
leucoplasts- colorless, function - storage of substances.

The structure of chloroplasts

Covered with two membranes. The outer membrane is smooth, the inner one has outgrowths inward - thylakoids. Stacks of short thylakoids are called grains, they increase the area of the inner membrane in order to accommodate as many photosynthetic enzymes as possible.

The internal environment of the chloroplast is called the stroma. It contains circular DNA and ribosomes, due to which chloroplasts independently make part of their proteins, which is why they are called semi-autonomous organelles. (It is believed that plastids were previously free bacteria that were absorbed by a large cell, but not digested.)

Photosynthesis (simple)

In the green leaves in the light
In chloroplasts using chlorophyll
From carbon dioxide and water
Glucose and oxygen are synthesized.

Photosynthesis (medium difficulty)

1. Light phase.
Occurs in the light in the grana of chloroplasts. Under the influence of light, decomposition (photolysis) of water occurs, producing oxygen, which is released, as well as hydrogen atoms (NADP-H) and ATP energy, which are used in the next stage.

2. Dark phase.
Occurs both in light and in darkness (light is not needed), in the stroma of chloroplasts. From carbon dioxide obtained from the environment and hydrogen atoms obtained in the previous stage, glucose is synthesized using the energy of ATP obtained in the previous stage.

1. Establish a correspondence between the process of photosynthesis and the phase in which it occurs: 1) light, 2) dark. Write numbers 1 and 2 in the correct order.
A) formation of NADP-2H molecules
B) release of oxygen
B) monosaccharide synthesis
D) synthesis of ATP molecules
D) addition of carbon dioxide to carbohydrate

Answer

2. Establish a correspondence between the characteristic and the phase of photosynthesis: 1) light, 2) dark. Write numbers 1 and 2 in the correct order.
A) photolysis of water
B) carbon dioxide fixation
B) splitting of ATP molecules
D) excitation of chlorophyll by light quanta
D) glucose synthesis

Answer

3. Establish a correspondence between the process of photosynthesis and the phase in which it occurs: 1) light, 2) dark. Write numbers 1 and 2 in the correct order.
A) formation of NADP*2H molecules
B) release of oxygen
B) glucose synthesis
D) synthesis of ATP molecules
D) reduction of carbon dioxide

Answer

4. Establish a correspondence between the processes and the phase of photosynthesis: 1) light, 2) dark. Write numbers 1 and 2 in the order corresponding to the letters.
A) polymerization of glucose
B) carbon dioxide binding
B) ATP synthesis
D) photolysis of water
D) formation of hydrogen atoms
E) glucose synthesis

Answer

5. Establish a correspondence between the phases of photosynthesis and their characteristics: 1) light, 2) dark. Write numbers 1 and 2 in the order corresponding to the letters.
A) photolysis of water occurs
B) ATP is formed
B) oxygen is released into the atmosphere
D) proceeds with the expenditure of ATP energy
D) reactions can occur both in light and in darkness

Answer

6 Sat. Establish a correspondence between the phases of photosynthesis and their characteristics: 1) light, 2) dark. Write numbers 1 and 2 in the order corresponding to the letters.
A) restoration of NADP+
B) transport of hydrogen ions across the membrane
B) occurs in the grana of chloroplasts
D) carbohydrate molecules are synthesized
D) chlorophyll electrons move to a higher energy level
E) ATP energy is consumed

Answer

FORMING 7:
A) movement of excited electrons
B) conversion of NADP-2R to NADP+

Analyze the table. Fill in the blank cells of the table using the concepts and terms given in the list. For each lettered cell, select the appropriate term from the list provided.
1) thylakoid membranes
2) light phase
3) fixation of inorganic carbon
4) photosynthesis of water
5) dark phase
6) cell cytoplasm

Answer

Analyze the table “Reactions of Photosynthesis”. For each letter, select the corresponding term from the list provided.
1) oxidative phosphorylation
2) oxidation of NADP-2H
3) thylakoid membranes
4) glycolysis
5) addition of carbon dioxide to pentose
6) oxygen formation
7) formation of ribulose diphosphate and glucose
8) synthesis of 38 ATP

Answer

Choose three options. The dark phase of photosynthesis is characterized by
1) the occurrence of processes on the internal membranes of chloroplasts
2) glucose synthesis
3) fixation of carbon dioxide
4) the course of processes in the stroma of chloroplasts
5) the presence of photolysis of water
6) ATP formation

Answer

1. The features listed below, except two, are used to describe the structure and functions of the cell organelle depicted. Identify two characteristics that “fall out” from the general list and write down the numbers under which they are indicated.

2) accumulates ATP molecules
3) provides photosynthesis

5) has semi-autonomy

Answer

2. All of the characteristics listed below, except two, can be used to describe the cell organelle shown in the figure. Identify two characteristics that “drop out” from the general list and write down the numbers under which they are indicated.
1) single-membrane organelle
2) consists of cristae and chromatin
3) contains circular DNA
4) synthesizes its own protein
5) capable of division

Answer

All of the following characteristics, except two, can be used to describe the structure and functions of the chloroplast. Identify two characteristics that “drop out” from the general list and write down the numbers under which they are indicated.
1) is a double-membrane organelle
2) has its own closed DNA molecule
3) is a semi-autonomous organelle
4) forms the spindle
5) filled with cell sap with sucrose

Answer

Choose one, the most correct option. Cellular organelle containing a DNA molecule
1) ribosome
2) chloroplast
3) cell center
4) Golgi complex

Answer

Choose one, the most correct option. In the synthesis of what substance do hydrogen atoms participate in the dark phase of photosynthesis?
1) NADP-2H
2) glucose
3) ATP
4) water

Answer

All of the following characteristics, except two, can be used to determine the processes of the light phase of photosynthesis. Identify two characteristics that “drop out” from the general list and write down the numbers under which they are indicated.
1) photolysis of water

4) formation of molecular oxygen

Answer

Choose two correct answers out of five and write down the numbers under which they are indicated. During the light phase of photosynthesis in the cell
1) oxygen is formed as a result of the decomposition of water molecules
2) carbohydrates are synthesized from carbon dioxide and water
3) polymerization of glucose molecules occurs to form starch
4) ATP molecules are synthesized
5) the energy of ATP molecules is spent on the synthesis of carbohydrates

Answer

Choose one, the most correct option. Which cellular organelle contains DNA?
1) vacuole
2) ribosome
3) chloroplast
4) lysosome

Answer

Insert into the text “Synthesis of organic substances in a plant” the missing terms from the proposed list, using numerical notations. Write down the selected numbers in the order corresponding to the letters. Plants store the energy necessary for their existence in the form of organic substances. These substances are synthesized during __________ (A). This process occurs in leaf cells in __________ (B) - special green plastids. They contain a special green substance – __________ (B). A prerequisite for the formation of organic substances in addition to water and carbon dioxide is __________ (D).
List of terms:
1) breathing
2) evaporation
3) leukoplast
4) food
5) light
6) photosynthesis
7) chloroplast
8) chlorophyll

Answer

Choose one, the most correct option. In cells, primary glucose synthesis occurs in
1) mitochondria
2) endoplasmic reticulum
3) Golgi complex
4) chloroplasts

Answer

Choose one, the most correct option. Oxygen molecules during photosynthesis are formed due to the decomposition of molecules
1) carbon dioxide
2) glucose
3) ATP
4) water

Answer

Choose one, the most correct option. Are the following statements about photosynthesis correct? A) In the light phase, the energy of light is converted into the energy of chemical bonds of glucose. B) Dark phase reactions occur on thylakoid membranes, into which carbon dioxide molecules enter.
1) only A is correct
2) only B is correct
3) both judgments are correct
4) both judgments are incorrect

Answer

1. Establish the correct sequence of processes occurring during photosynthesis. Write down the numbers under which they are indicated in the table.
1) Use of carbon dioxide
2) Oxygen formation
3) Carbohydrate synthesis
4) Synthesis of ATP molecules
5) Excitation of chlorophyll

Answer

2. Establish the correct sequence of photosynthesis processes.
1) conversion of solar energy into ATP energy
2) formation of excited electrons of chlorophyll
3) carbon dioxide fixation
4) formation of starch
5) conversion of ATP energy into glucose energy

Answer

3. Establish the sequence of processes occurring during photosynthesis. Write down the corresponding sequence of numbers.

2) ATP breakdown and energy release
3) glucose synthesis
4) synthesis of ATP molecules
5) stimulation of chlorophyll

Answer

Select three features of the structure and functions of chloroplasts
1) internal membranes form cristae
2) many reactions occur in grains
3) glucose synthesis occurs in them
4) are the site of lipid synthesis
5) consist of two different particles
6) double-membrane organelles

Answer

Identify three true statements from the general list, and write down the numbers under which they are indicated in the table. During the light phase of photosynthesis occurs
1) photolysis of water
2) reduction of carbon dioxide to glucose
3) synthesis of ATP molecules using the energy of sunlight
4) hydrogen connection with the NADP+ transporter
5) use of the energy of ATP molecules for the synthesis of carbohydrates

Answer

All but two of the characteristics listed below can be used to describe the light phase of photosynthesis. Identify two characteristics that “drop out” from the general list and write down the numbers under which they are indicated.
1) a by-product is formed - oxygen
2) occurs in the stroma of the chloroplast
3) binding of carbon dioxide
4) ATP synthesis
5) photolysis of water

Answer

Choose one, the most correct option. The process of photosynthesis should be considered as one of the important links in the carbon cycle in the biosphere, since during its
1) plants absorb carbon from inanimate nature into living matter
2) plants release oxygen into the atmosphere
3) organisms release carbon dioxide during respiration
4) industrial production replenishes the atmosphere with carbon dioxide

Answer

Establish a correspondence between the stages of the process and the processes: 1) photosynthesis, 2) protein biosynthesis. Write numbers 1 and 2 in the correct order.
A) release of free oxygen
B) formation of peptide bonds between amino acids
B) synthesis of mRNA on DNA
D) translation process
D) restoration of carbohydrates
E) conversion of NADP+ to NADP 2H

Answer

Select cell organelles and their structures involved in the process of photosynthesis.
1) lysosomes
2) chloroplasts
3) thylakoids
4) grains
5) vacuoles
6) ribosomes

Answer

The following terms, except two, are used to describe plastids. Identify two terms that “drop out” from the general list and write down the numbers under which they are indicated in the table.
1) pigment
2) glycocalyx
3) grana
4) crista
5) thylakoid

Answer

All but two of the following characteristics can be used to describe the process of photosynthesis. Identify two characteristics that “drop out” from the general list, and write down the numbers under which they are indicated in your answer.
1) Light energy is used to carry out the process.
2) The process occurs in the presence of enzymes.
3) The central role in the process belongs to the chlorophyll molecule.
4) The process is accompanied by the breakdown of the glucose molecule.
5) The process cannot occur in prokaryotic cells.

Answer

The following concepts, except two, are used to describe the dark phase of photosynthesis. Identify two concepts that “fall out” from the general list and write down the numbers under which they are indicated.
1) carbon dioxide fixation
2) photolysis
3) oxidation of NADP 2H
4) grana
5) stroma

Answer

The features listed below, except two, are used to describe the structure and functions of the cell organelle depicted. Identify two characteristics that “fall out” from the general list and write down the numbers under which they are indicated.
1) breaks down biopolymers into monomers
2) accumulates ATP molecules
3) provides photosynthesis
4) refers to double-membrane organelles
5) has semi-autonomy

Answer

Establish a correspondence between the processes and their localization in chloroplasts: 1) stroma, 2) thylakoid. Write numbers 1 and 2 in the order corresponding to the letters.
A) use of ATP
B) photolysis of water
B) stimulation of chlorophyll
D) formation of pentose
D) electron transfer along the enzyme chain

Answer

As the name implies, photosynthesis is essentially the natural synthesis of organic substances, converting CO2 from the atmosphere and water into glucose and free oxygen.

This requires the presence of solar energy.

The chemical equation for the process of photosynthesis can generally be represented as follows:

Photosynthesis has two phases: dark and light. The chemical reactions of the dark phase of photosynthesis differ significantly from the reactions of the light phase, but the dark and light phases of photosynthesis depend on each other.

The light phase can occur in plant leaves exclusively in sunlight. For dark, the presence of carbon dioxide is necessary, which is why the plant must constantly absorb it from the atmosphere. All comparative characteristics of the dark and light phases of photosynthesis will be provided below. For this purpose, a comparative table “Phases of Photosynthesis” was created.

Light phase of photosynthesis

The main processes in the light phase of photosynthesis occur in the thylakoid membranes. It involves chlorophyll, electron transport proteins, ATP synthetase (an enzyme that accelerates the reaction) and sunlight.

Further, the reaction mechanism can be described as follows: when sunlight hits the green leaves of plants, chlorophyll electrons (negative charge) are excited in their structure, which, having passed into an active state, leave the pigment molecule and end up on the outside of the thylakoid, the membrane of which is also negatively charged. At the same time, chlorophyll molecules are oxidized and the already oxidized ones are reduced, thus taking electrons from the water that is in the leaf structure.

This process leads to the fact that water molecules disintegrate, and the ions created as a result of photolysis of water give up their electrons and turn into OH radicals that are capable of carrying out further reactions. These reactive OH radicals then combine to create full-fledged water molecules and oxygen. In this case, free oxygen escapes into the external environment.

As a result of all these reactions and transformations, the leaf thylakoid membrane on one side is charged positively (due to the H+ ion), and on the other - negatively (due to electrons). When the difference between these charges on the two sides of the membrane reaches more than 200 mV, protons pass through special channels of the ATP synthetase enzyme and due to this, ADP is converted to ATP (as a result of the phosphorylation process). And atomic hydrogen, which is released from water, restores the specific carrier NADP+ to NADP·H2. As we can see, as a result of the light phase of photosynthesis, three main processes occur:

ATP synthesis;
creation of NADP H2;
formation of free oxygen.

The latter is released into the atmosphere, and NADP H2 and ATP take part in the dark phase of photosynthesis.

Dark phase of photosynthesis

The dark and light phases of photosynthesis are characterized by large energy expenditures on the part of the plant, but the dark phase proceeds faster and requires less energy. Dark phase reactions do not require sunlight, so they can occur both day and night.

All the main processes of this phase occur in the stroma of the plant chloroplast and represent a unique chain of successive transformations of carbon dioxide from the atmosphere. The first reaction in such a chain is the fixation of carbon dioxide. To make it happen more smoothly and faster, nature provided the enzyme RiBP-carboxylase, which catalyzes the fixation of CO2.

Next, a whole cycle of reactions occurs, the completion of which is the conversion of phosphoglyceric acid into glucose (natural sugar). All these reactions use the energy of ATP and NADP H2, which were created in the light phase of photosynthesis. In addition to glucose, photosynthesis also produces other substances. Among them are various amino acids, fatty acids, glycerol, and nucleotides.

Phases of photosynthesis: comparison table

*Comparison criteria*	*Light phase*	*Dark phase*
sunlight	Required	Not required
Place of reaction	Chloroplast grana	Chloroplast stroma
Dependency on energy source	Depends on sunlight	Depends on ATP and NADP H2 formed in the light phase and on the amount of CO2 from the atmosphere
Starting materials	Chlorophyll, electron transport proteins, ATP synthetase	Carbon dioxide
The essence of the phase and what is formed	Free O2 is released, ATP and NADP H2 are formed	Formation of natural sugar (glucose) and absorption of CO2 from the atmosphere

Photosynthesis - video

NADH - the basis of energy and life

In its ordinary sense, biological life can be defined as the ability to generate energy within a cell. This energy is high-energy phosphate bonds of chemicals synthesized in the body. The most important high-energy compounds are adenosine triphosphate (ATP), guanosine triphosphate (GTP), creatine phosphoric acid, nicotinamide dinucleotide phosphate (NAD(H) and NADP(H)), phosphorylated carbohydrates.

Nicotinamide adenine dinucleotide (NADH) is a coenzyme present in all living cells and is part of the dehydrogenase group of enzymes that catalyze redox reactions; performs the function of a carrier of electrons and hydrogen, which it receives from oxidizable substances. The reduced form (NADH) is capable of transferring them to other substances.

How to improve performance

What is NADH? Many people call it “an abbreviation for life.” And indeed it is. NADH (nicotinamide adenine dinucleotide coenzyme) is found in all living cells and is a vital element through which energy is produced inside cells. NADH is involved in the production of ATP (ATP). NAD(H), as a universal energy molecule, unlike ATP, can constantly unload mitochondria from excessive accumulation of lactate towards the formation of pyruvate from it, due to stimulation of the pyruvate dehydrogenase complex, which is sensitive specifically to the NAD(H)/NAD ratio.

Chronic Fatigue Syndrome: Focus on Mitochondria

A number of clinical studies have shown the effectiveness of NADH drugs in CFS. The daily dose was usually 50 mg. The most powerful effect occurred after 2-4 weeks of treatment. Fatigue decreased by 37-52%. In addition, such an objective cognitive parameter as concentration of attention improved.

NADH in the treatment of chronic fatigue syndrome

NADH (vitamin B3 coenzyme), present in all living cells, is part of the dehydrogenase group of enzymes that catalyze redox reactions; performs the function of a carrier of electrons and hydrogen, which it receives from oxidizable substances. It is a reserve source of energy in cells. It takes part in almost all energy production reactions, ensuring cell respiration. By influencing the corresponding processes in the brain, the vitamin B3 coenzyme can prevent the death of nerve cells during hypoxia or age-related changes. Takes part in detoxification processes in the liver. Recently, its ability to block lactate dehydrogenase and, thereby, limit ischemic and/or hypoxic damage to the myocardium has been established. Studies of the effectiveness of oral administration in the treatment of chronic fatigue syndrome have confirmed its activating effect on people’s condition.

NADH in sports and medicine: review of foreign literature

We wrote about NADH (nicotinamide adenine dinucleotide phosphate) in previous articles. Now we want to provide information from English-language sources about the role and significance of this substance in energy metabolism in the body, its effect on the nervous system, and its role in the development of a number of pathological situations and prospects for use in medicine and sports. (Download monograph on NADH).

Herbalife Quickspark CoEnzyme 1 (NADH) ATP Energy

Natural Energy at a Cellular Level

Quickspark is a product of the company Herbalife. It is a stable form of Vitamin B3 CoEnzyme1. CoEnzyme1 was found in 1906 in Austria by a scientist called Professor George Birkmayer. CoEnzyme1 was developed for medical purposes and used in the second world war.

NADH (Enada)

Nicotinamide adenine dinucleotide (NADH) is a substance that helps the functionality of enzymes in the body. NADH plays a role in the production of energy and helps produce L-dopa, which the body turns into the neurotransmitter dopamine. NADH is being evaluated for many conditions and may be helpful for enhancing mental functionality and memory.

Enzymes, like proteins, are divided into 2 groups: simple And complex. Simple ones consist entirely of amino acids and, upon hydrolysis, form exclusively amino acids. Their spatial organization is limited by the tertiary structure. These are mainly gastrointestinal enzymes: pepsin, trypsin, lysacym, phosphatase. Complex enzymes, in addition to the protein part, also contain non-protein components. These non-protein components differ in the strength of binding to the protein part (alloenzyme). If the dissociation constant of a complex enzyme is so small that in solution all polypeptide chains are associated with their non-protein components and are not separated during isolation and purification, then the non-protein component is called prosthetic group and is considered as an integral part of the enzyme molecule.

Under coenzyme understand an additional group that is easily separated from the alloenzyme upon dissociation. There is a rather complex covalent bond between the alloenzyme and the simplest group. There is a non-covalent bond (hydrogen or electrostatic interactions) between the alloenzyme and the coenzyme. Typical representatives of coenzymes are:

B 1 - thiamine; pyrophosphate (it contains B)

B 2 - riboflavin; FAD, FNK

PP - NAD, NADP

H – biotin; biositine

B 6 - pyridoxine; pyridoxal phosphate

Pantothenic acid: coenzyme A

Many divalent metals (Cu, Fe, Mn, Mg) also act as cofactors, although they are neither coenzymes nor prosthetic groups. Metals are part of the active center or stabilize the optimal structure of the active center.

METALSENZYMES

Fe, Fehemoglobin, catalase, peroxidase

Cu,Cu cytochrome oxidase

ZnDNA – polymerase, dehydrogenase

Mghexokinase

Mnarginase

Seglutathione reductase

ATP, lactic acid, and tRNA can also perform a cofactor function. One distinctive feature of two-component enzymes should be noted, which is that neither the cofactor (coenzyme or prosthetic group) nor the alloenzyme individually exhibit catalytic activity, and only their integration into a single whole, proceeding in accordance with the program of their three-dimensional organization, ensures rapid the occurrence of chemical reactions.

Structure of NAD and NADP.

NAD and NADP are coenzymes of pyridine-dependent dehydrogenases.

NICOTINAMIDE ADNINE DINE NUCLEOTIDE.

NICOTINAMIDE ADNINE DINE NUCLEOAMIDE PHOSPHATE (NADP)

The ability of NAD and NADP to play the role of an accurate hydrogen carrier is associated with the presence in their structure -

nicotinic acid reamide.

In cells, NAD-dependent dehydrogenases are involved

in the processes of electron transfer from the substrate to O.

NADP-dependent dehydrogenases play a role in the process -

sah biosynthesis. Therefore, the coenzymes NAD and NADP

differ in intracellular localization: NAD

concentrated in mitochondria, and most of the NADP

is located in the cytoplasm.

Structure of FAD and FMN.

FAD and FMN are prosthetic groups of flavin enzymes. They are very firmly attached to the alloenzyme, unlike NAD and NADP.

FLAVIN MONONUCLEOTIDE (FMN).

FLAVINACETYLDINUCLEOTIDE.

The active part of the FAD and FMN molecule is the isoalloxadine ring riboflavin, to the nitrogen atoms of which 2 hydrogen atoms can be attached.