Name: how cells make and use atp
Uploaded: 2025-06-12T09:32:44.000Z
Duration: 1 min 23 s
Channel: JoVE

ATP, was für Adenosintriphosphat steht, dient als Hauptenergietransporter in den Zellen. Es besteht aus einem Adenosinmolekül, das an drei Phosphatgruppen gebunden ist. Diese hochenergetischen Phosphatbindungen speichern Energie, die bei der Hydrolyse freigesetzt wird, und treiben verschiedene zelluläre Prozesse wie Biosynthese, Transport und Bewegung an. Die ATP-Synthese kann über drei Mechanismen erfolgen. Bei der Phosphorylierung auf Substratebene wird eine Phosphatgruppe aus einer hochenergetischen phosphorylierten Verbindung direkt auf ADP übertragen, wodurch ATP erzeugt wird. Die oxidative Phosphorylierung überträgt Elektronen von NADH und FADH2 durch die Elektronentransportkette und erzeugt einen Protonengradienten, der die ATP-Synthese antreibt. Bei der Photophosphorylierung treibt die Lichtenergie Elektronen durch eine Reihe von Elektronenträgern und erzeugt so einen elektrochemischen Gradienten, der für die ATP-Synthese genutzt wird. Die Kopplung der ATP-Synthese mit Oxidations-Reduktions-Reaktionen ist ein grundlegender Aspekt des zellulären Stoffwechsels. ATP wird kontinuierlich hydrolysiert, um Energie für anabole Reaktionen bereitzustellen, und während kataboler Reaktionen regeneriert.

atp und energieproduktion

ATP and Energy Production

Adenosintriphosphat (ATP) ist ein wichtiges Molek&#252;l, das als Hauptenergietr&#228;ger in Zellen fungiert. Strukturell besteht ATP aus Adenosin &#8211; zusammengesetzt aus Adenin und Ribose &#8211; an welches drei Phosphatgruppen gebunden sind. Die energiereichen Bindungen zwischen diesen Phosphatgruppen speichern betr&#228;chtliche Mengen potentieller Energie. Diese Energie wird bei der Hydrolyse freigesetzt, bei der ATP in Adenosindiphosphat (ADP) oder Adenosinmonophosphat (AMP) umgewandelt wird. Dieser Prozess treibt eine Vielzahl essentieller zellul&#228;rer Vorg&#228;nge an, wie etwa die Synthese von Makromolek&#252;len, den intrazellul&#228;ren Transport und mechanische Bewegungen.
Mechanismen der ATP-Synthese
Die ATP-Synthese erfolgt &#252;ber drei prim&#228;re Mechanismen: Substratkettenphosphorylierung, oxidative Phosphorylierung und Photophosphorylierung.
Bei der Substratkettenphosphorylierung wird ATP durch die direkte &#220;bertragung einer Phosphatgruppe von einem energiereichen Zwischenprodukt auf ADP gebildet. Dieser Prozess findet w&#228;hrend der Reaktionen der Glykolyse und des Citratzyklus statt.
Die oxidative Phosphorylierung stellt die ergiebigste Methode der ATP-Erzeugung dar. Dabei werden Elektronen von den Coenzymen NADH und FADH_2 durch die Elektronentransportkette &#252;bertragen. Der Elektronenfluss erzeugt ein Protonengradient entlang der Membran, der von der ATP-Synthase genutzt wird, um ADP und anorganisches Phosphat zu ATP zu verbinden.
Die Photophosphorylierung, ein Prozess, der ausschlie&#223;lich bei photosynthetischen Organismen auftritt, nutzt die Energie von Photonen zur Anregung von Elektronen. Diese durchlaufen eine Reihe von Elektronentransportern in der Thylakoidmembran der Chloroplasten. Der resultierende Protonengradient treibt, &#228;hnlich wie bei der oxidativen Phosphorylierung, die ATP-Bildung an.
ATP als Regulator des Energiestoffwechsels
ATP spielt eine zentrale Rolle im zellul&#228;ren Energiehaushalt, indem es katabole und anabole Reaktionen koppelt. W&#228;hrend kataboler Prozesse, wie der Zellatmung, wird ATP aus ADP und Phosphat regeneriert. Anschlie&#223;end wird es in anabolen Reaktionen hydrolysiert und liefert dabei die Energie, die f&#252;r die Synthese von Biomolek&#252;len erforderlich ist. Dieser kontinuierliche Zyklus aus Hydrolyse und Regeneration von ATP erm&#246;glicht es den Zellen, Energieanforderungen effizient zu steuern, die Hom&#246;ostase aufrechtzuerhalten und lebenswichtige Zellfunktionen zu unterst&#252;tzen.

ATP und Energieproduktion

Adenosintriphosphat (ATP) ist ein wichtiges Molek&#252;l, das als Hauptenergietr&#228;ger in Zellen fungiert. Strukturell besteht ATP aus Adenosin &#8211; ...

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how cells make and use atp

ATP is the main energy carrier in cells. It is made of adenosine, which includes adenine and ribose, plus three phosphate groups. The bonds between the phosphate groups hold a large amount of potential energy. When ATP is hydrolyzed, it becomes ADP or AMP and releases energy for cell work.

Cells use that energy for many essential tasks. It supports macromolecule synthesis, intracellular transport, and mechanical movement. ATP also acts as an energy manager by linking catabolic and anabolic reactions. During catabolic processes such as cellular respiration, ATP is regenerated from ADP and phosphate. During anabolic reactions, ATP hydrolysis provides the energy needed to build biomolecules.

Cells produce ATP in three main ways: substrate-level phosphorylation, oxidative phosphorylation, and photophosphorylation. In substrate-level phosphorylation, a phosphate group moves directly from a high-energy intermediate to ADP. This happens during glycolysis and the citric acid cycle. Oxidative phosphorylation makes the most ATP. It uses electrons from NADH and FADH2 that pass through the electron transport chain. Their movement creates a proton gradient across a membrane, and ATP synthase uses that gradient to join ADP with inorganic phosphate and form ATP.

Photophosphorylation occurs in photosynthetic organisms. It uses light energy to excite electrons, which move through electron carriers in the thylakoid membrane of chloroplasts. The electron flow creates a proton gradient, and that gradient drives ATP production. This process works in a similar way to oxidative phosphorylation. Together, ATP hydrolysis and ATP regeneration help cells meet energy needs and maintain homeostasis.

How Cells Make and Use ATP

microbial nutrition

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atp and energy production

ATP is the main energy carrier in cells. It is made of adenosine, which includes adenine and ribose, plus three phosphate groups. The bonds between the phosphate groups hold a large amount of potential energy. When ATP is hydrolyzed, it becomes ADP or AMP and releases energy for cell work. Cells use that energy for many essential tasks. It supports macromolecule synthesis, intracellular transport, and mechanical movement. ATP also acts as an energy manager by linking catabolic and anabolic...

redox reactions

Electron Carriers in Redox Metabolism

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Metabolism is the set of chemical reactions that keep living cells working. It includes reactions that break down biomolecules and reactions that build them up. These two sides of metabolism work together to support energy balance and cell function. Catabolic pathways break large molecules into smaller parts. Carbohydrates, lipids, and proteins can be broken down into monosaccharides, fatty acids, and amino acids. These reactions release energy, and cells store much of that energy as ATP, or...

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glycolysis

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Glycolysis is a central pathway in glucose catabolism and a major way cells make energy. It is also called the Embden-Meyerhof pathway. This process takes place in the cytoplasm and can work with or without oxygen, which makes it useful in many organisms and conditions. Glycolysis has ten steps and turns one glucose molecule into two pyruvate molecules. It has two phases. In the preparatory phase, the cell uses two ATP to add phosphate groups to glucose and split it into two three-carbon...

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Cellular Respiration: ATP Production Pathways

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Electron Transport Chain Powers ATP Output

The electron transport chain powers ATP production during cellular respiration. It sits in the inner mitochondrial membrane and moves high-energy electrons from NADH and FADH2 to molecular oxygen, the final electron acceptor. As electrons move through the chain, protons are pushed across the membrane to build the gradient needed for ATP synthesis. Electrons from NADH enter the chain at Complex I, also called NADH: ubiquinone oxidoreductase. In prokaryotes, this step helps pump protons from the...

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microbial fermentation

Fermentation Products in Microbes

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metabolism of chemolithotrophs

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amino acid catabolism

Microbes Use Proteins for Energy

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lipid catabolism

How Microbes Break Down Fats for Energy

Microbes break down triglycerides and fatty acids to make energy. Triglycerides are important long-term energy storage molecules in microorganisms. Lipases hydrolyze, or split with water, triglycerides into glycerol and free fatty acids. Each product then enters a different metabolic route that helps the cell make ATP, the main energy currency. Glycerol metabolism begins after glycerol is released from triglyceride hydrolysis. Glycerol kinase adds a phosphate group to form glycerol-3-phosphate.

oxygenic photosynthesis

How Plants Make Oxygen and ATP

Oxygenic photosynthesis is the process plants, algae, and cyanobacteria use to capture light energy and turn it into chemical energy. It uses water as the source of electrons and releases molecular oxygen, or O2. The process also produces ATP and NADPH, which cells need for later energy use and carbon fixation. The main reactions happen in the thylakoid membranes, where chlorophyll pigments absorb light. In cyanobacteria, these membranes come from folds in the plasma membrane. Two photosystems...

anoxygenic photosynthesis

Bacterial Light Capture Without Oxygen

Anoxygenic photosynthesis is a bacterial way to capture light energy without making oxygen. It supports carbon fixation, but it does not use water as the electron donor. Instead, these phototrophs use other electron donors such as hydrogen sulfide, elemental sulfur, thiosulfate, or organic compounds. This process is carried out by several groups of bacteria, including purple bacteria, green sulfur bacteria, heliobacteria, and other anoxygenic phototrophs. These organisms have evolved a...

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How Bacteria Build Key Macromolecules

Bacteria build essential macromolecules through tightly controlled biosynthetic pathways. These anabolic reactions make proteins, nucleic acids, lipids, and polysaccharides. The products support growth, cell division, and normal cell function. Bacterial biosynthesis starts with precursor metabolites from glycolysis, the pentose phosphate pathway, and the Krebs cycle. Important precursors include pyruvate, acetyl-CoA, and glucose-6-phosphate. Cells use these compounds to make the monomers that...

carbon-dioxide fixation

Microbial Carbon Fixation Pathways

Microbial carbon fixation pathways let prokaryotes turn carbon dioxide into organic molecules. This process supports biosynthesis, helps sustain ecosystems, and plays a role in the global carbon cycle. It also has industrial uses in carbon capture and bioproduct synthesis. Autotrophic organisms depend on this process to use CO2 as a carbon source in many environments. The Calvin cycle is the most common carbon fixation pathway. Cyanobacteria and other autotrophic prokaryotes use it, and it...

biosynthesis of polysaccharides

Activated Sugars for Polysaccharide Synthesis

Activated sugars drive polysaccharide synthesis in cells. Glycogen and starch are built from nucleoside diphosphate sugars, mainly uridine diphosphate glucose (UDPG) and adenosine diphosphate glucose (ADPG). These sugar donors act as high-energy intermediates in carbohydrate metabolism and biosynthesis. UDPG supports glycogen synthesis in animals and many bacteria. It forms when glucose-1-phosphate reacts with uridine triphosphate (UTP). UDP-glucose pyrophosphorylase catalyzes this reaction.

inorganic nitrogen assimilation

Nitrogen Uptake by Microbes

Nitrogen uptake by microbes is essential for making proteins, nucleic acids, and other cell parts. Many bacteria and archaea take in nitrogen as nitrate or ammonia. They then convert it into forms that can be built into biomolecules. When nitrate enters a cell, it goes through assimilatory nitrate reduction. This is a two-step process. First, nitrate reductase changes nitrate to nitrite using NADH or FAD as an electron donor, depending on environmental and cellular conditions. Then nitrite...

sulfur assimilation

Sulfur Uptake and Cysteine Synthesis

Sulfur uptake and cysteine synthesis are key parts of microbial metabolism. Sulfur is needed to build important biomolecules, including the amino acids cysteine and methionine, as well as cofactors such as coenzyme A and biotin. Microorganisms usually take in sulfur from the environment as sulfate, but sulfate must be changed before cells can use it. Because sulfate is highly oxidized, it must go through assimilatory sulfate reduction to become biologically useful. Some microorganisms can also...

amino acid biosynthetic pathways

Amino Acid Building from Cell Metabolites

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biosynthesis of nucleic acids

Nucleotide Building Blocks for DNA and RNA

Nucleotide biosynthesis makes the building blocks needed for DNA and RNA. Cells use this pathway to make purine and pyrimidine nucleotides and keep their supply balanced. That balance helps protect genetic integrity and supports normal cell function. Purine nucleotide synthesis starts with ribose-5-phosphate, a sugar made in the pentose phosphate pathway. PRPP synthetase adds phosphate groups to form phosphoribosyl pyrophosphate, or PRPP, which is the activated starting point for the pathway.

biosynthesis of lipids

How Membrane Lipids Vary Across Life

Membrane lipids vary across Bacteria, Archaea, and Eukarya, and these differences help cells survive in different environments. The three domains of life make lipids through distinct biosynthetic pathways. Those pathways create membranes with different stability, permeability, and flexibility. Bacteria and eukaryotes both build fatty acid-based lipids from acetyl-CoA and malonyl-CoA. The pathway includes condensation, reduction, and dehydration steps. Bacteria use a type II fatty acid...

formation of lipopolysaccharides

Lipopolysaccharides and Gram-Negative Defense

Lipopolysaccharides (LPS) are important parts of the outer membrane of Gram-negative bacteria. They help stabilize the membrane and help protect bacteria from host immune responses. LPS has three main parts: lipid A, a core oligosaccharide, and an O antigen. LPS biosynthesis and assembly depend on a coordinated set of enzymes and transport steps. The molecule is also known as an endotoxin. It can activate Toll-like receptor 4 (TLR4) in the host and trigger strong immune responses. In severe...

key terms and concepts

Learn how cells make and use ATP through substrate-level phosphorylation, oxidative phosphorylation, and photophosphorylation to power cell processes.

How Cells Make and Use ATP | JoVE K12

JoVE Core Microbiology provides an engaging introduction to the microbial world and its influence on health, industry, and the environment. This comprehensive collection covers key concepts such as microbial structure, metabolism, genetics, and ecology. It introduces essential laboratory techniques and microscopy methods through visually engaging animations. Corresponding scientist-in-action videos bridge classroom concepts with real-world research and applications.

microbiology

How Cells Make and Use ATP

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