Enzymes and Metabolism

Energiestoffwechsel

• Enzymes are used in medicine, fruit processing, leather treatment, and cheese ripening.
• Examples include Bromelain and Trypsin for anti-inflammatory treatment, Lactase for lactose intolerance, and Pectinase for fruit processing.

Enzymatik im Blickpunkt Industrie

• Enzymes catalyze reactions specifically and efficiently in small quantities, reducing energy input.
• The food industry is the largest user of enzymes, followed by the textile and detergent industries.
• Enzymes are used to control production processes and in the manufacturing of everyday products, pharmaceuticals, medicine, and in the environmental and energy sectors.

Enzyme in Waschmitteln

• Proteases, obtained from animal pancreases in the early 20th century, remove protein stains from laundry by breaking them down into amino acids and short-chain peptides.
• Modern detergent proteases are derived from Bacillus licheniformis, which synthesizes Subtilisin, an enzyme tolerant of low temperatures and high pH levels (9-10).
• Lipases and amylases are added to detergents to remove fats and starches at lower temperatures.
• Risks associated with enzyme use in detergents include allergic reactions and water pollution.
• Low washing temperatures may lead to microbial growth in washing machines.

Massgeschneiderte Enzyme

• Subtilisin loses effectiveness in the presence of bleach due to oxidation of its active center by oxidizing substances like hydrogen peroxide.
• Scientists optimize enzymes by identifying bacterial strains with mutations that produce oxidation-resistant enzymes.
• Protein engineering involves modifying bacterial cells using artificial genetic information to produce modified enzymes.
• Genetically modified microorganisms are used to produce additives like flavor enhancers, vitamins, and dyes in the food industry.

Enzyme in Medizin und Diagnostik

• Lactase enzyme supplements help lactose-intolerant individuals digest milk products.
• Enzymes are used to treat blood clots and in the production of medications and diagnostics.

Enzyme in der Lebensmittelindustrie

• Chymosin, an enzyme from calf stomachs, has been used for over 8000 years to produce cheese.
• Today, proteases are obtained from plants like pineapples and genetically modified microorganisms.
• In 1987, the gene for calf chymosin synthesis was deciphered, isolated, and inserted into microorganisms.
• Amylases are used to break down corn or potato starch into glucose for sugar production.
• Glucose isomerase converts glucose into fructose, producing glucose-fructose syrup used in soft drinks and sweets.

Stoffwechsel und Energie

• During a marathon, muscles require a constant energy supply, often supplemented with bananas or carbohydrate gels.
• The body requires energy for both activity and basic functions like brain activity, heartbeat, and breathing.
• Cells use energy to prepare substrates or enzymes for reactions and transport molecules against concentration gradients.
• The energy used to maintain basic functions is called the basal metabolic rate.
• Additional physical activity increases energy consumption, requiring more energy.
• The thermoregulation of the body to adapt to different ambient temperatures, increases energy demand by approximately 5 to 10%.
• The total metabolic rate comprises basal metabolic rate, activity metabolic rate, diet-induced thermogenesis, and thermoregulatory energy expenditure.
• $Gesamtumsatz = Grundumsatz + Leistungsumsatz + nahrungsbedingter \ und \ temperaturregulierender \ Energieumsatz$
• During a marathon, the energy requirement is approximately 10500 kJ, only partially covered by food intake during the run.

Bedeutung von ATP

• Cells make chemical energy available via ATP formed during metabolic processes.
• ATP serves as the universal energy carrier of the cell.
• ATP is a nucleotide made up of the organic base adenine, the sugar ribose and three phosphate groups.
• ATP readily hydrolyzes into ADP and inorganic phosphate, releasing energy that phosphorylates other molecules to facilitate reactions.
• ATP is continuously synthesized because each ATP molecule is consumed on average within 1 minute.

Energiespeicher des Körpers

• Glucose absorbed from food is present in small amounts in blood plasma and can be processed to meet the immediate energy needs of the cells.
• Energy reserve in the form of carbohydrates: Glycogen, a long-chain compound made up for many glucose molecules. Stored in the liver and skeletal muscles. Limited storage provides energy for one day while at rest.
• Another major energy store is muscle protein.
• The largest energy store are lipids in fat tissue cells: Fats are primarily used for energy supply during low, long-lasting exercises because the processes of fat degradation take more time.
• Well-trained people are also able to utilize fat reserves during high-intensity exercises. Training makes it possible to effectively combine and use two storage methods.

Nutzung der Energiespeicher

• The respiratory quotient (RQ) is the ratio of carbon dioxide produced to oxygen consumed, determined from exhaled and inhaled air.
• RQ values vary depending on the fuel source: 1.0 for carbohydrates, 0.7 for fats, and 0.8 for proteins.
• RQ values provide insights into the energy source used during muscle work.
• For marathon runners, RQ indicates when fat burning begins.

Hungerstoffwechsel

• The hunger metabolism allows the survival from internal energy stores for a certain time.
• The transitions can be divided into different phases in which different reserves are used to maintain the life functions.
• The human body can survive for about 17 to 75 days without any outside nutrition.
• The brain uses messenger compounds to control the change of metabolic processes.
• Gluconeogenesis: The conversion of proteins in the body (e.g. muscle protein) into carbohydrate/glucose for energy production in cell respiration.

Phasen des Hungerstoffwechsels

• Phase 1 (4-24 hours): Glycogen is broken down in the liver, fat reserves begin to be used, and gluconeogenesis attempts to use protein reserves.
• Phase 2 (24-48 hours): Glycogen reserves have been used up, the consumption of fat reserves increases, and gluconeogenesis from protein reserves declines slightly.
• Phase 3 (2-7 days): there are no glycogen reserves left, fat reserves account for 85% of the energy source, and gluconeogenesis from protein reserves accounts for 15%.
• Phase 4 (7-28+ days): Fat and protein breakdown plateaus.

Energiebedarf und geistige Anstrengung

• The brain accounts for only about 2-2.5% of body mass, yet it consumes 22-26% of resting energy.
• Muscles make up 33-43% of body weight but consume only 20-25% of resting energy.
• The liver also has a relatively high energy consumption of 20-22% with only 2-2.5% of body mass.
• The basal metabolic rate for a 70 kg person is approximately 70 kcal/hour
• Schachspieler -> 140kcal/h, Autofahren -> 140kcal/h, Putzen -> 260kcal/h, Spazierengehen -> 400kcal/h, Schwimmen -> 700kcal/h, Joggen -> 800kcal/h, Boxen -> 1500kcal/h.
• During tasks requiring mental effort (chess game), the heart rate increases.
• The brain is unable to store a lot of glycogen; an uninterrupted stream of glucose from the blood is necessary.
• A study showed that participants consumed more calories after mental effort, with stronger swings in sugar and insulin levels.

Gasaustausch

• Gas exchange provides oxygen for cell respiration and removes carbon dioxide.
• The lungs contain around 300 million alveoli for gas exchange.
• Gas exchange occurs in three phases: external respiration, respiratory gas transport, and cell respiration.
• Driving forces of diffusion: Partial pressure gradients of O2 and CO2.
• Only 4ml O2 per liter, while in comparison 200 ml O2 per liter in red blood cells when Hämoglobin is active.
• The Hämoglobin in the red blood cells increases the capacity by 50 times.

Zellatmung im Überblick

• Zellatmung includes the three sections Glykolyse, Citratzyklus and Atmungskette.
• Mitochondria are organelles with two membranes as shell. The inner membrane is folded and invaginated.
• In the mitochondrial matrix a number of reaction steps take place (Citratzyklus).

Redoxreaktion

• A is oxidised Electronendonator, B is reduced Electronenakzeptor

Glykolyse

• Muscles fibers are crushed and set with glucose
• Blackbox-Methode
• Cells of a tissue are supplied with specific materials and measured
• By providing muscle pulp, glucose, increased amount of Glucose-6-phosphat and Fructose-6-phospat could already be confirmed after a short time
• Experiments with cell homogenates
• Only cell plasm and mitochondrium must work together for converting glucose and oxygen.
• Substances are made in the cell plasm after several steps, from glucose pyruvate develops into oxygen.
• In the Mitochondriem Oxygen in consumed and ATP develops
• To from Pyruvat glucose molecules must be zerlegt
• The gradual breakdown of glocose into pyruvat = Glykolyse.
• Three phases of Glykolyse:
• First phase -> ATP consumption and making of Fructose-1,6-bisphosphate to provide
• Second phase -> 3 -Phospho-glycerat = ATP is formed and energy is returned
• Third phase -> ATP is formed. Energy to the transfer of energy
• Balance for the Glykolyse two molecules ATP per glucose molecule
• Glykolyse must run to NAD+ ADP
• A high ATP => stops the Prozess.

Citratzyklus

• Ketoglutarat → Succinat Fumarat Malat Oxalacetat
• Pyruvat (glykolyse) with release of Carbon dioxid related an the reaction of Oxalacetat to Citrat
• Reaktionskreislauf
• NADH + H+ FADH2

Atmungskette

• In experiments it could be confirmed that the consumption of oxygen takes only place when Plasma and Mitochondrien are provided
  The outer Mitochond membrane must be emoved

• The fragments are resolved in a mixture of membran protein

• Then they get seperated by Chromatography and get examined.

  Morbus Tarui

  *Enzym deficiency zytoplasma
  *kontraktion Muscles 1/4