A. METABOLISM - all biochemical reactions that transform matter, loose energy in addition to information
3 basic stages:
1. Uptake of substances (for example, across the plasma membrane)
2. Transformation of substances (anabolism or catabolism - explained a fleck later!)
3. Release of substances (for example, the elimination of metabolic wastes across the plasma membrane)
- at that topographic point are lots of interrelated reactions, thus it is hard to study
Image from http://www.expasy.org/biomap/images/pathway-1b.png
Metabolic pathway- the order inwards which reactions affecting a starting pith occur. A metabolic pathway may endure linear or circular in addition to the product (end substance) of i pathway may endure the reactant (starting substance) of another. Often reactions inwards a pathway are reversible.
All pathways conduct hold the next participants:
1. Substrates/reactants (kiindulóanyagok) - substances that locomote inwards the reaction
2. Intermediate products (köztestermékek) - compounds formed betwixt the get in addition to the cease of the reaction
3. Enzymes (enzímek) - proteins that catalyze (speed up) reactions
4. Energy carriers (energia hordozók) - unremarkably ATP. It donates loose energy to the reactions that require it in addition to picks upward loose energy from reactions that arrive at it.
5. End products(végtermékek)/metabolites (anyagcseretermékek) - substances produced at the cease of the pathway.
Chemical reactions are basically the discover of chemic loose energy past times breaking bonds inwards i pith in addition to so using it to practise novel bonds inwards approximately other substance.
2 Sides of Metabolism: Anabolism in addition to Catabolism
Anabolism (assimilation):
-all the synthesis or "building up" reactions inwards a cell.
-results inwards organic compounds (amino acids, lipids, etc) for loose energy storage, jail cellphone growth, repair, reproduction, etc.
-requires loose energy (endergonic)
What are the loose energy sources?
1. In autotrophs, they usage the loose energy from the Sun (photosynthesis) or from external chemic reactions (chemosynthesis). The cells convert external loose energy into ATP in addition to so usage the ATP to synthesize organic compounds.
2. In hetertrophs, the organisms conduct hold inwards (eat) organic compounds (food) in addition to intermission it downwards to synthesize ATP, so usage the ATP to synthesize their ain organic compounds.
Catabolism (dissimilation):
- this is also called cellular respiration
- organic compounds are broken downwards to discover the loose energy stored inwards them in addition to thus arrive at loose energy (exergonic)
-if this procedure occurs with O2 then it is biological oxidation and the products are CO2, H2O in addition to lots of energy (captured every bit ATP)
-if this procedure occurs without O2, so it is fermentation in addition to much less energy is produced (still captured every bit ATP)
-ATP tin endure used for diverse jail cellphone activities, such every bit biosynthesis, transport, jail cellphone division, movement, bioluminescence, etc, but approximately loose energy is also lost every bit heat.
B. ENZYMES
- nigh reactions require the input of loose energy (E) to teach started - this is called the activation energy. In the chemical scientific discipline lab, nosotros usage rut to supply the energy, but nigh living systems cannot withstand high temperatures, so enzymes are used. We telephone band them catalysts, because they lower the activation loose energy required for a reaction to occur past times forming temporary associations amongst the substrates.
-without enzymes, nigh metabolic reactions would endure likewise tedious to keep life.
Properties of enzymes
-they are globular proteins (tertiary or 4th structure) in addition to tin endure either uncomplicated (just the protein) or complex (protein + cofactor(inorganic, similar Mg)/coenzyme(organic, similar vitamin B or NAD+))
-they are specific: each enzyme entirely recognizes i or a few for certain substrates in addition to each enzyme tin entirely catalyze i variety of reaction (therefore at that topographic point are LOTS of dissimilar enzymes, nosotros know of over 2000!)
-a jail cellphone volition entirely industry the enzymes that it needs
-since enzymes are proteins, they tin endure denatured (structure in addition to business office destroyed) past times rut or pH changes
-they are non used upward past times a reaction, they tin endure reused many times
How enzymes work
-they are globular proteins amongst a groove or steal which forms the active site. This is where the substrate(s) fits into it in addition to the reaction is catalyzed.
-when the substrate binds to the enzyme it forms a temporary enzyme-substrate complex
-since the enzyme entirely binds to specific substrates, it is similar to the means entirely a specific cardinal fits inwards each lock, therefore, nosotros telephone band this the lock in addition to cardinal hypothesis of enzyme function
Image from http://hsc.csu.edu.au/biology/core/balance/9_2_1/image1.jpg
Naming Enzymes
- the kickoff enzymes to endure discovered were given names which are nevertheless used today (traditional names), eg. trypsin, pepsin
-most enzymes conduct hold a scientific name: substrate reaction+"ase"
eg. deoxyribonucleic acid polymerase (the substrate is DNA, the reaction forms a polymer or a long chain of DNA)
Enzyme Activity
1. pH - each enzyme has a "favourite" pH, fifty-fifty a slight alter inwards pH may campaign denaturation. In our digestive system, nosotros conduct hold diverse enzymes. Pepsin functions inwards the stomach, thus "likes" a pH of 2, spell trypsin, which is institute inwards the modest intestine, prefers a pH of 7.9-9
2. Temperature - for enzymes inwards our body, 37C is the "favourite" temperature. Influenza A virus subtype H5N1 lower temperatures, their activity slows, from 37-40C it speeds up, but to a higher house 40C H-bonds are broken in addition to their shapes are distorted (denaturation)
3. Enzyme-substrate concentration - amongst a given total of enzyme, the reaction charge per unit of measurement volition increase amongst an increase inwards substrate until all the active sites are constantly inwards use. Here it volition achieve a maximum in addition to inwards this case, the enzyme concentration is the limiting factor. If at that topographic point is an excess of enzyme amongst abide by to the total of substrate available, so the activity is substrate-limited.
Enzyme Inhibition
Enzymes are unable to business office if the active site is block or if the shape of the active site is changed. Different chemicals (or enzyme inhibitors) tin practise this in addition to so halt the enzyme from functioning. This is called enzyme inhibition in addition to at that topographic point are two types:
1. Competitive inhibition: the inhibitor takes the house of the substrate
Image from: http://www.peptide2.com/peptide/Enzyme_wikipedia_the_free_files/400px-Competitive_inhibition.png
2. Non-competitive inhibition: the inhibitor binds to the enzyme in addition to this causes a alter to the active site.
Image from: http://upload.wikipedia.org/wikipedia/commons/thumb/2/2b/Noncompetititve_inhibition.svg/800px-Noncompetitive_inhibition.svg.png
3 basic stages:
1. Uptake of substances (for example, across the plasma membrane)
2. Transformation of substances (anabolism or catabolism - explained a fleck later!)
3. Release of substances (for example, the elimination of metabolic wastes across the plasma membrane)
- at that topographic point are lots of interrelated reactions, thus it is hard to study
Metabolic pathway- the order inwards which reactions affecting a starting pith occur. A metabolic pathway may endure linear or circular in addition to the product (end substance) of i pathway may endure the reactant (starting substance) of another. Often reactions inwards a pathway are reversible.
All pathways conduct hold the next participants:
1. Substrates/reactants (kiindulóanyagok) - substances that locomote inwards the reaction
2. Intermediate products (köztestermékek) - compounds formed betwixt the get in addition to the cease of the reaction
3. Enzymes (enzímek) - proteins that catalyze (speed up) reactions
4. Energy carriers (energia hordozók) - unremarkably ATP. It donates loose energy to the reactions that require it in addition to picks upward loose energy from reactions that arrive at it.
5. End products(végtermékek)/metabolites (anyagcseretermékek) - substances produced at the cease of the pathway.
Chemical reactions are basically the discover of chemic loose energy past times breaking bonds inwards i pith in addition to so using it to practise novel bonds inwards approximately other substance.
2 Sides of Metabolism: Anabolism in addition to Catabolism
Anabolism (assimilation):
-all the synthesis or "building up" reactions inwards a cell.
-results inwards organic compounds (amino acids, lipids, etc) for loose energy storage, jail cellphone growth, repair, reproduction, etc.
-requires loose energy (endergonic)
What are the loose energy sources?
1. In autotrophs, they usage the loose energy from the Sun (photosynthesis) or from external chemic reactions (chemosynthesis). The cells convert external loose energy into ATP in addition to so usage the ATP to synthesize organic compounds.
2. In hetertrophs, the organisms conduct hold inwards (eat) organic compounds (food) in addition to intermission it downwards to synthesize ATP, so usage the ATP to synthesize their ain organic compounds.
Catabolism (dissimilation):
- this is also called cellular respiration
- organic compounds are broken downwards to discover the loose energy stored inwards them in addition to thus arrive at loose energy (exergonic)
-if this procedure occurs with O2 then it is biological oxidation and the products are CO2, H2O in addition to lots of energy (captured every bit ATP)
-if this procedure occurs without O2, so it is fermentation in addition to much less energy is produced (still captured every bit ATP)
-ATP tin endure used for diverse jail cellphone activities, such every bit biosynthesis, transport, jail cellphone division, movement, bioluminescence, etc, but approximately loose energy is also lost every bit heat.
B. ENZYMES
- nigh reactions require the input of loose energy (E) to teach started - this is called the activation energy. In the chemical scientific discipline lab, nosotros usage rut to supply the energy, but nigh living systems cannot withstand high temperatures, so enzymes are used. We telephone band them catalysts, because they lower the activation loose energy required for a reaction to occur past times forming temporary associations amongst the substrates.
-without enzymes, nigh metabolic reactions would endure likewise tedious to keep life.
Properties of enzymes
-they are globular proteins (tertiary or 4th structure) in addition to tin endure either uncomplicated (just the protein) or complex (protein + cofactor(inorganic, similar Mg)/coenzyme(organic, similar vitamin B or NAD+))
-they are specific: each enzyme entirely recognizes i or a few for certain substrates in addition to each enzyme tin entirely catalyze i variety of reaction (therefore at that topographic point are LOTS of dissimilar enzymes, nosotros know of over 2000!)
-a jail cellphone volition entirely industry the enzymes that it needs
-since enzymes are proteins, they tin endure denatured (structure in addition to business office destroyed) past times rut or pH changes
-they are non used upward past times a reaction, they tin endure reused many times
How enzymes work
-they are globular proteins amongst a groove or steal which forms the active site. This is where the substrate(s) fits into it in addition to the reaction is catalyzed.
-when the substrate binds to the enzyme it forms a temporary enzyme-substrate complex
-since the enzyme entirely binds to specific substrates, it is similar to the means entirely a specific cardinal fits inwards each lock, therefore, nosotros telephone band this the lock in addition to cardinal hypothesis of enzyme function
Image from http://hsc.csu.edu.au/biology/core/balance/9_2_1/image1.jpg
Naming Enzymes
- the kickoff enzymes to endure discovered were given names which are nevertheless used today (traditional names), eg. trypsin, pepsin
-most enzymes conduct hold a scientific name: substrate reaction+"ase"
eg. deoxyribonucleic acid polymerase (the substrate is DNA, the reaction forms a polymer or a long chain of DNA)
Enzyme Activity
1. pH - each enzyme has a "favourite" pH, fifty-fifty a slight alter inwards pH may campaign denaturation. In our digestive system, nosotros conduct hold diverse enzymes. Pepsin functions inwards the stomach, thus "likes" a pH of 2, spell trypsin, which is institute inwards the modest intestine, prefers a pH of 7.9-9
2. Temperature - for enzymes inwards our body, 37C is the "favourite" temperature. Influenza A virus subtype H5N1 lower temperatures, their activity slows, from 37-40C it speeds up, but to a higher house 40C H-bonds are broken in addition to their shapes are distorted (denaturation)
3. Enzyme-substrate concentration - amongst a given total of enzyme, the reaction charge per unit of measurement volition increase amongst an increase inwards substrate until all the active sites are constantly inwards use. Here it volition achieve a maximum in addition to inwards this case, the enzyme concentration is the limiting factor. If at that topographic point is an excess of enzyme amongst abide by to the total of substrate available, so the activity is substrate-limited.
Enzyme Inhibition
Enzymes are unable to business office if the active site is block or if the shape of the active site is changed. Different chemicals (or enzyme inhibitors) tin practise this in addition to so halt the enzyme from functioning. This is called enzyme inhibition in addition to at that topographic point are two types:
1. Competitive inhibition: the inhibitor takes the house of the substrate
2. Non-competitive inhibition: the inhibitor binds to the enzyme in addition to this causes a alter to the active site.
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