KREBS CYCLE

BIOCHEMISTRY - Krebs cycle
Krebs cycle, tricarboxylic-Citric Acid
Krebsdisebut cycle as well: Because the citric acid cycle is the first compound to form citric acid.
Also called the Krebs cycle CYCLE tricarboxylic acid (-COOH) Since almost the beginning of Krebs cycle, tricarboxylic acid compounds are composed of. It is a tricarboxylic acid group (-COOH).
Because the Krebs cycle is found is Mr.Hans Krebs, a renowned biochemist, who discovered the metabolism of carbohydrates as well.
The main function of the Krebs cycle is the final pathway of oxidation Carbohydrates, Lipids and Proteins. Carbohydrates, fats and protein will be metabolized into Asetyl all-CoA.

Vision and Mission of the Gaza respiration is producing energy.
So if we eat carbohydrates in the mouth will be digested maltose (by ptyalin) and the end result is glucose in the duodenum it will go into the cells undergo glycolysis, which will ultimately result in an atmosphere of pyruvic acid pyruvic acid cytoplasm where there was so mitocondria certain aerobic full oxygen pyruvic acid will then continue the process of change into the Pre asetyl Co.A Krebs cycle (oxidative dekarbosilasi). as well as in lipid and then into fatty acids and fats are broken down à asetyl gliserol.Asam Co.A, undergo a process called lipolysis. Protein is converted into amino acids then become asetyl Co.A krebstersebut OK at the beginning of the cycle


From the above diagram the formation of a strategic Acetyl Coa has the lead role in gluconeogenesis (formation of Glycogen), transamination, deamination (breakdown of protein / amino group) and lipogenesis (fat formation)

Is a process of formation of glucose from non-carbohydrate material. How? Can wrote, because when someone is having a very low carbohydrate intake (perhaps hunger strike, extreme kelaperan) that is not matched by adequate carbohydrate intake, your body will still form glucose. But because there was no carbohydrate so the material is not a carbohydrate but fat or protein. OK
This is one of the mechanisms of the body in an attempt to maintain glucose levels in normal circumstances.
for vitamins, minral and water could not be used in this
Glucose is essential for the body as the main energy source of brain and red blood cells.
After eating, glucose levels will increase, the main mechanism Glycolysis occurs.
Conversely When we eat a lot, then glucose must be stored so that blood sugar levels are not increased.
Form of glucose stored in the body is glycogen.
Storage of excess glucose there will be a process of glycogenesis in the liver requires insulin from the pancreas.
Conversely, if in a state of hunger, fasting, exercise aerobics or so, then the need for glucose to rise, so the savings will be split glucose through the process of glycogenolysis. (Demolition of Glycogen into glucose in the liver with the help of Adrenalin / Glucagon
So the essence of the metabolism of carbohydrates is to maintain glucose levels in normal circumstances. OK
In order to know the normal levels of glucose in the blood à approximately 80-126, below the level that it will suffer from hypoglycemia, the top level is called hyperglycemia (in diabetes mellitus)
So it could mean that the process is explained clearly involve gluconeogenesis involves
Krebs cycle.
Transamination is a process to transfer or exchange of amino groups (alpha-amino) a keto group (alpha-keto) or vice versa.
Examples of alpha-amino group into amino acids (glutamate, aspartate, etc.)
In order to really understand it Asama amino composed of various amino acids:
Essential amino acids
amino acid non esesnsial
Amino acid essential amino acids needed by the body but the body can not form
Examples of essential amino acids: phenylalanine, isoleucine, leucine, lysine, methionine, tryptophan, threonine and valine, arginine and histidine
Non-essential amino acid that is required by the body but the body can be formed
example: alanine, asparagine, aspartic acid, cysteine, glutamate, glutamine, glycine, hydroxyproline, hydroxylysine, proline, serine, and tyrosine.

For the formation of amino acids transminasi is non-essential amino acids. So it could be called a process transminasi also the formation of amino acids from alpha-keto acid.
Examples of alpha-keto group having CO (alpha-keto glutaric acid, oxaloacetic acid)
The main one is at transamination of alpha-ketoglutarate and acetate oksalo
Deamination
Deamination is the process of release of the amino group (group containing N).
Deamination process is a concrete example that eating protein in the body will then be converted into amino acids and amino acids will be broken again that the end result is ammonia.
But because it is highly toxic ammonia, ammonia was not present in blood, especially in the brain, then it is converted into urea.
Urea then be excreted through the kidneys.
Ammonia has a smaller concentration than urea.
In fact, it may not be any ammonia in the urine.
then why there is ammonia in urine? Where does ammonia urine? Ammonia is produced in the kidney, with the aim that occur acid-base balance.
So in fact the end result of ammonia, but because it is toxic, the ammonia was taken to the liver to be converted into urea. The bottom line is the end product of protein urea.

Urea is formed from ammonia was then introduced into the blood to be discarded due to the excretion of materials
It should be understood that deliver blood from the heart instead of urea is OK Kidney
Renal blood freed of urea by the process of filtration and reabsorption Augmentation to bener bener free blood urea
Urea and creatinine are mixed with water and the excess substance called Urine kemudyan
So if there are disturbances in renal ammonia then certainly piling up, what happens? then there is ammonia poisoning.
How the solution?
Of course we need to consume foods that are low in protein. So that the resulting levels of ammonia can not be banyak.OK
What if there is still a stumbling block so far as the task of the liver organ urea excretion when baseball throw?
Excretion of the liver as the organ is to free the blood from damaged blood carcass into bile OK
Lipogenesis i
Lipogenesis is the process of fat formation.
Lipogenesis substrate is asetyl Co.A
Asetyl Co.A obtained from glycolysis to continue to Oxidative decarboxylation
People who consume a high carbohydrate, then in the body is converted into fat.
Ga wonder then that many people can eat ndut. hehe of course is the same as cows that only eat carbohydrates (cellulose) in the grass was too fat cow

So with our meal, we provide a substrate for respiration chain (in the form of hydrogen or electrons).
Respiratory chain into the cellular level respiration is related to the electron jump., The material is essentially of the Krebs cycle, the hydrogen ion.
All the metabolic processes that result is CO2, which is then disposed of as expiratory air
When we inhale O2 and O2 is used for the oxidation process is O2 carried by hemoglobin to the cells and in cells used for the O2-burn combustion sources of energy, good carbohydrates, fats and proteins which are then the result of CO2
CO2 is then transported back through the lungs to the body in expirasi.
But not all the CO2 removed, there are few or a small portion is used for the formation of fat.
Since the formation of CO 2 requires an absolute fat.
The Krebs cycle is the result of CO2, ATP, hydrogen ions or reducing equivalents (reducing agent) are bound by the FAD and NAD
So if O2 as oxidizing agent.
Hydrogen ions are à material for cellular respiration.
Krebs cycle
Definition of Krebs Cycle
Is a series of reactions that occur in the mitochondria that carry residue asetyl catabolism, liberate an equivalent of hydrogen, by oxidation which causes the release and capture of ATP as the network's energy needs.
Asetyl residue in the form of asetyl-CoA (CH3-CO-S-CoA, acetate is active)
Purpose of the Krebs Cycle

Explain the metabolic reactions contained a final common biochemical pathway in the catabolism of force main
Illustrates that CO2 is not only the end result of metabolism, but can serve as intermediates, for example, to process lipogenesis.
Recognizing the central role of mitochondria in catalysis and control of specific metabolic pathways, mitochondrial function as an energy producer.
Function
Produce most of the CO2
Other metabolic pathways that generate pentose phosphate such as CO2 or P3 (pentose phosphate pathway) or if the harper hexose monophosphate.
Source of enzymes-enzymes that encourage reduced RR (respiration chain)
Is a tool that excessive force may be used for the synthesis of fat before the formation of TG for fat storage
Provide important precursors for subunits are required in the synthesis of various molecules
Provides a control mechanism, directly or indirectly to other enzyme systems

Krebs Cycle Cycle

Carbohydrates, Protein and Fat / Lipid is the end result will be metabolized into asetyl Co-A, where asetyl Co-A is a substrate for the Krebs cycle.
Then the CO2 generated from the Krebs cycle, hydrogen (FAD NAD) and ATP.
Hydrogen (reducing equivalents) is the substrate for respiration chain (RR).
Krebs cycle must run dalamSiklus Citric Acid (Krebs Cycle)

Description:
Krebs cycle substrate is asetyl Co-A.
Asetyl Co-A will react with oksalo acetate (OAA) à result of citric
Citric acid formula with different ascorbic acid (vitamin C), when vitamin C was more like a formula of glucose. Humans can not produce vitamin C because there is a reaction that is lost when humans did not have the enzyme L-glunoluase oxidase which oxidizes glucose to vitamin C.
Of alpha-ketoglutarate isositrat to release CO2 and NADH (coenzyme).
If the result would require NAD NADH.
À NAD in the oxidized form
In the reduced form NADH à
NAD is a derivative of vitamin B3.
À B1 thiamin
À B2 riboflavin
À B3 niacin
Associated with ATP coenzyme vitamin B2 and B3 only.
Vitamin B deficiency would interfere with energy metabolism.
NADH dehydrogenase isositrat à enzyme.
NADH will go into respiratory chain releasing hydrogen and generating three ATP. Whereas FADH 2 produces ATP
Oxidative decarboxylation à CO2 release.
Of alpha-keto into succinyl Co-A oxidation à decarboxylation process.
Of succynyl Co-A into a direct succinate produced ATP.
Reactions that produce ATP directly: Krebs cycle, glycolysis, oxidative phosphorylation, and respiration chain.
Most of the fat-producing ATP but does not generate ATP directly. Fat lot of produce NADH and FADH.
Of succinate to fumarate generated FADH2, requires coenzyme FAD (derivatives of vitamin B2), 2 ATP produced.
Oxaloacetat generated from NADH to Malate 3 ATP.
Total ATP for 1 round (1 asetyl Co-A) à 12 ATP Krebs cycle.
Glycolysis à 2 asetyl Co-A
Fat à 8 asetyl Co.A
1 mol glucose à 2 turns
1 mol of fatty à 8 rounds
Carbohydrates are stored in the rickshaw-spotting in the hepatic cytoplasm.
Hepatic glycogen stores can survive à 0.5 gram
Mjd glycolysis serves to oxidize the CO 2 and also save energy to form a high-energy molecules such as ATP, NADH, FADH2
Oxidative within the central respiratory cycle in which all macromolecules à dikatabolis (Carbohydrates, Lipids and Proteins)
For sustainability requires: NAD, FAD, ADP, Pyr (pyruvate) and OAA
Important intermediate compounds which produce à acetyl Co A, a KG and OAA
Amino acids resulting from alpha-ketoglutarate through glutamate à transamnasi process. If oxaloacetate à aspartic acid
A precursor for the biosynthesis of macromolecules - Macromolecules
Krebs cycle than as the final pathway of carbohydrates, fats and proteins, is also the beginning of the path ari macromolecules.
Late catabolism pathway à à à change asetyl Co.A KH
Initial path à anabolism
Function in the catabolism and anabolism also à amfibolik
À catabolism produces high energy molecules
Anabolism à producing intermediate precursor for the biosynthesis of macromolecules

So in each cycle:
An acetyl group (molecular 2C) in and out as 2 molecules of CO2
In each cycle: OAA to form citrate is used after a reaction à à re-acquired long OAA
Consists of 8 comments: 4 mrpkn oxidation à à where energy is used to reduce NAD and FAD
Generated: 2 ATP, 8 NADH, 2 FADH2
O2 is not required at the TCA, but it is used in oxidative phosphorylation to supply à NAD, pyruvate SHG can be transformed into Acetyl Co A
Vs Glycolysis Krebs cycle (TCA)
Glycolysis Krebs cycle
a. Running a linear reaction
b. A location in the cytoplasm. Cyclical reaction
b. lies in the mitochondrial matrix

Binding of acetyl-CoA CHEMICAL PROCESS BY ACETATE INTO OKSALO citrate
FOLLOWING FORMULA COMPOUNDS INVOLVED IN THE WAKE of the Krebs cycle
Available enzymes in the mitochondria
There are two kinds of enzymes:
require NAD
requires NADP
NADP-dependent enzyme: located in the mitochondrial matrix and cytosol



Role in anabolism shown by Krebs cycle intermediates 4, namely:
A. Citric
Can be used to form cholesterol or fatty acids. If there is interference or obstacles in a systematic change in citrate citrate accumulate akusitrat so for example, the citrate will be accumulated and can increase cholesterol or fatty acids.
2. Alpha-ketoglutarate
Through the process of generating the amino acid glutamate transamination.
À if too many purines in the body is converted into uric acid, can increase the concentration of uric acid in the blood. Uric acid in the body to function as endogenous antioxidants.
3. Succynil Co-A
Used to mensitesis hem. Hem + à globin protein hemoglobin.
If in the plant, succynil Co-A is used for the formation of chlorophyll.
Heme and chlorophyll formula exactly the same formula, except that heme binding is Fe metal in the middle, while the chlorophyll in the middle of the Mg metal.
Oksalo acetate
Through the process of transamination, into aspartate transaminase enzyme, purine and pyrimidine.
EXEMPTION ATP by the Krebs Cycle

Krebs cycle as a metabolic pathway amfibolik
Amfibolik called anabolism and catabolism à.
Example:
a-ketoglutarate + pyruvate + glutamate alanine à
à oxaloacetate aspartate + alanine + pyruvate
succinyl co-A, is prazat for haem biosynthesis
Krebs cycle reactions as Amfibolik Metabolism Path
The reactions of the Krebs Cycle Anaplerotik
Put a lot of pyruvate or asetyl Ko-A into the Krebs cycle can reduce inventory okasaloasetat used for citrate synthase.
Two reactions are used to meet the needs of oxaloacetate called rx anaplerotik (meet)
Pyruvate into oxaloacetate
Pyruvate into malate
On weight-trained muscle tissue, AMP into IMP by oxidative deamination. The net result to form fumarate
Anaplerotik When the intermediate reaction product of TCA / Krebs cycle is used as a biosynthetic precursor of other

À à intermediate concentration slows down the speed of TCA There are 5 comments:
Pyruvate to the enzyme pyruvate carboxylase with OAA
PEP with the enzyme PEP into OAA karboksikinase
PEP to OAA with the enzyme PEP carboxylase
Dg malic enzyme pyruvate into malate
Transamination reactions: aspartate to OAA and glutamate into a-ketoglutarate

Once again in Krebs Siklkus we can know
Metabolic pathway of tricarboxylic acid cycle (citric acid) was first discovered by Krebs (1937).
Therefore, this pathway is also called the Krebs cycle. This cycle path is a major metabolic ajlur of the metabolism of various compounds, namely the catabolism of carbohydrates, fats, and proteins.
Acetyl co-A (as a result of catabolism of fats and carbohydrates), oksalasetat, fumarate, and α-ketoglutarate (sebagaihasil katabolismeasam acids and proteins), into the Krebs cycle for further oxidized through several stages of a complex reaction to CO2, H2O and energy ATP.
Tri carboxylic acid cycle activity present in animal cells, plants, and microorganisms are aerobic metabolism and is a major energy producer. Bodies that do not use the anaerobic metabolism of this cycle as a producer of energy.


Krebs cycle is the series of the respiratory process is long and complex, the oxidation of glucose to CO2dan H2O and ATP production.
Respiratory process consists of four main stages:
glycolysis (oxidation of glucose to pyruvate)
conversion of pyruvate to acetyl co-A
Krebs cycle and
the transport of electrons through the respiratory chain is coupled to the synthesis of ATP from ADP degan = Pi through the phosphorylation process is oxidation.
In the cells of eukaryotes, takes place in the tricarboxylic acid metabolism mitokondrion. Most of these metabolic enzymes in the liquid contained in the matrix and partly attached to the inside of the membrane mitokondrion.