gluconeogenesis

Liver

Kidney cortex

The two sites of gluconeogensis

The conversion of non-carbohydrate units into carbohydrates

What is gluconeogenesis

Source of glucose during fasting

Cori cycle

The 2 functions of gluconeogenesis

Cori cycle

The conversion of lactate to glucose during/after excessive exercise

Brain, RBC’s

Body parts that relay on glucose for their main not source of energy

Lactate, amino acids, glycerol

Major noncarbohydrate precursors of glucose That are converted to pyruvate or later intermediates for glycolysis

Skeletal muscles form lactate through lactic acid fermentation

How lactate is formed

In the liver, lactate turns to pyruvate lactate dehydrogenase

How is lactate converted to pyruvate

Protein in the diet

Starvation, breaking down proteins in skeletal muscle

Derivations of AA to be a glucose precursor

1. Glycerol using enzyme glycerol kinase and reaction of ATP to ADP glycerol phosphate is formed

2. Glycerol phosphate then using enzyme glycerol phosphate dehydrogenase and reaction NAD+ to NADH + H+ to form dihydroxyacetone phosphate

Series of reaction glycerol must go through to enter gluconeogenesis or glycolysis pathway

Bicarbonate

Biotin

Pyruvate carboxylase

ATP to ADP

Oxaloacetate

Irreversible

The first step of gluconeogenesis reactant, cofactor, enzyme, enzyme reaction, product, reversibility

In the mitochondria

In the cytosol of the cell

The reaction converting pyruvate to oxaloacetate occurs …

1. Is reduced to malate by malate dehydrogenase

2. Malate leaves the cell and turns back to oxaloacetate by reduction with the enzyme NAD+ linked malate dehydrogenase

3. NADH is also made for further gluconeogenesis steps

Oxaloacetate made in the mitochondria is unable to leave, instead it

Oxaloacetate

N/A

Phosphoenolpyruvate carboxykinase

GTP to GDP

Phosphoenolpyruvate and CO2

Reversible

Step 2: oxaloacetate phosphorylation: reactant, coenzyme, enzyme, enzyme reaction, product, reversibility

Fructose-1,6-bisphosphate & water

N/A

Fructose-1,6-bisphosphate

N/A

Fructose-6-phosphate & phosphate

Irreversible

Step 3: hydrolysis of fructose-1,6-bisphosphate: reactant, coenzyme, enzyme, enzyme reaction, product, reversibility

Fructose-1,6-bisphosphate

Interconversion of Phosphoenolpyruvate and pyruvate in the liver

Enzyme that is the primary regulation point of gluconeogenesis … , … also regulates

Liver

Glucose-6-phosphate

Generation of free glucose usually only occurs in … , in other tissues gluconeogenesis stops at the formation of …

In the lumen of the endoplasmic reticulum (liver). Glucose-6-phosphatase a integral membrane in the reticulum catalyzes the reaction of glucose-6-phosphate to glucose through hydrolysis

Almost at the final stage of gluconeogenesis, glucose-6-phosphate is trapped …

Transporters located on the membrane of the endoplasmic reticulum transfer glucose and a phosphate into the cytoplasm

Once glucose-6-phosphate is turned to glucose by glucose-6-transferase

The body prefers to go through glycolysis to create ATP for energy, also gluconeogenesis takes 6 energy molecules for the reactions to fully occur whereas glycolysis only requires 2

Formation of glucose from pyruvate is pretty unfavourable because

Fructose-2,6-bisphosphate

Phosphofructokinase

Fructose-1,6-bisphosphate

The key regulator of glucose metabolism in the liver is that stimulates … for glycolysis to continue and inhibit … to stop gluconeogenesis …

Bifunctional enzyme

This enzyme made of a kinase and phosphate domain, PFK 2 and FBPase2 determines the levels of F_26-BP

Insulin is secreted stimulating glycolysis and inhibiting gluconeogenesis

When blood glucose is high

Glucagon is secreted to stimulate gluconeogenesis and inhibits glycolysis

When blood glucose is low

Type 2 diabetes, type 1 diabetes

Condition where insulin fails to act but is still present … , … is where it is not made (destroyed by immune cells)

The muscle produces lactate during contraction which is then released in the blood( the muscle goes through glycolysis). The liver ten removes the lactate from the blood Turing it to glucose then rereleased into the blood (the liver goes through gluconeogensis)

The inter cooperation of the Cori cycle is:

It acts as a CO2 carrier in carboxylation reactions. Its also called V B7

What is the use of biotin