Glycolysis Overview Flashcards
What is the purpose of Glycolysis?
To break down glucose in order to produce ATP
What are the products of glycolysis?
ATP, NADH, Pyruvate, lactate and alanine
In aerobic organisms glycolysis yields precursors to the Aerobic system which is composed of these two systems
Krebs cycle and ETS
The aerobic system completely ______ CO2 and H20
Oxidizes
During the first half of glycolysis Glucose is brought into the cell and it is _______ so it is trapped within it
Phosphorilated
During the first half of Glycolysis glucose is changed into an energy rich sugar known as
Fructose 1,6 biphosphate
In the second half of glycolysis when we receive the ATP we:
Split the molecule in two in order to get ATP, Set up large Delta G reactions , and use the free energy to re-create ATP
In the second half of glycolysis the end product that could be further oxidized is
Pyruvate
After glycolysis what does pyruvate enter into?
Aerobic system
What transporter helps glucose get in the cell?
GLUT 4
Glucose is located in the ?
Cytosol
What does Hexokinase do in glycolysis?
Phosphorilate Glucose to convert it to Glu 6-Phos
After the phosphate group is added, glucose can go through ______ which is enabled by phosphoglucose isomerase thus changing its structure
Isomerization
During Isomerization we change the aldehyde structure into a ________
ketone
In order to further transform Glucose into a more energy rich sugar, This enzyme phosphorylates Fru 6–phosphate and turns it into _______
PFK (phosphofructokinase) and turns it into Fructose 1,6-biphosphate
What does Bis-phosphate imply?
Two separate phosphates
What does Diphosphate imply?
Two joined phosphates
What is PFK (Phosphofructokinase)?
It is an allosteric enzyme
What makes PFK important?
It is the rate limiting enzyme in glycolysis
What is allosterism?
The influencing of an enzyme activity by a change in the conformation of the enzyme, brought about by the noncompetitive binding of a nonsubstrate at a site (allosteric site) other than the active site of the enzyme.”
During the first half of glycolysis , _______ utilizes the Phosphate group in ATP and phosphorylates glucose in order to form Glucose 6-Phosphate
Hexokinase
Phosphoglucose isomerase rearranges Glucose 6-Phosphate by changinge the _______group into a _______group in order to turn it into Fructose 6- Phosphate
Aldehyde; ketone
PFK utilizes the Phosphate group in ATP and breaks it down in order to ______ Fructose 6-Phosphate in order to transform into ________
phosphorylate; fructose 1,6 biphosphate
During the second half of Glycolysis the molecule is _____ in order to set up large negative Delta G reactions and use the free energy to recreate ATP
Split into two
During “the split” in the second half of Glycolysis, this enzyme splits up Fructose 1,6 biphosphate into 2 3 carbon sugars known as _______
Aldolase; glyceraldehyde 3 phosphate
During the second half of glycolysis, In the isomerization process this ENZYME rearranges the ______ group into an ______ group
Triose phosphate isomerase; Ketone ; aldehyde
How many pyruvates are yielded per glucose?
2
Glyceraldehyde 3 phosphate undergoes ________ in order to become 1,3 biphosphoglycerate
oxidative phosphorylation
What is the enzyme that catalyzes oxidative phosphorylation in G3P -> 1,3 Biphosphoglycerate reactions?
G3P dehydrogenase
1,3 biphosphoglycerate has one of the phosphate groups removed. This group binds with ADP to become ATP. The molecule that results from this is _____
3- phosphoglycerate
What is the enzyme that removes the phosphate group from 1,3 biphosphoglycerate?
Phosphoglycerate kinase
In order for 3- phosphoglycerate to become 2- phosphoglycerate it must mutate by using this enzyme
phosphoglycerate mutase
2 phosphoglycerate undergoes ______ in order to become phosphoenolpyruvate
dehydration
What is the enzyme that plays a key role in the dehydration reaction of 2- phosphoglycerate?
Enolase
What is an enol?
A compound possessing a hydroxyl group attached to a doubly bonded carbon atom (–CH=CH (OH) –)
What is substrate level phosphorylation?
Phosphate from the substrate helps make atp
Phosphoenolpyruvate undergoes _____ ____ ___ in order to become pyruvate and produce ATP
Substrate level phosphorylation
What is the enzyme that plays a key role in the Phosphoenolpyruvate substrate level phosphorylation reaction?
pyruvate kinase
What other prominent monosaccharides enter the glycolytic pathway?
fructose and galactose
Fructose can be phosphorylated to fructose 6P by _____ and then enter glycolysis
hexokinase
Galactose is converted into glucose 6P in _ steps
4
Which enzymes converts Galactose into Galactose 1P via phosphorylation?
Galactokinase
Which enzyme is utilized in the Galactose 1P + UDP glu reaction in order to produce Glucose 1p?
Transferase
Which enzyme is used in the UDP galactose -> UDP glucose reaction?
Epimerase
What enzyme is used in the Glucose 1p -> glucose 6P reaction?
Mutase
What are the key enzymes in the glycolytic pathway?
Hexokinase
Phosphofructokinase Pyruvate Kinase
What is the starting point for the Krebs cycle and also inhibits PFK?
Citrate
What binds to PFK and decreases its activity?
ATP
_____pH inhibits PFK
Decreased
It is better to regulate PFK during the process in which Glu6P becomes _____
Fructose 1,6 Biphosphate
What are the two pathways that G6P can take?
Glycogen synthesis and Pentose phosphate pathway
The more Fructose 6P we have in low ATP situations the _____ the reaction
the faster
Which enzyme catalyzes the first step in glycolysis?
Hexokinase
Inhibition of which enzyme leads to inhibition of Hexokinase
PFK
Which enzyme elevates the concentration of F6P and then G6P
PFK
What enzymes do the liver and beta cells of the pancreas contain?
Glucokinase
Name an alternative form of Hexokinase
glucokinase
This enzyme also makes G6P but only does so when glucose is _______
abundant
What is glucokinase stimulated by?
Insulin and fructose
Glucokinase has a ____ ___ which means it takes more reactant to make it go faster
High Km
Glucokinase is not inhibited by _________
Glucose 6phosphate
This enzyme catalyze the third irreversible step in glycolysis. It is also stimulated by fructose 1,6 BP
Pyruvate kinase
This amino acid is one reaction away from becoming pyruvate
Alanine
Which hormone is secreted when glucose is low?
glucagon
What is the objective of glucagon and its primary target?
elevate blood glucose and its primary target is the liver
Pyruvate + NADH → Lactate + NAD+
no answer just memorize
Which enzyme is required for the dehydrogenation reaction of Pyruvate into lactate?
Lactate dehydrogenase
When is lactic acid produced?
when glycolysis runs fast
A moderate production of lactate ____ glycolysis
speeds up
A large production of lactate _____ glycolysis
inhibits
What is the warburg effect?
Conversion of glucose to lactic acid in the presence of oxygen
Invasive cancers tend to have
Altered glucose metabolism
During acidosis, running glycolysis fast creates intracelullar and pericelullar
acidic conditions