Amino Acid And Alcohol Metabolism Flashcards
What is the difference between amino acid catabolism as use for energy compared to lipid
Amino acids are not stored and only synthesised when needed eg to make enzymes
What 2 reasons do we need amino acid catabolism
Remove excess amino acids from blood
Provide energy if little glucose present
How do free amino acids come about
Proteins are recycled if not needed
What is amino acid pool used for
Produce metabolic intermediates for example in citric cycle either for glycolysis or gluconeogenesis
What is the difference between essential AA and non essential
Essential- amino acids only provided by diet
Non essential- ones we can get from recycling of proteins
How does starvation using amino acid catabolism causing death
Because macro molecules like antibodies are broken down to supply the amino acids for catabolic pathway to form intermediates
Functioning proteins are lost
Which 7 intermediates are formed by amino acids
Acetyl coa Pyruvate Oxaloacetate A ketoglutarate Acetoacetyl coA (ketogenesis) Succinyl coA Fumarate
Which part of an amino acid is used for energy production
Carboxylate, R and H = CARBON SKELETON
Carbon is oxidised for energy remember
What happens to the amino group in liver
Converted to urea from ammonia and then excreted as waste
What are glucogenic amino acids
AA used for gluconeogenesis
What are ketogenic AA
Generate ketones eg generation of acetoacetyl coA from amino acids
And acetyl coA
Which enzymes are key in amino acid metabolism
Transaminases
Amino acid transferases
How are amino acids converted into intermediates
Amino acid transferases with swap the amino group for a keto group
Eg forming a ketoglutarate from glutamate and keto group
How are amino acids returned back from intermediates
Addition of an amino acid again
What does a free amino ability to move generate
Many different amino acids that are now non essential due to the synthesis from intermediates
The amino group adds into their carbon skeleton = nee amino acid produced
How many amino acids are non essential due to AA metabolism
11
How does eg aspartate transferase enzyme work
Glutamate adds an amino group to oxaloacetate whilst picking a keto group up itself
This forms aspartate from the amino addition to oxaloacetate and also forms a ketoglutarate from addition of a keto onto glutamate
In an amino acid transferase (transaminase) reaction where is the amino group transferred to in order for a amino acid to add a keto
Transferred to another amino acid carbon skeleton so produces 1 new amino acid from the addition of amino and a different intermediate from addition of a keto
Give an example of essential and non essential amino acids
Essential - phe, tyr,
Non essential - glutamate, alanine, aspartate
Which amino acid does ethanol increase response to (why it’s called depressant)
GABA
Which good cholesterol does ethanol increase
HPL
Where is alcohol removed and converted by detoxification
Liver
What happens when liver reaches its maximum alcohol consumption
Body becomes anaesthetic and increase blood alcohol and death if too much
What is ethanol converted to first in detoxification and how
Converted to acetal aldehyde (toxic)
By the reduction of NAD into NADH
By alcohol dehydrogenase
How is acetal aldehyde removed
Converted by reduction of nad to NADH by aldehyde dehydrogenase
Into acetic acid
What happens to pyruvate due to the build up of NADH by liver alcohol metabolism
Converted into lactate to regenerate NAD
What happens due to high atp present and also NADH from alcohol metabolism
Ketones will be produced instead
= acidosis
Acetoacetate into 3 hydroxybutyrate
What does NADH from alcohol metabolism inhibit causing hypoglycaemia and also Lipogenesis
Gluconeogenesis and the citric acid cycle (stops in presence of NADH)
Acetyl coA will be converted to lipids instead
Because alcohol causes Lipogenesis, what disease is linked to this
Fatty liver disease and also type 2 diabetes
Why do some people suffer more from hangovers
Polymorphic changes in dna which mean they have insufficient aldehyde dehydrogenase so more acetal aldehyde builds up = sickness
How do drugs treating alcoholism work
They induce hangover symptoms purposely
