Topic 11: Amino Acid Anabolism

Question 1

What are the ESSENTIAL AAs?

Answer 1

PVT. TIM HALL

Phe, Val, Thr, Trp, Ile, Met, His, Arg, Leu, Lys

FVTWIMHRLK

Any Help In Learning These Little Molecules Proves Truly Valuable

Question 2

What are the NON-essential AAs?

Answer 2

Ala, Asp, Asn, Cys, Glu, Gln, Gly, Pro, Ser, Tyr

Question 3

How do we make Glu?

Answer 3

from a-KG via Glutamate-DH, transaminases, etc.

Question 4

How do we make Gln?

Answer 4

from Glutamate via GLUTAMINE SYNTHETASE (implies we need ATP)

Question 5

How do we make Ala?

Answer 5

from Pyruvate via ALT/SGPT

Question 6

How do we make Asp?

Answer 6

from OAA via AST/SGOT

Question 7

How do we make Asn?

Answer 7

from Asp via ASPARAGINE SYNTHETASE (implies we need ATP)

Question 8

How do we make Tyr?

Answer 8

from Phe via PAH

Question 9

How do we make Pro?

Answer 9

from Glutamine

Glu –> Glutamine semialdehyde becomes Glutamic semialdehyde by losing H+ then spontaneously delta-Pyrroline-5-carboxylate (ring closes) –> via Pyrroline-5-carboxylate Reductase is reduced to become the ringed PROLINE Amino Acid

Question 10

How do we make Serine?

Answer 10

from 3-PhosphoGlycerate from step 6 glycolysis

3-phosphoglycerate (Step 6 Glycolysis) via 3-PGDH becomes 3-phosphopyruvate (generates NADH) –> AAtransferase takes amino from GLU to make 3-Phosphoserine –>
Phosphatase removes phosphate to make SERINE! (uses H2O in this step)

Question 11

How do we make Glycine?

Answer 11

From SERINE in the presence of tetrahydrofolate and enzyme REMOVE h2O to make GLYCINE!!

Question 12

How do we make Cysteine?

Answer 12

from METHIONINE and ATP (need Serine too)

Met + ATP –> Adomet –> Adenosylhomeocyteine –> Homocysteine + Serine –> link via Sulfur –> CYSTEINE takes sulfur and also get alpha-ketobutyrate

This is the normal breakdown pathway of Methionine

Question 13

What are the CONDITIONALLY ESSENTIAL AAs?

Answer 13

Cysteine (Cys/C): Neonates
Tyrosine (Tyr/Y): PKU animals
Glutamine (Gln/N): growing infants and severe illness
Arginine (Arg/R): infants, children, severe illness

CYNR

Question 14

What are the Carbon Sources for non-essentials?

Answer 14

Glucose makes:

Pyruvate –> Alanine
OAA–> Aspartate
alpha-ketoglutarate –> Glutamate
3-Phosphoglycerate –> Serine

Question 15

What is Taurine used for?

Answer 15

Membrane stabilization
NeuroINHIBITORY transmitter
Primary Conjugate of BILE - especially in CATS

Question 16

Is Taurine a sulfonic acid or carboxy acid?

Answer 16

Sulfonic Acid!

Question 17

What vitamin does Taurine require?

Answer 17

B6/Pyridoxine

Question 18

What is the issue with taurine and mostly-plant diets?

Answer 18

TAURINE DEFICIENT! must eat meat!!!!!

Question 19

What are symptoms of TAURINE Deficiency?

Answer 19

Heart Failure! (Dilated Cardiomyopathy), Retinopathy, Renal Disease, Fat/Emulsification absorption (or lack there of), reproductive failure, immune deficiency

Question 20

What is Glutamate capable of as a neurotransmitter?

Answer 20

STIMULATORY itself

can make GABA –> INHIBITORY

MSG–> chinese restaurant syndrome –> fidgity, head aches,

Question 21

What is Glycine capable of as a neurotransmitter?

Answer 21

INHIBITORY in the spinal cord, blocking motor impulses,

Question 22

What is Tyrosine capable of as a neurotransmitter?

Answer 22

It’s NOT, BUT it is the foundation for:
Dopamine: INHIBITORY voluntary movement, tremors –> PARKINSON’S
Norepinephrine: SNS –> heart rate, sweating, vasoconstriction
Epinephrine: glycogen metabolism, fight or flight, uses Methionine for methyl group

Question 23

Should you be able to recognize Tyrosine structure?

Answer 23

YES HE SAID KNOW THE STRUCTURE

its AA with a phenyl ring and a hydroxy (OH) hangin off the ring

Question 24

What hormone is Tyrosine important for?

Answer 24

THYROXINE!

Question 25

What other products (not NT or hormone) can be derived from Tyrosine?

Answer 25

Melanin and CoQ (ETC-OxPhos)

Question 26

What can be derived from Tryptophan?

Answer 26

Serotonin (be happy) and Melatonin (sleep)

Question 27

What can be derived from Hisitidine?

Answer 27

HISTAMINE! vasodilator, bronchoconstriction, HCL secretion in stomach

Question 28

What can be derived from Arginine?

Answer 28

NITRIC OXIDE! relaxes Vascular and Smooth Muscle neurotransmitter, stimulates immune cells

cAMP mechanism

Question 29

What AAs are required for Creatine formation?

Answer 29

Arrrrrrrginine, Glycine, Methionine
Arg, Gly, Met
RGM

Question 30

What NONESSENTIAL Amino Acid CANNOT be made from glucose??

Answer 30

Tyrosine –> need the essential Phenylalanine for it!