Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

619 macronutrient metabolism > Protein metabolism Part 2 > Flashcards

Protein metabolism Part 2 Flashcards

1
Q

Glutamine

A

Source of energy for intestinal cells; growth effects, strengthens intestinal barriers (mucosa call proliferation; mucin synthesis)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Glutamate

A

Used for alanine, proline, ornithine synthesis; very little glutamate leaves intestinal cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Aspartate

A

Generate OAA then ornithine; little ASP leaves intestinal cell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Arginine

A

Up to 40% oxidized in enterocytes—–> citrulline and urea; citrulline used in arginine synthesis in kidneys

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Methionine and cysteine

A

Up to 52% of MET metabolized in the gut; cysteine from methionine or from diet used to make glutathione

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Key role of glutamine

A

ammonia transport

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

In extrahepatic tissues, glutamine synthetase catalyzes

A

utilization of ammonia with glutamate to produce glutamine (ATP dependent)

-ammonia is generated from AMP deamination in muscle (AMP generated with ATP deamination in muscle)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Glutamine is formed in ______ from _______ of _____ with ______

A

glutamine is formed in muscle and other cells from transamination of branched chain amino acids with a-ketoglutarate to form branched chain amino acids and glutamate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

The glutamine that is formed in the muscle is released into

A

the blood and transported for use by other tissues

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Cells of the GI tract and immune system rely on glutamine catabolism for

A

energy production

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

In the kidneys absorptive state, liver glutaminase activity increases yielding

A

ammonia for urea cycle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

In acidotic state, the liver releases glutamine

A

into the blood for transport to and uptake by kidneys for acid base cycle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

glutamine use by cells increases with

A

hypercatabolic conditions- glutamine stores can become depleted

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

describe the steps for formation of glutamine

A
  1. glutamine is generated in muscle as branched-chain amino acids are transaminated with a-ketogluterate
  2. some glutamate is deaminated to yield a-ketogluterase and ammonia
  3. ammonia is also formed from AMP deaminase. AMP is generated in muscle from ATP degradation
  4. Glutamine synthetase catalyzes the formation of glutamine from ammonia and glutamate
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

transamination reactions in muscle generate

A

glutamate which is used in fed state to synthesize glutamine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

alanine is generated in the _____ while glucose is generated in the _____

A

muscle, liver

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

The alanine-glucose cycle serves to transport

A

transport nitrogen and regenerate substances

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Glutamate transamination with pyruvate generates

A

alanine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Leucine transamination with a-ketoglutarate generates

A

Glutamate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

List the steps of the Cahill Cycle

A
  1. Alanine is formed in the muscle from transamination with glutamate (generated from leucine transamination and from pyruvate 9generated from glucose oxidation via glycolysis)
  2. Alanine travels in the blood to the liver
  3. In the liver, alanine is transaminated with a-ketogluterate to form pyruvate
  4. Pyruvate can be converted back to glucose in a series of reactions
    5.THe glucose is released into the blood for uptake by tissues such as muscle
  5. The glutamate formed in the liver can be deaminated to release ammonia; the ammonia is used in the liver for urea production
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

List the steps of the Cahill Cycle

A
  1. Alanine is formed in the muscle from transamination with glutamate (generated from leucine transamination and from pyruvate 9generated from glucose oxidation via glycolysis)
  2. Alanine travels in the blood to the liver
  3. In the liver, alanine is transaminated with a-ketogluterate to form pyruvate
  4. Pyruvate can be converted back to glucose in a series of reactions
    5.THe glucose is released into the blood for uptake by tissues such as muscle
  5. The glutamate formed in the liver can be deaminated to release ammonia; the ammonia is used in the liver for urea production
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Which amino acids to muscles preferentially catabolize

A

aspartate, asparagine, glutamate, leucine, isoleucine, valine

22
Q

Valine oxidation generates

A

succinyl-coa (glucogenic)

23
Q

Isoleucine catabolism generates

A

succinyl-coa and Acetyl Coa (glucogenic and ketogenic)

24
leucine oxidation
acetyl coa and acetoacetate (ketocenic)
25
Kidneys roles in AA metabolism
-glutamine catabolism for acid base balance -Glycine catabolism for acid-base balance -Serine synthesis from glycine -Arginine and glycine for creatine synthesis -Glutathionine catabolism -Arginine synthesis from citrulline -Tyrosine synthesis from phenylalanine -Histidine generation from carnosine degradation
26
Kidneys are major site for which AA production
Histidine, arginine, serine, tyrosine
27
In kidneys, glutamine uptake has been estimated at ____ but increases with ____
7-10g per day, increases with acidosis
28
glycine is -___ by the kidneys to form
degraded by kidneys to form ammonia and carbon dioxide- synthesis of amino acid serine
29
What for the kidneys filter blood plasma and constituted
glomeruli filter blood plasma
29
What for the kidneys filter blood plasma and constituted
glomeruli filter blood plasma
30
What are reabsorbed by the kidneys glomular filter
Na, amino acids, glucose and those that
31
what happens to substances that are not reabsorbed from the glomular filter
must move along electrical gradient to enter tubular cells, and then are excreted
31
8what happens to substances that are not reabsorbed from the glomular filter
must move along electrical gradient to enter tubular cells, and then are excreted
32
80% of nitrogen lost in urine as _____ under normal conditions
urea
32
80% of nitrogen lost in urine as _____ under normal conditions
urea
33
Other nitrogenous substances found in urine
creatinine, uric acid, creatine, protein, AA, hippuric acid
34
Brain has a ___ ___ for aa transport
high capacity, transporters for some AA almost fully saturated at normal plamsa concentrations
35
Describe what happens in PKU and MSUD with AA transporters
competition for transporters pose issue in inborn errors of metabolism -PKU - high phenylalanine -MSUD- high BCAA< increased uptake at expense of AA
36
Liver disease has high _____ aa
aromatic amino acids
37
Glycine as a neurotransmitter
inhibitory neurotransmitter within spinal cord
38
Taurine as a neurotransmitter
inhibitory neurotransmitter
39
Aspartate as a neurotransmitter
Excitatory neurotransmitter in CNS; derived from glutamate through aspartate amino transferase activity
40
Glutamate as a neurotransmitter
excitatory neurotransmitter; used for GABA synthesis
41
Glutamate acts in the ___ as excitatory neurotransmitter
brain and spinal cord
42
Glutamate can be decarboxylated to produce ___ by the enzyme ___
Gama amino butyric acid - glutamate decarboxylase which is vitamin B6 dependent
43
Gaba functions in the brain as a
inhibitory neurotransmitter in the brain
44
Which amino acids are biogenic
-Tryptophan -tyrosine -histidine
45
Tryptophan is used to synthesize
serotonin
46
How is tryptophan converted to serotonin
Hydroxylation and decarboyxlation -Hydroxylation (L-tryptophan-5-HTP) -decarboylation of 5-HTP to 5-HP) -decarboxylation of 5-HTP to 5-HT is B6 dependent -degreattion of serotonin to 5-HIAA via monomine oxidase
47
what is tyrosine used to synthesize
catecholamines in sympathetic neurons
48
what can tyrosine by converted to
catecholamines A. Dopamine= executive function; coordination of movement, reinforcement B. Norepinephrine: alertness, emotions, sleeping, dreaming C. Low concentration in brain; systematically exerts catabolic functions within metabolic pathways
49
How is tyrosine converted to catecholamines
Tryosine -tyrosine hydroxylase 1. L-DOPA -amino acid decarboxylase 2. Dopamine -dopamine B-hydroxylase 3. Norepinephrine -phenylethanoalmine-N-methyltransferase 4. Epinephrine

619 macronutrient metabolism (5 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions