Amino Acid Metab: Alba's Powerpoint Flashcards
(97 cards)
1
Q
this AA is an immediate precursor of urea
A
arginine
2
Q
this AA is a precursor of NO
A
arginine
3
Q
AA functions as an excretory neurotransmitter
A
aspartate
4
Q
inhibitory neurotransmitter; precursor of heme
A
glycine
5
Q
precursor of histamine
A
histidine
6
Q
precursor of serotonin
A
tryptophan
7
Q
precursor of melatonin
A
tryptophan
8
Q
precursor of catecholamines
A
tyrosine
9
Q
carrier of ammonia
A
alanine
10
Q
carrier of carbons of pyruvate from skeletal muscle
A
alanine
11
Q
heavily implicated in the cori cycle
A
alanine
12
Q
free amino acids of plasma
A
glycine and alanine
13
Q
the __ group of this AA is incorporated into creatine
A
guanadino of arginine
14
Q
the C skeleton of this AA is converted to putrescine, spermidine, and spermine
A
arginine
15
Q
the C skeleton of arginine is converted to __
A
putrescine, spermidine, and spermine
16
Q
this AA participates in the formation of CoA
A
cysteine
17
Q
cysteine > CoA via the enzyme
A
4-phosphopantothenoyl-cysteine
18
Q
when cysteine is oxidized, it is converted to __
A
taurine
19
Q
when cysteinsulfate is decarboxylated, it will be converted to ___
A
hypotaurine
20
Q
glutathione is derived from this AA
A
cysteine
21
Q
glycine conjugates include
A
glycocholic acid and hippuric acid
22
Q
nitrogen and a-C of glycine is incorporated into pyrrole rings of
A
heme
23
Q
AA is involved in the formation of heme
A
glycine
24
Q
what parts of glycine are implicated in heme formation
A
nitrogen and alpha-carbon
25
glycine molecule helps form which atoms of what nucleotide
atoms 4,5,7
of
purine
26
by what process is histidine converted to histamine
dexarboxylation
27
what are other formations of histidine in the body?
ergothionine, carnosine, and dietary anserine
28
what AA is the major source of methyl groups in the body
methionine
29
what are the 3 enzymes that are responsible for the conversion of methionine to s-adenosylmethionine
methionine adenosyltransferase (MAT)
MAT1 and 3 are hepatic
MAT2 is not
30
what is the root cause of hypermethioninemia
decreased MAT 1 and 3
31
this AA helps in the formation of spermine and spermidine
methionine
32
what AA associates readily with DNA and RNA
methinoine
33
tyrosine is a precursor of...
catecholamines
T3 (triiodothyronine)
T4 (thyroxine)
34
what is involved in the biosynthesis of sphingosine
serine
35
explain relationship of serine and nucleotides
serine provides carbons 2 and 8 of purine
serine provides the methyl group of thymine
36
homocystinuria is caused by
defects in Cystathionine Beta Synthase
37
what phosphorylated amino acids are involved in the activity of enzymes related to lipid and carbohydrate metab?
STT
- phosphoSerine
- phosphoTyrosine
- phosphoThreonine
38
what AA arises from the methylation of glycine
sarcosine
39
what do we use as a meausre of proportionate muscle mass
24-h urinary creatinine
40
what 3 enzymes are implicated in creatinine biosynthesis
GAMe
- glycine
- arginine
- methionine
41
what 2 AAs are formed during the catabolism of pyrimidines
B-alanine and
| B-amino isobutyrate
42
what AA is GABA derived from
glutamate
43
catabolism of an AA begins with:
the removal of alpha amino group
alpha amion group transferred to
a-KG and OAA
excreted ultimately as urea
44
AA provide __
- precursors for biosynthesis of signaling molecules, hormones, and neurottransmitters
45
what are the AAs that directly release NH4?
glutamate and histidine
GH
46
what are the AAs that indirectly release NH4?
serine and threonine
ST
= via dehydration
47
what initiates AA catabolism
transamination
48
what catalyzes transamination
where is this not seen
aminotransaminase
except in
LYS THREE PROPRO
49
enzyme transaminase is strictly specific for
a-KG (accepts a-NH2)
and
L-amino aicds
50
what AAs do tumors need for growth
asparagine
51
what is treatment for tumor growth at the level of AAs
give asparaginase for asparagine to be converted to aspartate
52
differentiate
Type I Hyperprolinemia
from
Type II Hyperprolinemia
1: blocked glutamate semialdehyde DH
2: blocked proline DH
53
in hypeornithinemia, what is the recommended dietary restriction?
no arginine
54
how can you detect folic acid deficiency? what AA is implicated here?
FIGLU
via histidine
55
what are the amino acids that can form pyruvate
```
alanine
serine
glycine
cysteine
threonine
```
SCAgLY TREE
56
glycinuria is due to
defecive renal tubular absorption
KIDNEY PROBLEM = ABSORPTION
57
transamination of alanine forms?
pyruvate
58
transamination of ? forms pyruvate
alanine
59
serine catabolism merges with ___ and releases
tetrahydrofolate
60
cysteine calculi is due to
cystinuria
61
cystinuria is due to
a defect in renal absorption of CYSTEINE ORINTHINE ARGININE AND LYSINE
COAL
62
threonine can be converted to ___ via threonine aldolase
glycine
63
3 causes of PKU
1. deficient phenylalanine hydroxylase
2. deficient tetrahydrobiopterin as a cofactor
3. defect in recycling tetrahydrobiopterin
64
MSUD - biochemical defect involving
alpha-keto acids
65
MSUD - genes involved
E1 a
E1 B
E2
E3
66
AAs derived from fumarate
aspartate
phenylalanine converted to tyrosine
67
AAs that form succinyl-CoA
methionine, threonine, valine, and isoleocine
IL-MVT
succinyl CoA
68
AA related to TCA cycle intermediates
GLUe HAPpens
- glutamate, glutamine, histidine, arginine, proline
69
nitrogen balance in pregnant women
POSITIVE
more nitrogen intake compared to excretion
70
nitrogen balance in children
POSITIVE
71
nitrogen balance in cancer
NEGATIVE
72
nitrogen balance in fasting people
NEGATIVE
73
solid form or irc acid
guano
74
where is pyridoxal phosphate (PLP) from
vitamin B6
75
what amino acids participate in transamination?
everything except
LYS THREE PROPRO
76
hyperammonemia 1
CPS1
77
CPS1 deficiency
hyperammonemia 1
78
NAG synthase deficiency
hyperammonemia 1
same as CPS1 deficiency
79
HHH syndrome is due to
deficiency in orinthine permease
80
features of HHH syndrome
hyperorinthinemia
hyperammonemia
homocitrullin-uria
81
what gene codes for HHH syndrome
ORNT1 gene
82
what gene codes for orinthine permease
ORNT1 gene
83
orinthine transcarbamoylase deficiency
hyperammonemia 2
84
hyperammonemia 2
deficient orinthine transcarbamoylase
85
what serves as an increase in the risk of hyperammonemia 2 in babies?
mother has hyperammonemia and mother lacks protein in diet
86
what AA-related feature is seen in hyperammonemia 2?
increased glutamine in:
blood, CSF, and urine
87
what happens when there is a deficiency in arginosuccinate synthase?
extremely high Km for citrulline
88
deficient arginosuccinate lyase
arginosuccinic-aciduria
= high arginosuccinate in blood, CSF, and urine
= seen in amniotic fluid or umbilical cord
89
arginosuccinicaciduria is due to
a deficiency in arginosuccinate lyase
90
arginase deficiency
hyperargininemia
91
hyperargininemia is due to ?
arginase deficiency
92
what is the urinary pattern of an individual with hyperargininemia
lysine-cysteine-uria
93
what is the method of regulation of the urea cycle?
feed forward mechanism
94
what happens with the urea cycle when there are higher levels of ammonia?
upregulated
i.e.
more cycles
95
what is NAG made of?
acetyl-CoA + glutamate
96
what stimultes the production of NAG?
arginine
97
what represses/SLOWS DOWN the urea cycle enzymes
high protein diet or prolonged fasting
