Biochem FA Flashcards
What is peroxisomal disease causes scaly skin, ataxia, cataracts, shortening of the 4th toe and epiphyseal dysplasia?
Refsum disease
What are the 4 main ways of getting B12 deficiency?
Malabsorption - D. Latum, celiac
Lack of intrinsic factor
No terminal ileum
Vegan
CFs of Homocystinuria?
Inc Homocysteine in urine Osteoporosis Marafanoid body Ocular changes CVA effects KYphosis Retard
Classic galactosemia is an absence of what?
Inheritance?
Galactose-1-phosphate uridyltransferase
AR
How do you dx B1 deficiency?
Increase in rbc transketolase activity following B1 admin
What is Vit B6 called?
B7?
B12?
Pyridoxine: PLP
Biotin
cobalamin
What are the glycogen storage disease I-V?
Inheritance?
Very Poor Carbohydrate Metabolism I - Von Gierke II- Pompe III - Cori V - McArdle
AR
What can be used to treat APL?
All Trans retinoic acid
Souther blot tests what?
Northern?
Western?
SNoW DRoP –> DNA
RNA
Protein
What drugs can cause folate deficiency?
Vit what?
PMS - phenytoin, methotrexate, sulfonamides
B9
Thiamine is required for which enzyme reactions?
think ATP: Alpha-ketoglutarate dehydrogenase (TCA) Transketolase (HMP shunt) Pyruvate dehydrogenase (TCA) branched-chain ketoacid dehydrogenase
What inhibits ribonucleotide reductase?
Hydroxyurea
What confirmatory test is used for HIV after ELISA?
Western blot
What manifests as elfin facies, intellectual disability, hypercalcemia, extreme friendliness w/strangers and cardiovascular problems?
Ch.?
Williams syndrome
Deletion ch. 7
What familial dyslipidemias have AR inheritance?
I, III
Hyperchylomicronemia - LPL or ApoCII deficiency
Dysbeta-lipoproteinemia - defective ApoE
ApoA-I fx?
Activates LCAT
What disease shows inappropriate laughter, seizures, ataxia, and mental retard?
Due to what?
Angelman syndrome
Imprinting - maternal gene deleted
Dec affinity of cystathionine synthase for what can result in Homocystinuria?
Pyridoxal phosphate (B6)
Vit E fx?
Deficiency causes what?
Antioxidant
Hemolytic anemia, acanthocytosis, m. Weakeness
What is a disorder in which there is a defect in N-acetylglucosaminyl-1-phosphotransferase, decreased M6P, and results in course facial features, clouded corneas, restricted joint movement?
Presents when?
What abnormal lab value?
Inclusion cell disease
Childhood, fatal
High levels of lysosomal enzymes
What presents w/severe fat malabsorption, steatorrhea, failure to thrive. Later it presents w/retinitis pigmentosa, spinocerebellar degeneration, ataxia, acanthocytosis?
Tx?
Abetalipoproteinemia
Restrict long chain FAs, Give Vitamin E
1g carb produces how many Cal?
1g alcohol?
1g FA?
4
7
9
Type 1 collagen is found in what?
2?
Bone
Cartilage aka carTWOlage, virtreous body, nucleus pulposus
G6PD produces what kind of rbc changes?
Most common in whom? Why?
Heniz bodies
Bite Cell
AA’s, increased malarial resistance
What is type 3 cartilage?
Deficiency results in what?
Reticulin, blood vessels, skin, uterus, fetal tissue
Vascular type Ehlers-Danlos
What inhibits DHF reductase?
Methotrexate
Trimethoprim
Pyrimethamine
Kwashiorkor results from what?
CFs?
Protein malnutrition
MEALS Malnutrition Edema Anemia Liver (fatty) Skin lesions
Vit B9 is converted to what?
Important for what reactions?
Deficiency causes what 2 main conditions?
THF
Synthesis of nitrogenous bases in DNA and RNA
Macrocytic/megaloblastic anemia and hypersegmented polymorphonuclear cells (PMNs)
B3 is derived from what a.a.?
What is derived from B3?
Deficiency leads to what?
Tryptophan
NAD (3 ATP)
Pellagra - diarrhea, dementia, dermatitis (hyperpigmentation of sun-exposed limbs)
What is the result of absent HGPRT?
Inheritance?
CFs?
Leach-Nyhan syndrome
X-linked recessive
Hyperuricemia, gout, Pissed off (self-mutilation), retard, dysTonia
Von Gierke disease has what deficient enzyme?
Main CFs?
Tx?
Glucose-6-phosphate
Severe fasting hypoglycemia, HM (Inc glycogen in liver), Inc uric acid, blood lactate, etc
Freq oral glucose/cornstarch, NO fructose/galactose –> impaired gluconeogensis and glycogenolysis
What familial dyslipidemias have AD inheritance?
II, IV
Familial hypercholesterolemia - absent LDL
Hyper Triglyceridemia - overproduction of VLDL
Dry beriberi has what sx?
Wet?
Polyneuritis, symmetrical muscle wasting
High output cardiac failure (dilated cardiomyopathy), edema
What inhibits Dihydroorotate dehydrogenase?
Leflunomide
What is the most common urea cycle disorder which will have findings of orotic acid in the blood and urine w/dec BUN?
Inheritance?
Orinthine transcarbamylase deficiency
X-linked recessive
Tay-Sachs has what deficient enzyme?
What accumulates?
Cfs?
Hexosaminidase A
GM2 ganglioside
Neurodegeneration, Cherry red spot on macula, lysosomes w/onion skin
Cystinuria can cause what kind of stones?
Tx?
Hexagonal cystine stones
Urinary alkalization, chelating agents
What is the cori cycle?
Pyruvate —> Lactate
LDH
FA synthesis starts where? Ends where?
Requires what starting material?
What special process? What enzyme?
Mitochondria, ends in cytosol
Citrate
Citrate shuttle, ATP citrate lyase
What is a mutation at different loci which can produce a similar phenotype called?
Ex?
Locus heterogeneity
Albinism
Gaucher disease deficient enzyme?
What accumulates?
CFs?
Glucocerebrosidase (beta-glucosidase)
Glucocerebroside
MOST COMMON - HSM, pancytopenia, osteoporosis
Krabbe disease deficient enzyme?
What substrate accumulates?
CFs?
Galactocerebrosidase
” “ psychosine
Peripheral neuropathy, destruction of oligodendrocytes, developmental delay, optic atrophy, globoid cells
Deficiency of alpha-L-iduronidase causes what?
Inheritance?
CF?
Hurler syndrome
AR
Developmental delay, gargoyle, CORNEAL clouding, HSM
What causes PKU?
CFs?
Tx?
Decreased Phenylalanine hydroxylase or Decreased BH4
Intellectual disability, growth retardation
Dec phenylalanine and Increase Tyrosine intake
Anticipation is seen in what conditions?
Trinucleotide repeat disease - ex. Huntington’s
B12 is a cofactor for what reactions?
Prolonged deficiency leads to what?
Methionine synthase and methylmalonyl-CoA mutase
Irreversible nerve damage
ApoB48 fx?
Mediates chylomicron secretion into lymphatics
Cystic fibrosis mutation? What ch.?
Inheritance?
CFs?
CFTR, ch. 7
AR
Recurrent pulmonary infections, nasal polyps, clubbing of nails
Arsenic inhibits what?
Which stops what?
Lipoic acid
PDH complex
What a.a. Are basic?
Most basic is which one?
+ or - charged?
His Lys Are (Arginine) Basic
Arginine
+
Lactase deficiency demonstrates what in the stool in terms of:
pH?
Hydrogen?
Dec pH
Inc Hydrogen
Increased homocysteine but normal methylmalonic acid level indicates what?
What special feature about it?
1 vit def in US
Folate def.
What are the 4 irreversible enzymes in gluconeogenesis?
Pathway Produces Fresh Glucose
Pyruvate carboxylase in mito. Pyruvate –> oxaloacetate
PEP carboxykinase in cytosol. oxaloacetate –> PEP
F-1,6-BPtase in cytosol
G6Ptase in ER
Is PFK-2 or FBPase-2 active in the fasting state?
What is increased?
Result?
FBPase-2
cAMP, PKA
More gluconeogenesis
Defect of NER results in what?
Prevents repair of what?
Xeroderma pigmentosum
Pyrimidine dimers
Cori disease deficient enzyme?
Cfs?
Debra Ching enzyme alpha-1,6-glucosidase
Accumulation of limit dextrin-like structures in cytosol
What is the storage form of Vit D?
Active?
25-OH D3
1,25-(OH)2 D3
Menkes disease CFs?
Brittle, kinky hair, growth retardation, hypotonia
Menke is KINKY
MMR defect results in what?
Works in what phase of cell cycle?
Lynch syndrome (HNPCC)
G2
CFs of OI?
pts can't BITE Bones - multiple fractures I (eye) - blue sclera Teeth - dental imperfections Ear - hearing loss
Niemann Pick disease deficient enzyme?
What accumulates?
CFs?
Sphingomyelinase
Sphingomyelin
Progressive neurodegeneration, HSM, foam cells, cherry red spot on macula
Urea cycle stages?
Ordinarily Careless Crappers Are Also Frivilous About Urination
What is a lipid laden macrophage resembling crumbled tissue paper called?
Gaucher cell
What disease is an example of Mosiacism?
Mutation in what?
CFs?
McCune-Albright syndrome
G-protein signaling
Cafe au lait, fibrous dysplasia, endocrinopathy (precocious puberty)
What causes severe CNS defects, intellectual disability and eventually death. It presents w/vomiting, poor feeding?
Tx?
Maple syrup disease
BCAAs + Thiamine
What causes asterixis (tremor)?
Does what?
How to tx underlying cause?
Hyperammonemia
Inhibits TCA cycle
Limit protein in diet
What is malnutrition not causing edema, results in muscle wasting due to a diet deficient in calories?
Marasmus
What syndrome causes decreased fertility, bronchiectasis, recurrent sinusitis, chronic ear infections, hearing loss and situs inversus?
Defect in what?
Kartagener’s syndrome (primary ciliary dyskinesia)
dynein
Build up of what substrate can shunt glucose and FFA towards production of ketone bodies?
Due to what being depleted?
Acetyl-CoA
Oxaloacetate
Marfan’s has what gene mutation?
What ch.?
FBN1
15
What cofactor is needed in the synthesis of heme, cystathinonine, niacin, histamine and neurotransmitters?
Vit B6 (pyridoxine)
Hydroxylation of collagen requires what amino acids?
What vitamin co factor?
lysine, proline
Vit C
McArdle disease deficient enzyme?
Cfs?
Skeletal m. Glycogen phosphorylase (Myophosphorylase)
Inc Glycogen in muscle but CANNOT break it down
Painful muscle cramps, myoglobinuria, arrhythmia
2nd wind phenomenon
What activates PDH complex?
INC NAD+
INC ADP
INC Ca
What is a different mutation in the same locus producing the same phenotype?
Ex?
Allelic heterogeneity
Beta-thalassemia
What disease is due to a defect in peroxisomes and causes hypotonia, seizures, HM, early death?
Zellweger
Renee zellweger sucks, proximately causes death
Vimentin is found in what tumors?
Mesenchymal
EndoMEtrial carcinoma
RCC
MEningioma
What is caused by a deficiency in ApoB48 and ApoB100?
What is absent?
Inheritance?
Abetalipoproteinemia
Chylomicrons, VLDL, LDL
AR
What are 3 uncoupling agents?
What do they do?
2,4-Dinitrophehnol, ASA, thermogenin
Produce heat
Deficiency of iduronidate sulfatase causes what?
Inheritance?
CF?
Hunter syndrome
X-linked recessive
Mild Hurler + aggressive behavior, no cornea involvement
What causes cystinuria?
Prevents reabsorption of what?
What is diagnostic?
Defect of renal PCT and intestinal a.a. Transporter
COLA - cysteine, ornithine, lysine, arginine
Urinary cyanide-nitroprusside test
ApoB100 contains what?
VLDL
IDL
HDL
Deficiency of what causes SCID?
Inheritance?
ADA
AR
Homocysteine —-> Cystathionine requires what enzyme?
What cofactor?
Deficiency results in what?
Cystationine synthase
B6
Homocystinuria
What ribosomal subunits found in prokaryotes?
30S + 50S –> 70S
ODD
Classic type of Ehlers-Danlos is what mutation?
Vascular type?
COL5A1 or COL5A2
Type 3 collagen
What is a complex 4 inhibitor of the ETC?
Complex 3?
Complex 1?
CO/CN-
antimycin (an3mycin)
Rotenone
B2 deficiency leads to what?
2 C’s
Cheilosis (fucked up lips)
Corneal vascularization
Has 2 ATP
PDH deficiency causes a build up of what?
Inheritance?
CFs?
Tx?
Lactate and alanine
X-linked
Neurologic defects, lactic acidosis
Lysine and Leucine - pureLy ketogenic a.a.’s
What does the urinary cyanide-nitroprusside test diagnose?
Inheritance?
Cystinuria
AR
What can precipitate G6PD?
Fava beans
Sulfonamides
primaquine
Anti-Tb drugs
Vit K is a cofactor for what?
Synthesized how?
Gamma-carboxylation of glutamic acid residues
Intestinal flora
What disease is due to a deficiency in neutral amino acid transporters in proximal renal tubular cells and causes pellagra-like symptoms?
Inheritance?
Tx?
Hartnup disease
AR
High-protein diet and nicotinic acid
What are the ketone bodies?
Urine test for ketones can detect what?
Acetone, acetoacetate, beta-hydroxybutyrate
ONLY acetoacetate
What are the 4 trinucleotide diseases w/their repeats?
Huntington’s - CAG
Myotonic Dystrophy - CTG
Fragile X - CGG
Friedreich ataxia - GAA
Menkes disease mutation?
Inheritance?
Decreased activity in what?
ATP7A
x-linked recessive
Lysyl oxidase
Wenicke-Korsakoff syndrome causes damage to what structures?
Medial dorsal nucleus of thalamus
Mammillary bodies
What causes osteogenesis imperfecta?
Inheritance?
Deficiency in COL1A1 or COL1A2
AD
What does the pentose phosphate pathway produce (HMP shunt)
NADPH
Fragile X syndrome mutation?
Inheritance?
CFs?
CGG trinucleotide repeat on FMR1 gene
X-linked dominant
long face w/long jaw, autism, giant gonads, MVP
Fabry disease deficient enzyme?
Accumulated substrate?
Inheritance?
CFs?
alpha-galactosidase A
Ceramics trihexoside
X-linked recessive
Peripheral neuropathy, angiokeratomas, hypohidrosis, late- Renal failure
FA degradation requires what special process?
What can inhibit it?
Carnitine shuttle
Malonyl-CoA
Homocysteine —> Methionine requires what enzyme?
What cofactor?
Deficiency results in what?
Methionine synthase
B12
Homocystinuria
What is the Cahill cycle?
Pyruvate —> alanine
ALT
Fructose intolerance is a hereditary deficiency of what?
Inheritance?
CFs?
Aldolase B
AR
Hypoglycemia, jaundice, cirrhosis, vomiting
What amino acids are needed for purine synthesis?
GAG
Glycine
Aspartate
Glutamine
Increased NADH/NAD+ ratio leads to production of what?
Decreased what?
Lactate - lactic acidosis
Malate - prevents gluconeogenesis –> fasting hypoglycemia
TCA
What syndrome shows microcephaly, intellectual disability, high-pitched crying or meowing, VSD?
Ch.?
Cri-du-chat syndrome
5
Phosphoenolpyruvate –> pyruvate via what enzyme?
Pyruvate –> acetyl coA via what enzyme?
What cofactor?
Pyruvate kinase
PDH, B1
Glucose —-> Sorbitol w/what enzyme?
Needs what cofactor?
Aldose reductase
NADPH
Where is LPL found?
What does Hepatic Lipase degrade?
Vascular endothelial surface
TGs remaining in IDL
Vit B7 used for what?
Deficiency how?
Carboxylation enzymes which add 1 carbon group
Antibiotics or eating raw egg whites
What inhibits de novo purine synthesis?
6-mercaptopurine
Azathioprine
What ribosomal subunits found in Eukaryotes?
40S + 60S –> 80S
EVEN
2nd-trimester quad screen showing Dec AFP, Dec estriol and Inc B-hCG and Inc inhibin A indicates what?
Down syndrome
What cell types are permanent (remain in G0)?
Neurons
Skeletal m.
Cardiac m.
Rbc’s
What causes maple syrup urine disease?
Inheritance?
Causes what in the blood?
Blocked degradation of Val, IsoLeu, Leu
AR
Increased alpha-ketoacids
Myotonic type 1 what is a mutation in what?
Inheritance?
CFs?
CTG trinucleotide repeat
AD
Cataracts, toupee (balding), Gonadal atrophy –> CTG
Vit K deficiency presents how?
neonatal hemorrhage w/INC PT and inc aPTTT
NORMAL bleeding time
Is PFK-2 or FBPase-2 active in the fed state?
What is decreased/increased?
Result?
PFK-2
Inc insulin, Dec cAMP, PKA
Less gluconeogenesis
Metachromatic luekodystrophy deficient enzyme?
What accumulates?
CFs?
Arylsulfatase A
Cerebroside sulfate
Central and peripheral demyelination w/ataxia, dementia
What causes alkaptonuria?
Messes up what pathway?
Inheritance?
Homogentisate oxidase deficiency
Degradation pathway of Tyrosine to fumarate
AR
What nucleotide has a methyl group?
THYmine
G6PD means you are not producing what?
Inheritance?
CFs?
NADPH
X-linked
Infection producing hemolysis
Lack of B12 leads to degeneration of what anatomical structures?
Dorsal columns
LCST
Spinocerebellar tracts
What is Vitamin B2 called?
B5?
B9?
Riboflavin: FAD, FMN
Pantothenic acid: CoA
Folate
Vitamin C is needed for synthesis of what?
Is an ancillary tx for what?
Hydroxylation of collagen synthesis
Dopamine B-hydroxylase
Methemoglobinemia by reducing Fe3+ to Fe2+
What does the TCA cycle produce?
3 NADH 1 FADH2 2 CO2 1 GTP Per acetyl-CoA = 10 ATP, 2x everything for glucose
Pompe disease what deficient enzyme?
Cfs?
Lysosomal acid alpha-1,4-glucosidase (acid maltase)
Cardiomegaly, HOCM, hypotonia, exercise intolerance –> early death
Prader-Willi syndrome is a result of what defect?
Sx?
Imprinting - paternal gene is deleted
Hyperphagia, obesity, intellectual disability, hypogonadism, hypotonia
Vit B5 is needed for what?
Def. causes what?
Coenzyme A, FA synthesis
Dermatitis, enteritis, alopecia, AI
What inhibits thymidylate synthase?
5-FU
PDH complex requires which 5 cofactors?
The Lovely Co-enzymes For Nerds Thiamine Lipoic acid CoA (B5) FAD (B2) NAD+ (B3)
Edwards syndrome has what CFs?
PRINCE Edward Prominent occiput Rocker-bottom feet Intellectual disability Nondisjunction Clenched fists Low-set ears
Vit B6 is a cofactor for what major reactions?
Can cause what conditions?
Transamination (ALT/AST), decarboxylation, glycogen phosphorylase
Sideroblastic anemia
Where is hexokinase located?
Glucokinase?
Which is induced by insulin?
Most tissues
Liver, B cells of pancreas
Glucokinase
What inhibits IMP dehydrogenase?
Mycophenolate
Ribavirin
What does HSL degrade?
TGs stored in adipocytes
What causes a musty body odor?
Disorder of what?
Inheritance?
PKU
Aromatic a.a. Metabolism
AR