Biochem Flashcards
(28 cards)
Hartnup Disease
Absence of AA transporter –> loss of tryptophan in urine
Symptoms of niacin deficiency: pellagra (hyperpigmentation on sun-exposed skin) and neurological symptoms
Branched-chain AAs
Valine, Leucine, Isoleucine
Maple syrup urine disease
Deficient alpha ketoacid dehydrogenase
Leads to sweet smelling urine and neurotoxicity
Peroxisomes
Oxidate very long and branched chain fatty acids
Proteasomes
Degradation of ubiquitinated proteins
Rate limiting step in fatty acid synthesis
Acetyl-CoA –> Malonyl-CoA
Enzyme: Acetyl-CoA carboxylase
Requires: CO2 and Biotin (B7)
Biotin
Vit B7
Important for carboxylation enzymes
Enzyme that pulls triglycerides out of adipose tissue to release fatty acids from glycerol backbone
Hormone Sensitive Lipase
Responds to glucagon
Carnitine shuttle
Moves fatty acyl CoA –> mitochondria matrix
Binds with carnitine (CPT1) –> acyl carnitine (moves to matrix) –> converted back to fatty acyl CoA (CPT2)
Hypoketotic Hypoglycemia
Due to carnitine deficiency
Will have low acylcarnitine
MCAD deficiency (Medium Chain Fatty Acetyl-CoA Dehydrogenase)
Hypoglycemia without ketones
High acycarnitine levels
Most common urea cycle disorder
Ornithine transcarbamylase deficiency
Increased carbamoyl phosphate, orotic acid, and ammonia
Vit B1 other name
Associated enzymes
Associated disorders
Thiamine
Cofactor for dehydrogenase enzymes and transketolase
Beriberi (neuritis, tachycardia, edema), Wernicke-Korsakoff
Vit B2 other name
Purpose
Riboflavin
Generate FAD and FADH2
Vit B3 other name
Purpose
Associated disorders
Niacin (Can also be synthesized from tryptophan B6)
Produce NAD and NADH
Pellagra (dermatitis, diarrhea, dementia, death)
Carcinoid syndrome, Hartnup disease
Vit B6 other name
Purpose
Associated disorders
Pyridoxal phosphate
Aminotransferase reactions, neurotransmitters, synthesize niacin and ALA (heme)
Sideroblastic anemia, isoniazid use, CNS + pellagra
Vit B7 other name
Associated enzymes
Associated disorders
Biotin
Carboxylase enzymes
Deficient with ingestion of raw egg whites
Vit B9 and B12 other names
Purpose
Associated disorders
Folate and cobalamin
Thymidine and methionine synthesis (B12 odd chain fatty acid metabolism)
Megaloblastic anemia
Vit A other name
Functions
Deficiency symptoms
Retinol
Important for eyes and skin
Night blindness, dry skin, growth failure
What is used to convert Fe3+ iron –> Fe2+ iorn
Vit C (Ascorbic acid)
Phenylalanine –> tyrosine requires
BH4
Dihyropterine reductase
NADH
PKU
Deficiency of phenylalanine hydroxylase or BH4 (will also have dopamine and serotonin issues)
Musty smell in urine, CNS symptoms, and pale skin/eyes
Babies with high alanine
Mitochondrial disorders
Ornithine transcarbamylase deficiency
Hyperammonemia
High carbamoyl phosphate
High orotic acid
