Biochemistry 2- Boards & Beyond Flashcards
What amino acids do histones have a high content of
Lysine, arginine
What substitution occurs with sickle cell anemia
Polar glutamate for nonpolar valine
What are the 2 strictly ketogenic amino acids
Leucine, lysine
What is the cofactor for phenylalanine hydroxylase
BH4 (tetrahydrobiopterin)
What is the order of tyrosine metabolism
Tyrosine, DOPA, dopamine, norepinephrine, epinephrine
What enzyme is deficiency in oculocutaneous albinism
Tyrosinase
What is deficient in alkaptonuria
Homogentisic acid oxidase
What is the classic findings with alkaptonuria
Dark urine when left standing, arthritis, black pigment in cartilage/joints (calcification in IV discs), urine discoloration in children, dark pigment
What are common serotonin effects in carcinoid syndrome
Diarrhea (serotonin stimulates GI motility), increased fibroblast growth and fibrogenesis (leading to valvular lesions), flushing
What is the issue with Hartnup disease and how is it inherited
Absence of AA transport in proximal tubule; autosomal recessive
What are some common symptoms with Hartnu disease
Pellets (hyperpigmented rash, exposed areas of skin, red tongue, diarrhea, dementia)
What are the branched chain Amino acids
Valine, leucine, isoleucine
What is the deficiency in maple syrup urine disease and what are some symptoms
Deficiency of alpha keto acid dehydrogenase; increased branched chain AAs and alpha-ketoacids in plasma; neurotoxicity is main problem, urine smells sweet
What are some common symptoms of homocystinuria
Lens dislocation, long limbs, chest deformities, osteoporosis in childhood, blood clots, early atherosclerosis
What is the alanine cycle used fr
By the muscles to transfer nitrogen to liver
What is the rate limiting enzyme in the urea cycle
Carbamoyl phosphate synthetase I
What is the most common defect in urea cycle
Ornithine transcarbamylase
What is another name for vitamin B1
Thiamine
What is the term for thiamine deficiency not associated with alcohol and how does it present
Beriberi; dry has polyneuritis, muscle weakness; wet has tachycardia, high-output heart failure, edema
What is another name for vitamin B2
Riboflavin