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UAMS Biochemistry exam 3
Basic Structure of Amino Acids(AA) At least one of both amino(H2H) and carboxylic(COOH)
functional group
Polypeptide chain of amino acids
Large polypeptide protein
Essential Amino Acids(PVT) Phenylalanine, valine, theronine
Essential Amino Acids(TIM) Tryptophan, isoleucine, methionine
Essential Amino Acids(HALL) Histidine, argnine, leucine, lyside
Phenylketonuria(PKU) -Autosomal recessive, 1:15,000
-Absence of phenylalanine hydrolase(PAH)
-PAH coverts phenylalanine—>tyrosine
-Can lead to significant and permanent brain damage
Phenylketonuria(PKU) test methods -Guthrie test- old semi-quantitative bacterial inhibition
assay
-Replaces with HPLC, MS/MS and micro fluormetric assay for phenylalanine on dried blood
filter discs
Phenylketonuria(PKU) results Increased phenylalanine and decreased tyrosine
Tyrosinemia inherited disorders of tyrosine metabolism can result in three types of tyrosinemia,
each caused by deficiency of a different enzyme
Tyrosinemia type I 1:100,000, liver/kidney failure, CNS issues, mutation in
fumarylacetoacetate hydrolase(FAH)
Tyrosinemia type II 1:250,000
Tyrosinemia type III Very rare
Tyrosinemia results Increased blood tyrosine and succinylacetone
Alkaptonuria -Inherited autosomal recessive, 1:250,000
-Deficiency in homogentistate oxidase(HGD)
-Elevated homogentistic acid
-Brown urine if exposed to air
Alkaptonuria test method Ferric chloride is a rapid test, turns urine black
, 2
Maple Syrup Urine Disease(MSUD) -Absence of branched chain alpha-keto acid
decarboylase(BCKD)
-Inhibits metabolism of leucine, isoleucine and valine
-1:185,000
-Possible brain injury, muscle rigidity and respiratory irregularities
-
Maple Syrup Urine Disease(MSUD) test methods Modified Guthrie test, micro fluorometric
assay or DNA mutation detection assay
Homocystinuria -Autosomal recessive 1:200,000
-MTHFR mutation
-Deficiency in enzyme cystathionine beta-synthase, needed for metabolism of methionine
Homocytinuria test methods -Screen with modified Guthrie
-Confirm with HPLC/MS-MS
Cystinuria -Autosomal recessive 1:10,000
-Mutation in SLC3A1/SLL7A9
-Mutation causes inadequate reabsorption of cystine in kidney
-Cystine can precipitate out of urine by the form of stone
Cystinuria test method Urine + cyanice nitroprusside
isoelectric point Point at which a compound is electrically neutral.
Prealbumin -Migrates ahead of albumin in classic electrophoresis of proteins
-Critical to transport retinol(vitamin A)
Decrease in prealbumin? Nutritional deficiency, liver damage
Increase in prealbumin? Alcohol abuse, steroid therapy or chronic renal failure
Albumin -3.5-5.5
-Binds and transports various substances in blood
Decrease in albumin? Acute inflammatory response, liver and kidney damage,
malnutrition/absorption
Increase in albumin? -Dehydration
alpha 1 antitrypsin -inhibition of protease neutrophil elastase(DNE)
UAMS Biochemistry exam 3
Basic Structure of Amino Acids(AA) At least one of both amino(H2H) and carboxylic(COOH)
functional group
Polypeptide chain of amino acids
Large polypeptide protein
Essential Amino Acids(PVT) Phenylalanine, valine, theronine
Essential Amino Acids(TIM) Tryptophan, isoleucine, methionine
Essential Amino Acids(HALL) Histidine, argnine, leucine, lyside
Phenylketonuria(PKU) -Autosomal recessive, 1:15,000
-Absence of phenylalanine hydrolase(PAH)
-PAH coverts phenylalanine—>tyrosine
-Can lead to significant and permanent brain damage
Phenylketonuria(PKU) test methods -Guthrie test- old semi-quantitative bacterial inhibition
assay
-Replaces with HPLC, MS/MS and micro fluormetric assay for phenylalanine on dried blood
filter discs
Phenylketonuria(PKU) results Increased phenylalanine and decreased tyrosine
Tyrosinemia inherited disorders of tyrosine metabolism can result in three types of tyrosinemia,
each caused by deficiency of a different enzyme
Tyrosinemia type I 1:100,000, liver/kidney failure, CNS issues, mutation in
fumarylacetoacetate hydrolase(FAH)
Tyrosinemia type II 1:250,000
Tyrosinemia type III Very rare
Tyrosinemia results Increased blood tyrosine and succinylacetone
Alkaptonuria -Inherited autosomal recessive, 1:250,000
-Deficiency in homogentistate oxidase(HGD)
-Elevated homogentistic acid
-Brown urine if exposed to air
Alkaptonuria test method Ferric chloride is a rapid test, turns urine black
, 2
Maple Syrup Urine Disease(MSUD) -Absence of branched chain alpha-keto acid
decarboylase(BCKD)
-Inhibits metabolism of leucine, isoleucine and valine
-1:185,000
-Possible brain injury, muscle rigidity and respiratory irregularities
-
Maple Syrup Urine Disease(MSUD) test methods Modified Guthrie test, micro fluorometric
assay or DNA mutation detection assay
Homocystinuria -Autosomal recessive 1:200,000
-MTHFR mutation
-Deficiency in enzyme cystathionine beta-synthase, needed for metabolism of methionine
Homocytinuria test methods -Screen with modified Guthrie
-Confirm with HPLC/MS-MS
Cystinuria -Autosomal recessive 1:10,000
-Mutation in SLC3A1/SLL7A9
-Mutation causes inadequate reabsorption of cystine in kidney
-Cystine can precipitate out of urine by the form of stone
Cystinuria test method Urine + cyanice nitroprusside
isoelectric point Point at which a compound is electrically neutral.
Prealbumin -Migrates ahead of albumin in classic electrophoresis of proteins
-Critical to transport retinol(vitamin A)
Decrease in prealbumin? Nutritional deficiency, liver damage
Increase in prealbumin? Alcohol abuse, steroid therapy or chronic renal failure
Albumin -3.5-5.5
-Binds and transports various substances in blood
Decrease in albumin? Acute inflammatory response, liver and kidney damage,
malnutrition/absorption
Increase in albumin? -Dehydration
alpha 1 antitrypsin -inhibition of protease neutrophil elastase(DNE)