Amino Acid Disorders, Urea Cycle, and Peroxisomal Fatty Acid Oxidation Flashcards

Fill-in-the-blank flashcards covering key topics from the lecture notes on fatty acid oxidation disorders, peroxisomal disorders, urea cycle defects, and common amino acid disorders.

The enzyme responsible for transporting long-chain fatty acids into mitochondria for beta-oxidation is __.

CPT-I

The enzyme that converts acyl-carnitine to acyl-CoA inside the mitochondrial matrix in long-chain fatty acid beta-oxidation is __.

CPT-II

A peroxisomal biogenesis disorder characterized by defective peroxisomes and affecting multiple organs, often including the brain and liver, is __.

Zellweger syndrome

X-linked recessive disorder of fatty acid oxidation due to defective transport of very long-chain fatty acids (VLCFA) across the peroxisomal membrane is __.

X-linked adrenoleukodystrophy

Deficiency of phytanoyl-CoA hydroxylase leading to accumulation of phytanic acid is due to mutations in __.

PHYH

An autosomal recessive alpha-oxidation disorder causing accumulation of phytanic acid is __.

Refsum disease

The urea cycle disorder that is X-linked recessive and presents with hyperammonemia, increased glutamine, decreased BUN, and orotic aciduria is __.

Ornithine transcarbamylase (OTC) deficiency

The urea cycle disorder characterized by hyperammonemia with increased glutamine and no orotic aciduria is __.

Carbamoyl phosphate synthetase I (CPSI) deficiency

A defect in the urea cycle causing accumulation of ammonia and citrulline, and considered the second most common defect, is __.

Argininosuccinate synthetase deficiency

A urea cycle disorder that leads to accumulation of arginine in the blood is __.

Arginase deficiency

Phenylketonuria (PKU) is caused by deficiency of __.

Phenylalanine hydroxylase (PAH)

Alkaptonuria results from deficiency of __.

Homogentisate oxidase

Albinism can result from deficiency of the enzyme __.

Tyrosinase

Homocystinuria is an autosomal recessive disorder due to accumulation of __.

Homocysteine

Maple syrup urine disease results from defective branched-chain ketoacid dehydrogenase, causing accumulation of __.

Branched-chain amino acids (valine, leucine, isoleucine)

Methylmalonic aciduria arises from deficiency of methylmalonyl-CoA mutase that converts methylmalonyl-CoA to __.

Succinyl-CoA

Argininosuccinate lyase deficiency leads to accumulation of __ affecting the urea cycle.

Argininosuccinate