Harper's Biochemistry Chapter 29 - Catabolism of the Carbon Skeletons of Amino Acids

The breakdown of methionine into propionyl-CoA.

The breakdown of branched-chain amino acids into smaller molecules, analogous to fatty acid catabolism.

An intermediate molecule formed during leucine catabolism.

An intermediate molecule formed during isoleucine catabolism.

An intermediate molecule formed during valine catabolism.

A genetic disorder impacting the alpha-ketoacid decarboxylase complex, causing a build-up of branched-chain amino acids.

A complex of enzymes crucial for breaking down branched-chain amino acids.

The breakdown of amino acids (building blocks of proteins) to be used for energy or to synthesize other molecules.

The breakdown of leucine, isoleucine, and valine into smaller molecules. This process is similar to breaking down fatty acids.

Inherited metabolic disorders where the breakdown of proline is impaired, leading to elevated levels of proline in the blood.

Inherited metabolic disorder affecting arginine metabolism, leading to elevated arginine levels.

A multi-enzyme complex that breaks down the molecule created from branched-chain amino acids after transamination step.

The different ways the products of amino acid breakdown are used by the body (e.g., energy production, synthesis of other molecules).

A reaction that transfers an amino group from an amino acid to a keto acid, forming a new amino acid and a new keto acid.

A multi-enzyme complex in mitochondria that breaks down glycine into CO2, NH4+, and N5,N10-methylenetetrahydrofolate.

A product of tryptophan breakdown.

The breakdown of phenylalanine, a pathway that's largely similar across the breakdown of several branched-chain amino acids.

A condition where the body lacks folate (a B vitamin), which impairs the transfer of the formimino group in amino acid metabolism.

A molecule, often vitamin B derived, that helps aminotransferases catalyze reactions.

Deficiency of vitamin B6

Amino acids with branched carbon chains (e.g., leucine, isoleucine, valine).

Inherited problems in the processing of histidine, which can lead to histidinemia or urocanic aciduria.

A condition affecting intestinal and renal transport of tryptophan and other neutral amino acids, leading to their excretion.

Elevated excretion of formiminoglutamate(FIGLU) following a histidine load is a diagnostic indicator of folate deficiency.

Disorders related to abnormal amino acid metabolism and excretion in urine.

Genetic disorders affecting specific enzymes in the catabolic pathways of amino acids, leading to specific clinical issues.

An active form of methionine, produced via a reaction with ATP, which is instrumental in certain biochemical reactions.

A molecule formed during the breakdown of methionine, which proceeds through reactions 2, 3, and 4 of Figure 19-2.

Observable effects of the build-up of different metabolites caused by faulty enzymes in a metabolic pathway.

A screening tool to detect metabolic defects in newborns by analyzing the breakdown products in a blood sample.

The breakdown of amino acids into molecules that can be used for energy or to build other molecules.

Genetic disorders that impair specific enzymes involved in amino acid breakdown, causing buildup of harmful metabolites.

Observable effects, such as brain damage, caused by the buildup of harmful metabolites due to faulty enzymes.

Diagnosis of a condition or disorder before birth.

Changes in DNA affecting enzyme production or function, often leading to metabolic diseases.

Ways the products of amino acid breakdown are utilized, such as energy production or synthesis of other molecules.

Accumulation of substances that result from a disrupted metabolic pathway.

The ability of an enzyme to catalyze a biochemical reaction.

The three-dimensional arrangement of an enzyme's components, influencing its function.

Disorders arising from defects in metabolic pathways, often concerning amino acid breakdown, resulting in specific clinical issues.

Reduced catalytic activity of a mutated enzyme, which impairs the speed at which it completes chemical tasks.

The breakdown of amino acids for energy or synthesis of other molecules

Genetic disorders impairing amino acid breakdown, resulting in harmful metabolites.

Observable effects of a buildup of harmful metabolites.

Changes in DNA affecting enzyme production or function.

Diagnosis of a condition or disorder before birth.

How products of amino acid breakdown are used.

Accumulation of substances due to disrupted metabolic pathways

Enzyme's ability to catalyze biochemical reactions.

An enzyme's 3D arrangement of components; crucial for function.

Disorders stemming from defects in metabolic pathways, esp. amino acid breakdown.

Reduced catalytic activity of mutated enzyme, slowing process.

The initial catabolic reaction for most amino acids; involves transferring an amino group to an alpha-keto acid to produce another amino acid and a new keto acid.

The breakdown of amino acids, often for energy or to synthesize other molecules.

An enzyme catalyzing transamination reactions.

A common acceptor of amino groups in transamination reactions.

The breakdown pathway for proline, occurring in the mitochondria.

Inherited disorders affecting proline breakdown, leading to elevated proline levels.

A molecule that can be used in both catabolic and anabolic pathways.

A rare genetic disorder where glycine accumulates in body tissues, including the nervous system, due to an impaired glycine degradation pathway.

A genetic defect preventing the breakdown of glyoxylate, leading to oxalates buildup, causing kidney stones (urolithiasis), kidney damage (nephrocalcinosis), and early death.

A condition where glycine is not reabsorbed by the kidneys, leading to its excretion in urine.

The process of breaking down glycine into simpler molecules.

An enzyme that converts serine into glycine.

The breakdown of amino acids for energy or to build other molecules.

How the products of amino acid breakdown are used (energy, molecule building).

Genetic problems in amino acid breakdown enzymes.

Observable effects of buildup of harmful breakdown products.

Treatment, often dietary, for impaired amino acid metabolism.

Techniques to permanently fix a metabolic defect.

Conversion of amino acids to carbs, fats, or both.

Amino acid breakdown intermediates create carbohydrates and lipids.

Amino acids that can be converted to fats.

Amino acids that can be converted to carbohydrates.

Amino acids that can form oxaloacetate.

Essential for preventing brain damage and early mortality in Maple Syrup Urine Disease (MSUD) by correcting dietary protein with an amino acid mixture.

Mutations in genes encoding E1α, E1β, E2, and E3 enzymes lead to different MSUD subtypes.

MSUD subtype caused by mutations in the E1α gene.

MSUD subtype caused by mutations in the E1β gene.

MSUD subtype caused by mutations in the E2 gene.

MSUD subtype caused by mutations in the E3 gene.

MSUD subtype where the α-ketoacid decarboxylase retains some activity, resulting in later-onset symptoms.

Metabolic disorder with elevated isovalerate due to impaired isovaleryl-CoA dehydrogenase enzyme activity.

Foods containing high levels of proteins, that cause a buildup of metabolites when processing amino acids in affected individuals.

The breakdown of tyrosine into simpler molecules, ultimately to acetyl-CoA

A metabolic disorder caused by a defect in fumarylacetoacetate hydrolase, leading to tyrosine accumulation and potential liver failure.

A test to detect elevated phenylalanine levels in newborns; increasingly done with tandem mass spectrometry.

An enzyme catalyzing the final step in the tyrosine catabolic pathway; its deficiency causes Type I tyrosinemia.

A powerful analytical technique used to screen for multiple metabolic disorders in newborns, including PKU.

Genetic disorders impairing specific enzymes in amino acid catabolic pathways.

Observable effects of the buildup of harmful metabolites due to enzyme deficiencies in metabolic pathways.

Restricting dietary phenylalanine intake to prevent mental retardation, without causing malnutrition, in patients with PKU.

A genetic disorder causing a deficiency in the enzyme phenylalanine hydroxylase, leading to phenylalanine buildup in the body.

Tryptophan is broken down via the kynurenine-anthranilate pathway, involving tryptophan oxygenase, an iron-porphyrin protein.

The enzyme responsible for converting phenylalanine to tyrosine. Defects in this enzyme cause PKU.

A diet low in phenylalanine is crucial for preventing mental retardation in individuals with PKU.

Diagnostic testing for metabolic defects like PKU before birth using DNA.