Protein Turnover and Amino Acid Catabolism

These flashcards cover key terms and concepts related to protein turnover and amino acid catabolism, highlighting definitions essential for understanding the topic.

Proteins

Large biomolecules made up of amino acids, essential for various cellular functions.

Proteolytic enzymes

Enzymes that break down proteins into smaller peptides or amino acids.

Essential amino acids

Amino acids that cannot be synthesized by the body and must be obtained from the diet.

Peptidase

An enzyme that catalyzes the hydrolysis of peptides into amino acids.

Ubiquitin

A small protein that tags other proteins for degradation in the proteasome.

Aminotransferases

Enzymes that catalyze the transfer of an amino group from an amino acid to an α-keto acid.

Degron

A specific sequence of amino acids that signals a protein for degradation.

Carbamoyl phosphate synthetase I

Enzyme that catalyzes the first step of the urea cycle, forming carbamoyl phosphate from ammonia and bicarbonate.

Ketogenic amino acids

Amino acids that can be converted into ketone bodies or fatty acids.

Glucogenic amino acids

Amino acids that can be converted into glucose or intermediates of the citric acid cycle.

Phenylketonuria

A metabolic disorder caused by a deficiency of phenylalanine hydroxylase, leading to cognitive disabilities.

Branched-chain ketoaciduria

A disorder characterized by the inability to degrade branched-chain amino acids, leading to cognitive and physical impairments.

Proteins degradation

The process by which proteins are broken down into amino acids, often regulated by ubiquitin.

Half-life of proteins

The time it takes for half of the molecules of a protein to be degraded.

Urea cycle

A series of biochemical reactions that convert ammonia into urea for excretion.