Protein Metabolism

Protein Metabolism

The biochemical process by which proteins are synthesized, broken down, and utilized in the body.

Transamination

The process of transferring an amino group from one amino acid to a keto acid, forming a new amino acid (non-essential).

Deamination

The removal of an amino group from an amino acid, resulting in the production of ammonia and a keto acid.

Urea Cycle

A series of biochemical reactions in the liver that convert ammonia to urea for excretion, preventing toxic accumulation.

prevent toxic accumulation of ammonia

main function of urea cycle

Transaminases

Enzymes that catalyze the transfer of amino groups in transamination reactions; important for amino acid metabolism.

Alanine/aspartate Aminotransferase (ALT/AST)

enzymes involved in protein metabolism which elevated levels indicate liver damage or disease.

alanine aminotransferase (ALT)

enzyme found mostly in liver indicator for acute hepatitis

Blood Urea Nitrogen (BUN) Test

A blood test that measures the amount of urea nitrogen in the blood, is used to assess kidney function/damage and effectiveness of dialysis.

Citrullinemia

A genetic disorder affecting the urea cycle, leading to elevated levels of citrulline and ammonia in the blood.

ornithine transcarbamylase (OTC)

most common urea cycle defect

mutation of argininosuccicate synthetase I (ASS1) that affects the urea cycle

what causes citrullinemia

Phenylketonuria (PKU)

phenylalanine/tyrosine metabolism disease leading to intellectual disability, microcephaly, decreased skin/ hair pigmentation, and musty order.

Oculocutaneous Albinism

tyrosine metabolism disease characterized by a lack of melanin pigmentation in the skin, hair, and eyes

anesthesia with epinephrine

what to avoid in patients with urea cycle disorder and fasting

Alkaptonuria

tyrosine metabolism disease resulting in dark urine and pigmented sclera due to the accumulation of homogentisic acid.

Cystinuria

cystine metabolism disorder characterized by excessive urinary excretion of cysteine, leading to kidney stones.

Homocystinuria

methionine metabolic disorder characterized by myopia, Marfan-like skeletal changes, DVT, intellectual disability, and scoliosis.

Maple Syrup Urine Disease

isoleucine, leucine, and valine associated metabolic disorder characterized by intellectual disability, ketosis, and seizures.

Heme Metabolism

The biochemical process involving the synthesis and breakdown of heme, a component of hemoglobin.

Lead Poisoning

A condition affecting heme synthesis leading to symptoms such as irritability, developmental delay, and anemia.

ALA dehydratase, ferrochelatase (heme synthase)

enzyme inhibited by lead

vitamin b deficinecy, lead poisoning, iron deficiency

heme associated diseases

EDTA chelation therapy, bowel irrigation

treatment of lead poisoning

Bilirubin

A yellow compound produced during the breakdown of red blood cells; excessive levels can lead to jaundice.

Jaundice

A condition characterized by yellowing of the skin and eyes due to high levels of bilirubin in the blood.

Kernicterus

A severe form of jaundice in newborns that can lead to brain damage, cerebral palsy, hearing loss, intellectual disability and staining of primary teeth

phototherapy, IV Ig, exchange transfusion

treatment of jaundice

lead poisoning

what might be the cause of severe anemia in an individual with an adequate diet and developmental delay

billi rubin

what is not being processed properly is an individual has yellow green stained teeth

alkaptonuria and tyrosine

what is the disorder and amino acid affected of a patient with blue pigmentation of the sclera of their eyes and dark urine