Gosset Molecular Classification
Enzyme, Ligase
Disease Roles
Argininosuccinate Synthase 1 Overview
Argininosuccinate synthase 1 (ASS1) is an enzyme that catalyzes the third step in the urea cycle, converting citrulline and aspartate to argininosuccinic acid. This reaction is crucial for detoxifying ammonia and synthesizing arginine. Mutations in ASS1 cause Citrullinemia Type I, leading to hyperammonemia. In cancer, reduced ASS1 expression results in arginine auxotrophy, making tumor cells vulnerable to arginine-depleting therapies. ASS1 expression can also influence chemotherapy resistance.
Mechanism of Action
Pegargiminase: Systemic arginine depletion Decitabine: Restores ASS1 expression through demethylation
Biological Functions
Urea cycle
Arginine biosynthesis
Nitric oxide synthesis
Polyamine synthesis
Creatine synthesis
Ammonia detoxification
Disease Associations
Citrullinemia Type I
Cancer
Safety Considerations
- Hyperammonemia in Citrullinemia Type I
- Potential resistance to chemotherapy in cancer
- Arginine auxotrophy in cancer cells
Interacting Drugs
Pegargiminase
Decitabine
Associated Biomarkers
| Biomarker |
|---|
| ASS1 expression level in tumors |