Azaserine

Azaserine is a naturally occurring diazo-containing amino acid derivative that functions as a potent glutamine antagonist and antimetabolite (PubChem CID 11537). It was originally isolated from cultures of Streptomyces and has been extensively studied for its antibiotic and antineoplastic properties (Wikipedia). Azaserine acts by irreversibly inhibiting several enzymes that utilize glutamine as a nitrogen donor, most notably phosphoribosylformylglycinamidine synthase (PFAS) and amidophosphoribosyltransferase (PPAT) in the de novo purine biosynthetic pathway (DrugBank DB02443). By blocking these enzymes, it disrupts the synthesis of DNA and RNA, leading to cell cycle arrest and apoptosis in rapidly dividing cells (PubMed PMID: 15657037). Beyond its role in oncology, azaserine is frequently used in metabolic research to inhibit the hexosamine biosynthetic pathway, helping to elucidate the mechanisms of insulin resistance and glucose-induced vascular damage (PubMed PMID: 11078440). However, its clinical utility is severely limited by significant toxicity, including potent mutagenic and carcinogenic effects observed in animal models (NTP Technical Report). It is primarily used today as a biochemical tool rather than a therapeutic agent due to these safety concerns.

Other names

O-diazoacetyl-L-serineL-AzaserineDiazoacetylserineCI-64CN-15,757

Azaserine acts as a structural analog of glutamine, irreversibly inhibiting glutamine-dependent amidotransferases such as phosphoribosylformylglycinamidine synthase (PFAS) and amidophosphoribosyltransferase (PPAT) by covalently binding to their active sites (DrugBank DB02443).