Tubercidin (7-Deazaadenosine), an antibiotic isolated from Streptomyces tubercidicus, is a DNA/RNA Synthesis inhibitor. Tubercidin is a toxic adenosine analogue with antiviral, antitrypanosomal, and antifungal functions. It inhibits multiple metabolic processes, including RNA processing, nucleic acid synthesis, protein synthesis, and methylation of tRNA through intracellular incorporation into nucleic acids. Tubercidin acts as a plant antifungal, inhibits mammalian SAH hydrolase (SAHH), and blocks purine biosynthesis in Candida famata.