In Silico Characterization of c-Sarcin Ribotoxin from Aspergillus clavatus as a Potential Anticancer Agent

Cancer remains the leading cause of premature death in Indonesia, with approximately 147,500 deaths annually, underscoring the urgent need for more effective therapies. Ribotoxin c-sarcin from Aspergillus clavatus has demonstrated potential as a therapeutic agent by irreversibly inhibiting protein synthesis and inducing apoptosis in cancer cells. In this study, recombinant c-sarcin was successfully expressed in Komagataella phaffii using a methanol-induction system at 30°C, achieving a peak protein yield of 48,018 mg/L on day 6 of cultivation. Molecular docking analysis using α-sarcin as a structural model revealed a strong interaction with the sarcin/ricin loop of mouse 28S rRNA, with a binding energy of -1.531 kJ/mol. Key hydrogen bonds were formed by residues Lys29, Phe94, and Pro99. Phylogenetic analysis revealed 100% sequence identity to c-sarcin from Aspergillus clavatus, indicating its functional similarity. These quantitative findings support the therapeutic relevance of c-sarcin and underscore the role of bioinformatics in accelerating the discovery of novel anticancer agents.