Penguraian Parasetamol oleh Sel dan Protein Ekstraselular Khamir Candida tropicalis dan Rhodotorula minuta

Yeast can be used as cell model to study toxicity in mammalian cell. In the previous study we demonstrated that yeast Candida tropicalis was able to metabolize analgesic drug paracetamol causing oxidative stress. This phenomenon is similar to that in mammalian cell. In mammalian cell system, enzymes responsible in paracetamol metabolism are at least cytochrome P450 (P450) and peroxidase. In order to understand the possible role of peroxidase enzyme in paracetamol metabolism in yeast, research on the effect of peroxidase inhibitor of sodium cyanide (KCN) and a peroxidase substrate peroxide (H2O2) on paracetamol degradation by cell suspension and extracellular protein of C. tropicalis and Rhodotorula minuta was carried out. Paracetamol was degraded by cells or extracellular protein in both of yeast. Paracetamol degradations were significantly inhibited by KCN (0.01 μM) or H2O2 (3 μM). Since P450 is generally located inside the cell (in cell membrane) while no activity of P450 in extracellular, the data indicated the presence of soluble enzyme which is able to metabolize paracetamol that is inhibited by KCN or H2O2. The possibility of presence of peroxidase in the soluble protein by which paracetamol is metabolized and its inhibition by peroxide via competitive substrate or peroxide toxicity is discussed. The results supported use of yeast for studying toxicity of paracetamol in cell level. Media Litbangkes, Vol. 27, No. 3. Hal. 169-174