The effect of pentachlorophenol and its metabolite tetrachlorohydroquinone on RNA, protein, and ribosome synthesis in Saccharomyces cells.

The effect of pentachlorophenol (PCP) and its metabolite tetrachlorohydroquinone (TCH) were tested on growth, RNA, protein and ribosome syntheses, and ribosome content in yeast cells. Cells exposed to increasing concentrations of PCP show increasing inhibition to RNA and ribosome synthesis, and to cell growth. TCH causes a delay of the growth of the cell culture (prolongation of the lag phase) but does not cause inhibition. After treatment with TCH the maximum of the RNA synthesis was retarded, but subsequently reached nearly the same level as the untreated control cells. On ribosome synthesis and ribosome content, treatment with increasing concentrations of PCP, as well as of TCH, leads to a substantial decrease in ribosomal synthesis and, finally, total inhibition. Parallel to this, the content of free and membrane-bound ribosomes is diminished. PCP exhibits a stronger effect than TCH. The protein synthesis is only slightly reduced after treatment with PCP or TCH (with concentrations up to 20 micrograms/ml).