Summary
The effects of the new antibiotic netilmicin (NT) were studied onEuglena gracilis green cells. It was found that, in the presence of the drug, chlorophyll synthesis was strongly inhibited and plastid structure dramatically altered as revealed by fluorescence and electron microscopic observations. Importantly, NT at low concentrations (10–20 Μg/ml) and for short periods of time (36–72 hours) induced a marked bleaching effect that was permanent and accompanied by the persistence in the colorless cells of poorly differentiated plastids. Other cell components were not influenced as shown by their appearance and also by the kinetics of growth and the cell viability. On the basis of the results and of the literature on the bleaching agents it is suggested that NT is an untoxic antibiotic which specifically inhibits protein synthesis at prokaryotic level.
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This work was supported by a grant from Italian Research Council (CNR), Contract N. 82.02016.04.
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Fasulo, M.P., Bonora, A. Indications about the mechanism of action and toxicity of netilmicin on the basis of the antiplastidial activity inEuglena gracilis . Protoplasma 119, 31–34 (1984). https://doi.org/10.1007/BF01287814
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DOI: https://doi.org/10.1007/BF01287814