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Electron microscopic study of the effects of antimicrobial agents on the cellular architecture of Leptospira


Morphological changes of Leptospira induced by ampicillin, streptomycin, or ciprofloxacin were studied by transmission electron microscopy after staining with uranyl acetate. Irregularities in coiling, loss of hooks, spherical swellings, membrane vesicle formation, disruption of outer membrane, exposure and detachment of flagella, penetration of dye, and lysis of cells were observed. These changes appeared in a time-dependent manner and appeared to be associated with the sites of action of antimicrobial agents. This is the first report delineating the action of aminoglycoside and new quinolone on the morphology of Leptospira cells.

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This work was supported by grants from the Special Coordination Funds on Science and Technology from the Ministry of Education, Sports, Culture, Science and Technology (MEXT) of Japan, and from the Science and Technology Research Partnership for Sustainable Development (SATREPS) of Japan Science and Technology Agency (JST). We are grateful to Professor Emeritus Kazunobu Amako for his comments and suggestions regarding the electron microscopy figures.

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Correspondence to Antara Chakraborty.

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Chakraborty, A., Takade, A., Villanueva, S.Y.A.M. et al. Electron microscopic study of the effects of antimicrobial agents on the cellular architecture of Leptospira . J Infect Chemother 17, 872–875 (2011).

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  • Leptospira
  • Antimicrobial agents
  • Cellular architecture
  • Electron microscopy