Pore Formation on Proliferating Yeast Saccharomyces cerevisiae Cell Buds by HM-1 Killer Toxin
| Autor: | Takahide Watanabe, Hiroshi Urakami, Tatsuo Ohta, Tsuyoshi Takasuka, Yasuhiro Furuichi, Tadazumi Komiyama, Misako Satoh, Yasuhiko Shiratori |
|---|---|
| Rok vydání: | 1996 |
| Předmět: |
Programmed cell death
Time Factors Cell Saccharomyces cerevisiae Antifungal drug Sodium Chloride Biology Biochemistry Pichia Cell wall Osmotic Pressure medicine Sorbitol Molecular Biology Budding Cell Membrane Temperature General Medicine Mycotoxins biology.organism_classification Killer Factors Yeast Yeast Cell biology Viable Cell Count medicine.anatomical_structure Isotonic Solutions Cell Division |
| Zdroj: | Journal of Biochemistry. 119:731-736 |
| ISSN: | 0021-924X |
| Popis: | The cytocidal effect of HM-1 produced by Hansenula mrakii on yeast Saccharomyces cerevisiae cells was studied. The HM-1 strongly inhibited the growth of S. cerevisiae cells at a low concentration (IC50: 2.1 x 10(-8) M) by reducing the number of viable cells. The killer action of HM-1 was most efficient when cells were actively proliferating. Cells in a resting state were resistant, but they became HM-1-sensitive after about 90 min of culturing at 30 degrees C, concomitantly with the increment of budding index. In association with the reduction of viable cell number, ultraviolet light-absorbing cellular components were discharged from sensitive cells. HM-1 molecules appear to bind to susceptible cells rather loosely since cells incubated with HM-1 were able to proliferate after having been washed. By phase-contrast light microscopy and scanning electron microscopy, discharge of cell material was observed at the budding portions of HM-1-treated cells. Addition of sorbitol to make the culture medium isotonic partially reduced the cell death induced by HM-1. These results suggest that HM-1 acts on the budding region of proliferating yeast cells, resulting in pore formation, leakage of cell material and eventual cell death. |
| Databáze: | OpenAIRE |
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