title: Inhibition of plastid division by ampicillin in the pteridophyte Selaginella nipponica Fr. et Sav.
abstract: We investigated the effect of the beta-lactam antibiotic, ampicillin, on plastid division in the pteridophyte Selaginella nipponica. Guard cells of plantlets treated with 1 mM ampicillin only often had one plastid, whereas guard cells of untreated plantlets had two to four plastids. We generated a S. nipponica cell culture system and used it to investigate the effects of ampicillin. Treatment with 1 mM ampicillin had no effect on cell division in culture. We classified cultured cells into four types based on the number of plastids they contained: one (Type I), two (Type II), three or four (Type III) and more than five (Type IV). After 3 d in culture, the percentage of each cell type (I-IV) was 29.5, 46.7, 20.9, and 1.9%, respectively. Subsequently, the percentage of Types III and IV increased gradually, reaching 61.9 and 11.4%, respectively, after 15 d in culture in the absence of ampicillin. When 1 mM ampicillin was added, there was a minimal increase in the number of Type III and IV cells, with high percentages of Type I and II cells (32.4 and 45.7%, respectively) after 15 d. These results suggest that ampicillin inhibits plastid division in S. nipponica.
authors.affiliation: Faculty of Education and Welfare Science, Oita University, Dannoharu, Oita, 870-1192 Japan. yizumi@cc.oita-u.ac.jp
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Izumi
authors.forename: Kanji
authors.initials: K
authors.lastname: Ono
authors.forename: Hiroyoshi
authors.initials: H
authors.lastname: Takano
mesh_terms: D000667:Ampicillin / Q000494:pharmacology*; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D002455:Cell Division / Q000187:drug effects; D002478:Cells, Cultured; D008856:Microscopy, Fluorescence; D008940:Mitotic Index; D018087:Plastids / Q000187:drug effects / Q000502:physiology*; D011523:Protoplasts / Q000166:cytology; D032503:Selaginellaceae / Q000166:cytology / Q000187:drug effects / Q000254:growth & development*
chemical_list: D000900:Anti-Bacterial Agents; D000667:Ampicillin