Publications by authors named "Hisato Ikegaya"
Article Synopsis
- Filamentous manganese oxide particles in suboxic water zones play a crucial role in elemental cycles and are believed to be formed by bacteria, but the environmental factors driving their formation are still unclear.
- This study shows that algal extracellular polysaccharides enhance manganese oxidation by certain bacteria, leading to the production of these filamentous particles.
- Investigating Lake Biwa, researchers found a correlation between the density of manganese particles and phytoplankton, particularly green algae, suggesting that algal mucilage is vital for forming these manganese oxide particles in the lake’s near-bottom layer.
Article Synopsis
- The genus Spirogyra consists of around 380 species found in freshwater across the globe, making species identification challenging due to reliance on sexual characteristics from samples.
- Researchers created a new method to induce sexual reproduction in laboratory-grown Spirogyra filaments, which led to the identification of 13 species from 52 strains collected in Japan.
- Two species were linked to the closely-related but uncertain genus Temnogyra, suggesting that it may not be valid to separate it from Spirogyra based on genetic analysis, similar to findings with another genus, Sirogonium.
We succeeded in inducing conjugation of Spirogyra castanacea by incubating algal filaments on agar plate. Conjugation could be induced using clone culture. The scalariform conjugation was generally observed, while lateral conjugation was rarely.
View Article and Find Full Text PDFSome species of Spirogyra can anchor to substratum with rod- or rosette-shaped rhizoid (hapteron). The rhizoid differentiation can be induced by cutting algal filaments in a laboratory. Requirement of contact stimulation for rhizoid differentiation has been reported (Nagata in Plant Cell Physiol 14:531-541, 1973a).
View Article and Find Full Text PDFSome species of Spirogyra living in streams can anchor to the substratum by differentiating a rhizoid from a terminal cell of a filament. Rhizoid differentiation occurs in the light but not in the dark. When a filament of Spirogyra sp.
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