- 著者
- Shuhei Ota Shigeshi Fuchida Haruyo Yamaguchi Takahiro Yamagishi Hiroshi Yamamoto Hiroshi Koshikawa Masanobu Kawachi
- 出版者
- Japan Mendel Society, International Society of Cytology
- 雑誌
- CYTOLOGIA (ISSN:00114545)
- 巻号頁・発行日
- vol.87, no.2, pp.177-187, 2022-06-25 (Released:2022-06-25)
- 参考文献数
- 41
- 被引用文献数
- 2
Seafloor resource development in the future is expected to be accompanied by the mining of metal ores, as these sulfide ores contain valuable metals. However, the mining process is detrimental to marine oceanic environments. As a precautionary approach, innovations in the collection of environmental baseline data and new onboard assessment methods for marine environmental impacts are required. Due to the low cell density in open ocean water, techniques for rapid impact assessment of seawater without sample concentration are required. The purpose of this study was to establish a heavy metal impact assessment system for seawater samples of marine microbes using a portable flow cytometer, On-chip Sort. We established a protocol for detecting heavy metal-induced damage to cells via propidium iodide (PI) staining using algal culture strains (Bathycoccus prasinos NIES-2670, Synechococcus sp. NIES-969, Prochlorococcus sp. NIES-2885, and Cyanobium sp. NIES-981) obtained from the marine environment maintained at the Microbial Culture Collection of the National Institute for Environmental Studies, Tsukuba, Japan. Results showed that PI staining could detect the effects of heavy metals on cells. The proportion of PI-positive cells increased with an increase in the concentration of heavy metal mixture or copper exposure. Compared to cyanobacteria, damaged cells of eukaryotic algae were detected. Therefore, the effects of heavy metals on both eukaryotic and prokaryotic algae can be rapidly assessed via PI-based flow cytometry using samples containing low cell densities.
- 著者
- Shuhei Ota Kenshiro Oshima Tomokazu Yamazaki Tsuyoshi Takeshita Kateřina Bišová Vilém Zachleder Masahira Hattori Shigeyuki Kawano
- 出版者
- Japan Mendel Society, International Society of Cytology
- 雑誌
- CYTOLOGIA (ISSN:00114545)
- 巻号頁・発行日
- vol.84, no.4, pp.323-330, 2019-12-25 (Released:2019-12-20)
- 参考文献数
- 45
- 被引用文献数
- 5
The genus Chlorella is a well-known member of the green algal class Trebouxiophyceae, which is characterized by an immotile and asexual life cycle. Here, we performed an analysis of the whole genome and transcriptome of Parachlorella kessleri NIES-2152 with emphasis on the evolution of meiosis and the flagellar proteins. The Parachlorella transcriptomic data showed that the MID-related RWP-RK genes and meiosis-specific and flagellar proteins were expressed; at the transcriptional level, the DNA repair protein RAD50 was upregulated in the stationary phase, with four-fold more reads per kilobase of transcript per million mapped reads (RPKM) compared with the early stage of culture. In contrast, radial spoke protein genes were down-regulated in the stationary phase. These results suggest that genes for meiotic and flagellar proteins are culture stage-dependent and retain their functions. We presume that the algae lost some of the genes for meiosis and the flagella during asexual evolution, but other genes still possess biological functions other than those related to the flagellum and meiosis.