Isolation and characterization of a motility-defective mutant of Euglena gracilis
Euglena gracilis is a green photosynthetic microalga that swims using its flagellum. This species has been used as a model organism for over half a century to study its metabolism and the mechanisms of its behavior. The development of mass-cultivation technology has led to E. gracilis application as...
| Main Authors: | , , , , , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
PeerJ Inc.
2020-09-01
|
| Series: | PeerJ |
| Subjects: | |
| Online Access: | https://peerj.com/articles/10002.pdf |
| _version_ | 1827610990413348864 |
|---|---|
| author | Shuki Muramatsu Kohei Atsuji Koji Yamada Kazunari Ozasa Hideyuki Suzuki Takuto Takeuchi Yuka Hashimoto-Marukawa Yusuke Kazama Tomoko Abe Kengo Suzuki Osamu Iwata |
| author_facet | Shuki Muramatsu Kohei Atsuji Koji Yamada Kazunari Ozasa Hideyuki Suzuki Takuto Takeuchi Yuka Hashimoto-Marukawa Yusuke Kazama Tomoko Abe Kengo Suzuki Osamu Iwata |
| author_sort | Shuki Muramatsu |
| collection | DOAJ |
| description | Euglena gracilis is a green photosynthetic microalga that swims using its flagellum. This species has been used as a model organism for over half a century to study its metabolism and the mechanisms of its behavior. The development of mass-cultivation technology has led to E. gracilis application as a feedstock in various products such as foods. Therefore, breeding of E. gracilis has been attempted to improve the productivity of this feedstock for potential industrial applications. For this purpose, a characteristic that preserves the microalgal energy e.g., reduces motility, should be added to the cultivars. The objective of this study was to verify our hypothesis that E. gracilis locomotion-defective mutants are suitable for industrial applications because they save the energy required for locomotion. To test this hypothesis, we screened for E. gracilis mutants from Fe-ion-irradiated cell suspensions and established a mutant strain, ${\mathrm{M}}_{3}^{-}$ M 3 − ZFeL, which shows defects in flagellum formation and locomotion. The mutant strain exhibits a growth rate comparable to that of the wild type when cultured under autotrophic conditions, but had a slightly slower growth under heterotrophic conditions. It also stores 1.6 times the amount of paramylon, a crystal of β-1,3-glucan, under autotrophic culture conditions, and shows a faster sedimentation compared with that of the wild type, because of the deficiency in mobility and probably the high amount of paramylon accumulation. Such characteristics make E. gracilis mutant cells suitable for cost-effective mass cultivation and harvesting. |
| first_indexed | 2024-03-09T07:58:40Z |
| format | Article |
| id | doaj.art-7e4d5a5cf2f04e5a9e36e0e47a126dd2 |
| institution | Directory Open Access Journal |
| issn | 2167-8359 |
| language | English |
| last_indexed | 2024-03-09T07:58:40Z |
| publishDate | 2020-09-01 |
| publisher | PeerJ Inc. |
| record_format | Article |
| series | PeerJ |
| spelling | doaj.art-7e4d5a5cf2f04e5a9e36e0e47a126dd22023-12-03T00:49:15ZengPeerJ Inc.PeerJ2167-83592020-09-018e1000210.7717/peerj.10002Isolation and characterization of a motility-defective mutant of Euglena gracilisShuki Muramatsu0Kohei Atsuji1Koji Yamada2Kazunari Ozasa3Hideyuki Suzuki4Takuto Takeuchi5Yuka Hashimoto-Marukawa6Yusuke Kazama7Tomoko Abe8Kengo Suzuki9Osamu Iwata10Department of Health Science, Showa Women’s University, Tokyo, Japaneuglena Co., Ltd., Tokyo, Japaneuglena Co., Ltd., Tokyo, JapanBioengineering Laboratory, Cluster for Pioneering Research, RIKEN, Saitama, Japaneuglena Co., Ltd., Tokyo, Japaneuglena Co., Ltd., Tokyo, Japaneuglena Co., Ltd., Tokyo, JapanRIKEN Nishina Center, Saitama, JapanRIKEN Nishina Center, Saitama, Japaneuglena Co., Ltd., Tokyo, Japaneuglena Co., Ltd., Tokyo, JapanEuglena gracilis is a green photosynthetic microalga that swims using its flagellum. This species has been used as a model organism for over half a century to study its metabolism and the mechanisms of its behavior. The development of mass-cultivation technology has led to E. gracilis application as a feedstock in various products such as foods. Therefore, breeding of E. gracilis has been attempted to improve the productivity of this feedstock for potential industrial applications. For this purpose, a characteristic that preserves the microalgal energy e.g., reduces motility, should be added to the cultivars. The objective of this study was to verify our hypothesis that E. gracilis locomotion-defective mutants are suitable for industrial applications because they save the energy required for locomotion. To test this hypothesis, we screened for E. gracilis mutants from Fe-ion-irradiated cell suspensions and established a mutant strain, ${\mathrm{M}}_{3}^{-}$ M 3 − ZFeL, which shows defects in flagellum formation and locomotion. The mutant strain exhibits a growth rate comparable to that of the wild type when cultured under autotrophic conditions, but had a slightly slower growth under heterotrophic conditions. It also stores 1.6 times the amount of paramylon, a crystal of β-1,3-glucan, under autotrophic culture conditions, and shows a faster sedimentation compared with that of the wild type, because of the deficiency in mobility and probably the high amount of paramylon accumulation. Such characteristics make E. gracilis mutant cells suitable for cost-effective mass cultivation and harvesting.https://peerj.com/articles/10002.pdfEuglena gracilisMotility defectHeavy-ion beam irradiationMicroalgaeParamylon |
| spellingShingle | Shuki Muramatsu Kohei Atsuji Koji Yamada Kazunari Ozasa Hideyuki Suzuki Takuto Takeuchi Yuka Hashimoto-Marukawa Yusuke Kazama Tomoko Abe Kengo Suzuki Osamu Iwata Isolation and characterization of a motility-defective mutant of Euglena gracilis PeerJ Euglena gracilis Motility defect Heavy-ion beam irradiation Microalgae Paramylon |
| title | Isolation and characterization of a motility-defective mutant of Euglena gracilis |
| title_full | Isolation and characterization of a motility-defective mutant of Euglena gracilis |
| title_fullStr | Isolation and characterization of a motility-defective mutant of Euglena gracilis |
| title_full_unstemmed | Isolation and characterization of a motility-defective mutant of Euglena gracilis |
| title_short | Isolation and characterization of a motility-defective mutant of Euglena gracilis |
| title_sort | isolation and characterization of a motility defective mutant of euglena gracilis |
| topic | Euglena gracilis Motility defect Heavy-ion beam irradiation Microalgae Paramylon |
| url | https://peerj.com/articles/10002.pdf |
| work_keys_str_mv | AT shukimuramatsu isolationandcharacterizationofamotilitydefectivemutantofeuglenagracilis AT koheiatsuji isolationandcharacterizationofamotilitydefectivemutantofeuglenagracilis AT kojiyamada isolationandcharacterizationofamotilitydefectivemutantofeuglenagracilis AT kazunariozasa isolationandcharacterizationofamotilitydefectivemutantofeuglenagracilis AT hideyukisuzuki isolationandcharacterizationofamotilitydefectivemutantofeuglenagracilis AT takutotakeuchi isolationandcharacterizationofamotilitydefectivemutantofeuglenagracilis AT yukahashimotomarukawa isolationandcharacterizationofamotilitydefectivemutantofeuglenagracilis AT yusukekazama isolationandcharacterizationofamotilitydefectivemutantofeuglenagracilis AT tomokoabe isolationandcharacterizationofamotilitydefectivemutantofeuglenagracilis AT kengosuzuki isolationandcharacterizationofamotilitydefectivemutantofeuglenagracilis AT osamuiwata isolationandcharacterizationofamotilitydefectivemutantofeuglenagracilis |