@article{10.3389/fpls.2025.1569038,
title = {Evolutionary conservation of acylplastoquinone species from cyanobacteria to eukaryotic photosynthetic organisms of green and red lineages},
author = {Ryo Ito and Mizuki Endo and Motohide Aoki and Shoko Fujiwara and Norihiro Sato},
url = {https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2025.1569038},
doi = {10.3389/fpls.2025.1569038},
issn = {1664-462X},
year = {2025},
date = {2025-01-01},
journal = {Frontiers in Plant Science},
volume = {Volume 16 - 2025},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
@article{pmid37317151,
title = {Plastoquinone Lipids: Their Synthesis via a Bifunctional Gene and Physiological Function in a Euryhaline Cyanobacterium, Plastoquinone Lipids: Their Synthesis via a Bifunctional Gene and Physiological Function in a Euryhaline Cyanobacterium, \textit{Synechococcus} sp. PCC 7002},
author = {Mimari Kondo and Motohide Aoki and Kazuho Hirai and Ryo Ito and Mikio Tsuzuki and Norihiro Sato},
doi = {10.3390/microorganisms11051177},
issn = {2076-2607},
year = {2023},
date = {2023-04-01},
urldate = {2023-04-01},
journal = {Microorganisms},
volume = {11},
number = {5},
abstract = {Eukaryotic photosynthetic organisms synthesize triacylglycerols, which are crucial physiologically as major carbon and energy storage compounds and commercially as food oils and raw materials for carbon-neutral biofuel production. TLC analysis has revealed triacylglycerols are present in several cyanobacteria. However, mass spectrometric analysis has shown that freshwater cyanobacterium, sp. PCC 6803, contains plastoquinone-B and acyl plastoquinol with triacylglycerol-like TLC mobility, concomitantly with the absence of triacylglycerol. contains , which is responsible for the bifunctional synthesis of plastoquinone-B and acyl plastoquinol and also for NaCl-stress acclimatizing cell growth. However, information is limited on the taxonomical distribution of these plastoquinone lipids, and their synthesis genes and physiological roles in cyanobacteria. In this study, a euryhaline cyanobacterium, sp. PCC 7002, shows the same plastoquinone lipids as those in , although the levels are much lower than in , triacylglycerol being absent. Furthermore, through an analysis of a disruptant to the homolog of in , it is found that the homolog in , similar to in , contributes bifunctionally to the synthesis of plastoquinone-B and acyl plastoquinol; however, the extent of the contribution of the homolog gene to NaCl acclimatization is smaller than that of in . These observations suggest strain- or ecoregion-dependent development of the physiological roles of plastoquinone lipids in cyanobacteria and show the necessity to re-evaluate previously identified cyanobacterial triacylglycerol through TLC analysis with mass spectrometric techniques.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Eukaryotic photosynthetic organisms synthesize triacylglycerols, which are crucial physiologically as major carbon and energy storage compounds and commercially as food oils and raw materials for carbon-neutral biofuel production. TLC analysis has revealed triacylglycerols are present in several cyanobacteria. However, mass spectrometric analysis has shown that freshwater cyanobacterium, sp. PCC 6803, contains plastoquinone-B and acyl plastoquinol with triacylglycerol-like TLC mobility, concomitantly with the absence of triacylglycerol. contains , which is responsible for the bifunctional synthesis of plastoquinone-B and acyl plastoquinol and also for NaCl-stress acclimatizing cell growth. However, information is limited on the taxonomical distribution of these plastoquinone lipids, and their synthesis genes and physiological roles in cyanobacteria. In this study, a euryhaline cyanobacterium, sp. PCC 7002, shows the same plastoquinone lipids as those in , although the levels are much lower than in , triacylglycerol being absent. Furthermore, through an analysis of a disruptant to the homolog of in , it is found that the homolog in , similar to in , contributes bifunctionally to the synthesis of plastoquinone-B and acyl plastoquinol; however, the extent of the contribution of the homolog gene to NaCl acclimatization is smaller than that of in . These observations suggest strain- or ecoregion-dependent development of the physiological roles of plastoquinone lipids in cyanobacteria and show the necessity to re-evaluate previously identified cyanobacterial triacylglycerol through TLC analysis with mass spectrometric techniques.
@article{pmid37180399,
title = {\textit{slr2103}, a homolog of type-2 diacylglycerol acyltransferase genes, for plastoquinone-related neutral lipid synthesis and NaCl-stress acclimatization in a cyanobacterium, \textit{Synechocystis} sp. PCC 6803},
author = {Mimari Kondo and Motohide Aoki and Kazuho Hirai and Taku Sagami and Ryo Ito and Mikio Tsuzuki and Norihiro Sato},
doi = {10.3389/fpls.2023.1181180},
issn = {1664-462X},
year = {2023},
date = {2023-01-01},
urldate = {2023-01-01},
journal = {Front Plant Sci},
volume = {14},
pages = {1181180},
abstract = {A cyanobacterium, sp. PCC 6803, contains a lipid with triacylglycerol-like TLC mobility but its identity and physiological roles remain unknown. Here, on ESI-positive LC-MS analysis, it is shown that the triacylglycerol-like lipid (lipid X) is related to plastoquinone and can be grouped into two subclasses, X and X, the latter of which is esterified by 16:0 and 18:0. This study further shows that a homolog of type-2 diacylglycerol acyltransferase genes, , is essential for lipid X synthesis: lipid X disappears in a -disruptant whereas it appears in an -overexpressing transformant (OE) of PCC 7942 that intrinsically lacks lipid X. The disruption causes cells to accumulate plastoquinone-C at an abnormally high level whereas overexpression in causes the cells to almost completely lose it. It is thus deduced that encodes a novel acyltransferase that esterifies 16:0 or 18:0 with plastoquinone-C for the synthesis of lipid X. Characterization of the -disruptant in shows that contributes to sedimented-cell growth in a static culture, and to bloom-like structure formation and its expansion by promoting cell aggregation and floatation upon imposition of saline stress (0.3-0.6 M NaCl). These observations provide a basis for elucidation of the molecular mechanism of a novel cyanobacterial strategy to acclimatize to saline stress, and one for development of a system of seawater-utilization and economical harvesting of cyanobacterial cells with high-value added compounds, or blooming control of toxic cyanobacteria.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
A cyanobacterium, sp. PCC 6803, contains a lipid with triacylglycerol-like TLC mobility but its identity and physiological roles remain unknown. Here, on ESI-positive LC-MS analysis, it is shown that the triacylglycerol-like lipid (lipid X) is related to plastoquinone and can be grouped into two subclasses, X and X, the latter of which is esterified by 16:0 and 18:0. This study further shows that a homolog of type-2 diacylglycerol acyltransferase genes, , is essential for lipid X synthesis: lipid X disappears in a -disruptant whereas it appears in an -overexpressing transformant (OE) of PCC 7942 that intrinsically lacks lipid X. The disruption causes cells to accumulate plastoquinone-C at an abnormally high level whereas overexpression in causes the cells to almost completely lose it. It is thus deduced that encodes a novel acyltransferase that esterifies 16:0 or 18:0 with plastoquinone-C for the synthesis of lipid X. Characterization of the -disruptant in shows that contributes to sedimented-cell growth in a static culture, and to bloom-like structure formation and its expansion by promoting cell aggregation and floatation upon imposition of saline stress (0.3-0.6 M NaCl). These observations provide a basis for elucidation of the molecular mechanism of a novel cyanobacterial strategy to acclimatize to saline stress, and one for development of a system of seawater-utilization and economical harvesting of cyanobacterial cells with high-value added compounds, or blooming control of toxic cyanobacteria.
@article{Oishi2022,
title = {Diacylglyceryl-\textit{N,N,N}-trimethylhomoserine-dependent lipid remodeling in a green alga, \textit{Chlorella kessleri</I>},
author = {Yutaro Oishi and Rie Otaki and Yukari Iijima and Eri Kumagai and Motohide Aoki and Mikio Tsuzuki and Shoko Fujiwara and Norihiro Sato},
url = {https://doi.org/10.1038/s42003-021-02927-z},
doi = {10.1038/s42003-021-02927-z},
issn = {2399-3642},
year = {2022},
date = {2022-01-01},
urldate = {2022-01-01},
journal = {Communications Biology},
volume = {5},
number = {1},
pages = {19},
abstract = {Membrane lipid remodeling contributes to the environmental acclimation of plants. In the green lineage, a betaine lipid, diacylglyceryl-N,N,N-trimethylhomoserine (DGTS), is included exclusively among green algae and nonflowering plants. Here, we show that the green alga Chlorella kessleri synthesizes DGTS under phosphorus-deficient conditions through the eukaryotic pathway via the ER. Simultaneously, phosphatidylcholine and phosphatidylethanolamine, which are similar to DGTS in their zwitterionic properties, are almost completely degraded to release 18.1% cellular phosphorus, and to provide diacylglycerol moieties for a part of DGTS synthesis. This lipid remodeling system that substitutes DGTS for extrachloroplast phospholipids to lower the P-quota operates through the expression induction of the BTA1 gene. Investigation of this lipid remodeling system is necessary in a wide range of lower green plants for a comprehensive understanding of their phosphorus deficiency acclimation strategies.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Membrane lipid remodeling contributes to the environmental acclimation of plants. In the green lineage, a betaine lipid, diacylglyceryl-N,N,N-trimethylhomoserine (DGTS), is included exclusively among green algae and nonflowering plants. Here, we show that the green alga Chlorella kessleri synthesizes DGTS under phosphorus-deficient conditions through the eukaryotic pathway via the ER. Simultaneously, phosphatidylcholine and phosphatidylethanolamine, which are similar to DGTS in their zwitterionic properties, are almost completely degraded to release 18.1% cellular phosphorus, and to provide diacylglycerol moieties for a part of DGTS synthesis. This lipid remodeling system that substitutes DGTS for extrachloroplast phospholipids to lower the P-quota operates through the expression induction of the BTA1 gene. Investigation of this lipid remodeling system is necessary in a wide range of lower green plants for a comprehensive understanding of their phosphorus deficiency acclimation strategies.
@article{MIYAUCHI2021102394,
title = {Development of an algal cell-attached solid surface culture system for simultaneous wastewater treatment and biomass production},
author = {Hiroki Miyauchi and Kohei Harada and Yoshino Suzuki and Katsuhiko Okada and Motohide Aoki and Tomonari Umemura and Shoko Fujiwara and Mikio Tsuzuki},
url = {https://www.sciencedirect.com/science/article/pii/S2211926421002137},
doi = {https://doi.org/10.1016/j.algal.2021.102394},
issn = {2211-9264},
year = {2021},
date = {2021-07-06},
journal = {Algal Research},
volume = {58},
pages = {102394},
abstract = {Wastewater treatment using microalgae is receiving growing attention. Here, we have developed a portable tubular system containing an algal cell-coated solid surface for phosphorous recovery. P-depleted Chlorella cells attached to a solid surface removed phosphate from the medium about 70 times faster than P-replete cells. When the cell density was 20 g dry cell weight m−2 or less, P-depleted cells on the solid surface absorbed phosphate from the medium at almost the same rate as in liquid, the maximum capacity per solid surface area being about 6 mg P m−2 min−1. P in inorganic wastewater from chemical factories (ethanol factories; about 4 mg L−1) and in pond water (0.06 mg L−1) was mostly removed within 3 h with a simple device composed of a single solid-surfaced sheet (0.002 m−2) and a portable compact tubular device including 12 such sheets (totally 0.5 m−2), respectively. Simultaneously, cellular growth was confirmed with both wastewater and pond water. These findings suggested that the attached cell culture system, in which medium exchange to prepare P-depleted cells is much easier than in liquid cultures, is promising for dual use for biomass production and wastewater treatment.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Wastewater treatment using microalgae is receiving growing attention. Here, we have developed a portable tubular system containing an algal cell-coated solid surface for phosphorous recovery. P-depleted Chlorella cells attached to a solid surface removed phosphate from the medium about 70 times faster than P-replete cells. When the cell density was 20 g dry cell weight m−2 or less, P-depleted cells on the solid surface absorbed phosphate from the medium at almost the same rate as in liquid, the maximum capacity per solid surface area being about 6 mg P m−2 min−1. P in inorganic wastewater from chemical factories (ethanol factories; about 4 mg L−1) and in pond water (0.06 mg L−1) was mostly removed within 3 h with a simple device composed of a single solid-surfaced sheet (0.002 m−2) and a portable compact tubular device including 12 such sheets (totally 0.5 m−2), respectively. Simultaneously, cellular growth was confirmed with both wastewater and pond water. These findings suggested that the attached cell culture system, in which medium exchange to prepare P-depleted cells is much easier than in liquid cultures, is promising for dual use for biomass production and wastewater treatment.
@article{今崎龍之介2020,
title = {超薄層クロマトグラフィー用の水平式ミニチュアTLC展開槽の試作と評価},
author = {今崎,龍之介 and 近藤,啓太 and 谷,夏海 and 青木,元秀 and 熊田,英峰 and 内田,達也 and 長縄,豪 and 嶋田,泰佑 and 田口,嘉彦 and 佐藤,浩明 and 安井,隆雄 and 梅村,知也},
doi = {10.2116/bunsekikagaku.69.553},
year = {2020},
date = {2020-01-01},
journal = {分析化学},
volume = {69},
number = {10.11},
pages = {553-558},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
東京薬科大学生命科学部 助教 同大学院 生命科学研究科 助教 TUPLS Assistant Professor in Life Sciences Co-director of Biochemistry and Molecular biology Research Team, Laboratory of Environmental and Bioanalytical Chemistry
資格 (License)
甲種危険物取扱者 (Class A Hazardous Materials Engineer) 認定電気工事従事者 (Journeyman Electrician Certified by METI Japan) 第二種電気工事士 (Second Class Electrician License) 一級小型船舶操縦士 (First-Class Small Boat Pilot) – 陸から離れた海洋・湖沼などでの水性生物サンプリングができます（外洋まで出れる資格ですが基本”丘”船長です） 第１級海上無線通信士 (Maritime First–Class Radio Operator) – 国際航海に対応 など
職歴 (Previous Appointments)
Assistant Professor in Life Sciences, 2013-, Tokyo University of Pharmacy and Life Sciences Research Associate in Life Sciences, 2005-2013, Tokyo University of Pharmacy and Life Sciences Postdoctoral Researcher, 2004-2005, Biomarker Science Co.,Ltd. Research Assistant, 2002-2004, Tokyo University of Pharmacy and Life Sciences Teaching Assistant, 1999-2002, Tokyo University of Pharmacy and Life Sciences
学歴 (Education)
Ph.D., Life Sciences, Tokyo University of Pharmacy and Life Sciences, Tokyo, Japan (2004) M.Sc., Life Sciences, Tokyo University of Pharmacy and Life Sciences, Tokyo, Japan (2001) B.Sc., Molecular Biology and Biochemistry, Saitama University, Saitama, Japan (1999)
