Akiko Yokoyama
University of Tsukuba
31Publications
10H-index
297Citations
Publications 31
Newest
Published on Feb 26, 2019in The ISME Journal 9.52
Yuichiro Kashiyama3
Estimated H-index: 3
,
Akiko Yokoyama10
Estimated H-index: 10
(University of Tsukuba)
+ 41 AuthorsMasami Nakazawa12
Estimated H-index: 12
(Osaka Prefecture University)
Extant eukaryote ecology is primarily sustained by oxygenic photosynthesis, in which chlorophylls play essential roles. The exceptional photosensitivity of chlorophylls allows them to harvest solar energy for photosynthesis, but on the other hand, they also generate cytotoxic reactive oxygen species. A risk of such phototoxicity of the chlorophyll must become particularly prominent upon dynamic cellular interactions that potentially disrupt the mechanisms that are designed to quench photoexcited...
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Published on Sep 1, 2018in Science of The Total Environment 4.61
Azusa Oita3
Estimated H-index: 3
,
Yuuri Tsuboi9
Estimated H-index: 9
+ 5 AuthorsJ. Kikuchi52
Estimated H-index: 52
(Nagoya University)
Abstract There is an increasing need for assessing aquatic ecosystems that are globally endangered. Since aquatic ecosystems are complex, integrated consideration of multiple factors utilizing omics technologies can help us better understand aquatic ecosystems. An integrated strategy linking three analytical (machine learning, factor mapping, and forecast-error-variance decomposition) approaches for extracting the features of surface water from datasets comprising ions, metabolites, and microorg...
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Published on Jan 1, 2018in Algal Research-Biomass Biofuels and Bioproducts 3.75
Mikihide Demura2
Estimated H-index: 2
(University of Tsukuba),
Masaki Yoshida11
Estimated H-index: 11
(University of Tsukuba)
+ 11 AuthorsMakoto Osaka1
Estimated H-index: 1
Abstract Coastal areas in the Tohoku region were severely damaged by the tsunami that followed the March 2011 earthquake. Consequently, many lands have become non-arable. To assess the use of these non-arable lands for the production of algal biomass, we carried out experimental cultivations of native algal communities in Minamisoma city, Fukushima Prefecture, located in the cool temperate zone of Japan. Productivity of the native algal community was measured using 1-m 2 raceway ponds (120 L) an...
3 Citations Source Cite
Published on Jun 1, 2016in Journal of Phycology 3.00
Shinichi Takaichi34
Estimated H-index: 34
(Nippon Medical School),
Akiko Yokoyama10
Estimated H-index: 10
(University of Tsukuba)
+ 2 AuthorsAkio Murakami23
Estimated H-index: 23
(Kobe University)
Carotenoid composition is very diverse in Rhodophyta. In this study, we investigated whether this variation is related to the phylogeny of this group. Rhodophyta consists of seven classes, and they can be divided into two groups on the basis of their morphology. The unicellular group (Cyanidiophyceae, Porphyridiophyceae, Rhodellophyceae, and Stylonematophyceae) contained only β-carotene and zeaxanthin, "ZEA-type carotenoids." In contrast, within the macrophytic group (Bangiophyceae, Compsopogono...
6 Citations Source Cite
Published on Mar 1, 2015in Journal of Plant Research 2.00
Takeshi Nakayama18
Estimated H-index: 18
(University of Tsukuba),
Atsushi Nakamura17
Estimated H-index: 17
(University of Tsukuba)
+ 3 AuthorsKen-ichiro Ishida24
Estimated H-index: 24
(University of Tsukuba)
This study investigated the taxonomic affiliation of the algal strain nak-9, which has been reported to absorb radioactive cesium with high efficiency, using light and electron microscopy, and molecular phylogenetic analysis based on 18S ribosomal RNA gene (rDNA) sequences. This alga is spherical and coccoid, with a smooth cell wall, large vacuole, crystalline structure, reddish globule, and refractile granules (lamellate vesicles). The cells possess one to several greenish parietal chloroplasts...
10 Citations Source Cite
Published on Jan 1, 2014in Journal of Plant Research 2.00
Shin ya Fukuda1
Estimated H-index: 1
(University of Tsukuba),
Koji Iwamoto11
Estimated H-index: 11
(University of Tsukuba)
+ 5 AuthorsYoshihiro Shiraiwa24
Estimated H-index: 24
(University of Tsukuba)
The Fukushima 1 Nuclear Power Plant accident in March 2011 released an enormously high level of radionuclides into the environment, a total estimation of 6.3 × 1017 Bq represented by mainly radioactive Cs, Sr, and I. Because these radionuclides are biophilic, an urgent risk has arisen due to biological intake and subsequent food web contamination in the ecosystem. Thus, urgent elimination of radionuclides from the environment is necessary to prevent substantial radiopollution of organisms. In th...
30 Citations Source Cite
Published on Dec 1, 2014in Protist 2.70
Takashi Shiratori7
Estimated H-index: 7
(University of Tsukuba),
Akiko Yokoyama10
Estimated H-index: 10
(University of Tsukuba),
Ken-ichiro Ishida24
Estimated H-index: 24
(University of Tsukuba)
Abollifer is a little-known genus of marine heterotrophic flagellates with no ultrastructural and molecular information, and its taxonomic position remains uncertain. In this study, we report a new species of Abollifer , Abollifer globosa sp. nov., isolated from a seawater sample collected at Tokyo Bay. To reveal the taxonomic position and morphological characteristics of A. globosa , we performed light and electron microscopic observations and a phylogenetic analysis using small subunit ribosom...
7 Citations Source Cite
Published on Aug 19, 2013in FEBS Letters 3.00
Yuichiro Kashiyama3
Estimated H-index: 3
(Fukui University of Technology),
Akiko Yokoyama10
Estimated H-index: 10
(University of Tsukuba)
+ 4 AuthorsHitoshi Tamiaki41
Estimated H-index: 41
(Ritsumeikan University)
Both 132,173-cyclopheophorbide a and b enols were produced along with ingestion of green microalgae containing chlorophylls a and b by a centrohelid protist (phycophagy). The results suggest that chlorophyll b as well as chlorophyll a were directly degraded to colored yet non-phototoxic catabolites in the protistan phycophagic process. Such a simple process by the predators makes a contrast to the much sophisticated chlorophyll degradation process of land plants and some algae, where phototoxici...
15 Citations Source Cite
Published on Mar 15, 2012in Algae 1.56
Joe Scott11
Estimated H-index: 11
,
Eun-Chan Yang3
Estimated H-index: 3
+ 8 AuthorsJeong-Kwang Park1
Estimated H-index: 1
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Published on Mar 17, 2012in Acta Biochimica Polonica 1.24
Shinichi Takaichi34
Estimated H-index: 34
,
Akio Murakami23
Estimated H-index: 23
+ 1 AuthorsAkiko Yokoyama10
Estimated H-index: 10
Carotenoids in eukaryotic phototrophic organisms can be classified into two groups; β-carotene and its derivatives, and α-carotene and its derivatives. We reexamined distribution of α-carotene and its derivatives among various taxa of aquatic algae (17 classes) and land plants. α-carotene and its derivatives were found from Rhodophyceae (macrophytic type), Cryptophyceae, Euglenophyceae, Chlorarachniophyceae, Prasinophyceae, Chlorophyceae, Ulvophyceae, Charophyceae, and land plants, while they co...
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