Search results for: Ryo Nagao

Items from 1 to 20 out of 29 results

article

Molecular phylogeny of fucoxanthin‐chlorophyll a/c proteins from Chaetoceros gracilis and Lhcq/Lhcf diversity

Minoru Kumazawa, Hiroyo Nishide, Ryo Nagao, Natsuko Inoue‐Kashino, more

Physiologia Plantarum > 174 > 1 > n/a - n/a

Diatoms adapt to various aquatic light environments and play major roles in the global carbon cycle using their unique light‐harvesting system, i.e. fucoxanthin chlorophyll a/c binding proteins (FCPs). Structural analyses of photosystem II (PSII)–FCPII and photosystem I (PSI)–FCPI complexes from the diatom Chaetoceros gracilis have revealed the localization and interactions of many FCPs; however,...

article

Effects of excess light energy on excitation-energy dynamics in a pennate diatom Phaeodactylum tricornutum

Ryo Nagao, Yoshifumi Ueno, Makio Yokono, Jian-Ren Shen, more

Photosynthesis Research > 2019 > 141 > 3 > 355-365

Controlling excitation energy flow is a fundamental ability of photosynthetic organisms to keep a better performance of photosynthesis. Among the organisms, diatoms have unique light-harvesting complexes, fucoxanthin chlorophyll (Chl) a/c-binding proteins. We have recently investigated light-adaptation mechanisms of a marine centric diatom, Chaetoceros gracilis, by spectroscopic techniques. However,...

article

Biochemical characterization of photosystem I complexes having different subunit compositions of fucoxanthin chlorophyll a/c-binding proteins in the diatom Chaetoceros gracilis

Ryo Nagao, Yoshifumi Ueno, Fusamichi Akita, Takehiro Suzuki, more

Photosynthesis Research > 2019 > 140 > 2 > 141-149

Diatoms are dominant phytoplankton in aquatic environments and have unique light-harvesting apparatus, fucoxanthin chlorophyll a/c-binding protein (FCP). Diatom photosystem I (PSI) interacts with specific FCPs (FCPI); however, it remains unclear how PSI cores receive excitation energy from FCPI. To analyze the energy transfer dynamics, it is necessary to isolate both PSI cores and PSI–FCPI complexes...

article

Evaluation of photosynthetic activities in thylakoid membranes by means of Fourier transform infrared spectroscopy

Ryo Nagao, Sho Kitazaki, Takumi Noguchi

Biochimica et Biophysica Acta (BBA) - Bioenergetics > 2018 > 1859 > 2 > 129-136

Light-induced Fourier transformed infrared (FTIR) difference spectroscopy is a powerful method to study the structures and reactions of redox cofactors involved in the photosynthetic electron transport chain. So far, most of the FTIR studies of the reactions of oxygenic photosynthesis have been performed using isolated photosystem I (PSI) and photosystem II (PSII) preparations, which, however, could...

article

Functional role of Lys residues of Psb31 in electrostatic interactions with diatom photosystem II

Ryo Nagao, Takehiro Suzuki, Naoshi Dohmae, Jian‐Ren Shen, more

FEBS Letters > 591 > 20 > 3259 - 3264

We recently revealed that positively charged amino acids of Psb31, an extrinsic subunit found in diatom photosystem II (PSII), are involved in electrostatic interactions with PSII intrinsic subunits. However, the molecular interactions of Psb31 with PSII remain unclear. Here, we report the functional contribution of Lys residues in the binding of Psb31 to PSII using site‐directed mutants of Psb31...

article

Electrostatic interaction of positive charges on the surface of Psb31 with photosystem II in the diatom Chaetoceros gracilis

Ryo Nagao, Takehiro Suzuki, Akinori Okumura, Tomohiro Kihira, more

Biochimica et Biophysica Acta (BBA) - Bioenergetics > 2017 > 1858 > 9 > 779-785

Psb31, a novel extrinsic protein found in diatom photosystem II (PSII), directly binds to PSII core subunits, independent of the other extrinsic proteins, and functions to maintain optimum oxygen evolution. However, how Psb31 electrostatically interacts with PSII intrinsic proteins remains to be clarified. In this study, we examined electrostatic interaction of Psb31 with PSII complexes isolated from...

article

Atomic structure of “multilayer silicene” grown on Ag(111): Dynamical low energy electron diffraction analysis

Kazuaki Kawahara, Tetsuroh Shirasawa, Chun-Liang Lin, Ryo Nagao, more

Surface Science > 2016 > 651 > C > 70-75

We have investigated the atomic structure of the “multilayer silicene” grown on the Ag(111) single crystal surface by using low energy electron diffraction (LEED) and scanning tunneling microscopy (STM). We measured the intensity of the LEED spot as a function of the incident electron energy (I–V curve) and analyzed the I–V curve using a dynamical LEED theory. We have found that the Si(111)(3×3)-Ag...

article

Conversion of photosystem II dimer to monomers during photoinhibition is tightly coupled with decrease in oxygen-evolving activity in the diatom Chaetoceros gracilis

Ryo Nagao, Tatsuya Tomo, Rei Narikawa, Isao Enami, more

Photosynthesis Research > 2016 > 130 > 1-3 > 83-91

The rapid turnover of photosystem II (PSII) in diatoms is thought to be at an exceptionally high rate compared with other oxyphototrophs; however, its molecular mechanisms are largely unknown. In this study, we examined the photodamage and repair processes of PSII in the marine centric diatom Chaetoceros gracilis incubated at 30 or 300 μmol photons m⁻² s⁻¹ in the presence of a de novo protein-synthesis...

chapter

New moving control of mobile robot without collision with wall and obstacles by passive RFID system

Sho Tatsukawa, Tadashi Nakanishi, Ryo Nagao, Tomotaka Wada, more

2015 International Conference on Indoor Positioning and Indoor Navigation (IPIN) > 1 - 7

2015 International Conference on Indoor Positioning and Indoor Navigation (IPIN)

Recently, lack of nurses and care nurses is a serious problem because of the increasing demands of nursing care for age people. So, indoor robot navigation system is important as one of the possible robot technologies to compensate for the lack of nurses. In particular, an indoor robot navigation system using the RFID system which is easy configuration and cheap relatively is studied all over the...

article

Regulation of excitation energy transfer in diatom PSII dimer: How does it change the destination of excitation energy?

Makio Yokono, Ryo Nagao, Tatsuya Tomo, Seiji Akimoto

Biochimica et Biophysica Acta (BBA) - Bioenergetics > 2015 > 1847 > 10 > 1274-1282

Energy transfer dynamics in dimeric photosystem II (PSII) complexes isolated from four diatoms, Chaetoceros gracilis, Cyclotella meneghiniana, Thalassiosira pseudonana, and Phaeodactylum tricornutum, are examined. Time-resolved fluorescence measurements were conducted in the range of 0–80ns. Delayed fluorescence spectra showed a clear difference between PSII monomer and PSII dimer isolated from the...

article

Optimal wavelengths for near-infrared multispectral imaging of atherosclerotic plaque

Ryo Nagao, Katsunori Ishii, Kunio Awazu

Optical Review > 2015 > 22 > 2 > 329-334

Near-infrared multispectral imaging (NIR-MSI) is a potentially effective technique for evaluation of atherosclerotic plaque. In the present study, the optimal wavelength combinations in the NIR wavelength range for detecting plaque were investigated. Atherosclerotic phantoms were observed using a NIR camera at different wavelengths in the range 1150–1790 nm. It was found that the plaque phantom could...

chapter

Moving correction method of a mobile robot using passive RFID system based on obstacle prediction

Tadashi Nakanishi, Manato Fujimoto, Ryo Nagao, Syo Tatsukawa, more

2014 International Conference on Indoor Positioning and Indoor Navigation (IPIN) > 246 - 254

2014 International Conference on Indoor Positioning and Indoor Navigation (IPIN)

Recently, indoor mobile robot navigation systems have been developed all over the world as the technology for assisting aged and physically handicapped people. Especially, the systems using passive RFID with features of low cost and simple composition have attracted attention over the years. However, in these systems, there are two serious problems. 1) A mobile robot performs the meandering moving...

article

Excitation relaxation dynamics and energy transfer in fucoxanthin–chlorophyll a/c-protein complexes, probed by time-resolved fluorescence

Seiji Akimoto, Ayaka Teshigahara, Makio Yokono, Mamoru Mimuro, more

Biochimica et Biophysica Acta (BBA) - Bioenergetics > 2014 > 1837 > 9 > 1514-1521

In algae, light-harvesting complexes contain specific chlorophylls (Chls) and keto-carotenoids; Chl a, Chl c, and fucoxanthin (Fx) in diatoms and brown algae; Chl a, Chl c, and peridinin in photosynthetic dinoflagellates; and Chl a, Chl b, and siphonaxanthin in green algae. The Fx–Chl a/c-protein (FCP) complex from the diatom Chaetoceros gracilis contains Chl c₁, Chl c₂, and the keto-carotenoid, Fx,...

article

Identification of the basic amino acid residues on the PsbP protein involved in the electrostatic interaction with photosystem II

Taishi Nishimura, Chihiro Uno, Kunio Ido, Ryo Nagao, more

Biochimica et Biophysica Acta (BBA) - Bioenergetics > 2014 > 1837 > 9 > 1447-1453

The PsbP protein is an extrinsic subunit of photosystem II (PSII) that is essential for photoautotrophic growth in higher plants. Several crystal structures of PsbP have been reported, but the binding topology of PsbP in PSII has not yet been clarified. In this study, we report that the basic pocket of PsbP, which consists of conserved Arg48, Lys143, and Lys160, is important for the electrostatic...

chapter

A Method for Finding Diffraction Points on Two Edges with Arbitrary Angle and Its Diffracted Fields

Motohiko Iwaida, Jiro Iwashige, Saki Kameyama, Ryo Nagao

2013 Seventh International Conference on Complex, Intelligent, and Software Intensive Systems > 207 - 212

2013 7th International Conference on Complex, Intelligent, and Software Intensive Systems (CISIS)

Estimation of the scattering of electromagnetic waves by buildings and other obstacles is very important for wireless communications in urban area. In our previous work, we have examined the diffracted fields by two horizontal edges with an arbitrary angle. In this paper, we consider the diffracted fields by two edges with an arbitrary angle which change in both horizontal and vertical directions...

article

Light-independent biosynthesis and assembly of the photosystem II complex in the diatom Chaetoceros gracilis

Ryo Nagao, Tatsuya Tomo, Rei Narikawa, Isao Enami, more

FEBS Letters > 2013 > 587 > 9 > 1340-1345

Diatoms can survive for long periods in the dark. However, how biosynthesis of photosynthetic proteins contributes to survival in the dark is poorly understood. Using a radiolabeling technique, we examined whether de novo biosynthesis and assembly of photosynthetic proteins differs in light-adapted vs. dark-adapted marine diatoms (Chaetoceros gracilis). In light-adapted cells, D1 protein was heavily...

article

Comparison of oligomeric states and polypeptide compositions of fucoxanthin chlorophyll a/c-binding protein complexes among various diatom species

Ryo Nagao, Shuji Takahashi, Takehiro Suzuki, Naoshi Dohmae, more

Photosynthesis Research > 2013 > 117 > 1-3 > 281-288

Fucoxanthin chlorophyll a/c-binding protein (FCP) is a unique light-harvesting apparatus in diatoms. Several biochemical characteristics of FCP oligomer and trimer from different diatom species have been reported previously. However, the integration of information about molecular organizations and polypeptides of FCP through a comparison among diatoms has not been published. In this study, we used...

article

Proteases are associated with a minor fucoxanthin chlorophyll a/c-binding protein from the diatom, Chaetoceros gracilis

Ryo Nagao, Tatsuya Tomo, Eri Noguchi, Takehiro Suzuki, more

BBA - Bioenergetics > 2012 > 1817 > 12 > 2110-2117

We previously showed that most subunits in the oxygen-evolving photosystem II (PSII) preparation from the diatom Chaetoceros gracilis are proteolytically unstable. Here, we focused on identifying the proteases that cleave PSII subunits in thylakoid membranes. Major PSII subunits and fucoxanthin chlorophyll (Chl) a/c‐binding proteins (FCPs) were specifically degraded in thylakoid membranes. The PSI...

article

Luminescence of singlet oxygen in photosystem II complexes isolated from cyanobacterium Synechocystis sp. PCC6803 containing monovinyl or divinyl chlorophyll a

Tatsuya Tomo, Hayato Kusakabe, Ryo Nagao, Hisashi Ito, more

BBA - Bioenergetics > 2012 > 1817 > 8 > 1299-1305

The luminescence spectrum of singlet oxygen produced upon excitation at 674nm in the photochemically active photosystem II (PS II) complexes isolated from cyanobacterium Synechocystis sp. PCC 6803 containing different types of chlorophyll, i.e., monovinyl (wild-type) or divinyl (genetically modified) chlorophyll a. The yield of singlet oxygen, estimated using methylene blue as the standard, from the...

chapter

Diffracted Fields on a Building Rooftop Considering Reflection by Ground and Building Rooftop

Jiro Iwashige, Leonard Barolli, Katsuki Hayashi, Ryo Nagao, more

2012 Sixth International Conference on Complex, Intelligent, and Software Intensive Systems > 648 - 653

2012 Sixth International Conference on Complex, Intelligent, and Software Intensive Systems (CISIS)

In order to have an effective utilization of the radio wave resources, it is important to estimate propagation path in the urban area. In our previous work, we have examined the diffracted fields by two edges with an arbitrary angle. In this paper, the characteristics of the diffracted fieldsby two horizontal edges of a building rooftop are discussed for two cases: a building without or with parapets...

Publication date

Set your own date range

INFONA - science communication portal

Search results for: Ryo Nagao

Molecular phylogeny of fucoxanthin‐chlorophyll a/c proteins from Chaetoceros gracilis and Lhcq/Lhcf diversity

Effects of excess light energy on excitation-energy dynamics in a pennate diatom Phaeodactylum tricornutum

Biochemical characterization of photosystem I complexes having different subunit compositions of fucoxanthin chlorophyll a/c-binding proteins in the diatom Chaetoceros gracilis

Evaluation of photosynthetic activities in thylakoid membranes by means of Fourier transform infrared spectroscopy

Functional role of Lys residues of Psb31 in electrostatic interactions with diatom photosystem II

Electrostatic interaction of positive charges on the surface of Psb31 with photosystem II in the diatom Chaetoceros gracilis

Atomic structure of “multilayer silicene” grown on Ag(111): Dynamical low energy electron diffraction analysis

Conversion of photosystem II dimer to monomers during photoinhibition is tightly coupled with decrease in oxygen-evolving activity in the diatom Chaetoceros gracilis

New moving control of mobile robot without collision with wall and obstacles by passive RFID system

Regulation of excitation energy transfer in diatom PSII dimer: How does it change the destination of excitation energy?

Optimal wavelengths for near-infrared multispectral imaging of atherosclerotic plaque

Moving correction method of a mobile robot using passive RFID system based on obstacle prediction

Excitation relaxation dynamics and energy transfer in fucoxanthin–chlorophyll a/c-protein complexes, probed by time-resolved fluorescence

Identification of the basic amino acid residues on the PsbP protein involved in the electrostatic interaction with photosystem II

A Method for Finding Diffraction Points on Two Edges with Arbitrary Angle and Its Diffracted Fields

Light-independent biosynthesis and assembly of the photosystem II complex in the diatom Chaetoceros gracilis

Comparison of oligomeric states and polypeptide compositions of fucoxanthin chlorophyll a/c-binding protein complexes among various diatom species

Proteases are associated with a minor fucoxanthin chlorophyll a/c-binding protein from the diatom, Chaetoceros gracilis

Luminescence of singlet oxygen in photosystem II complexes isolated from cyanobacterium Synechocystis sp. PCC6803 containing monovinyl or divinyl chlorophyll a

Diffracted Fields on a Building Rooftop Considering Reflection by Ground and Building Rooftop

Filter options

Publication date

Publication type

Keywords

Data set

Journal

INFONA - science communication portal

Search results for: Ryo Nagao

Add recipient

Sending message cancelled

Are you sure you want to cancel sending this message?

Send message

Filter options

Publication date

Date range setting

Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.

Publication type

Keywords

Data set

Journal

Reporting an error / abuse

Sending the report failed

Accessibility options