Keiichi Kojima

2.2k total citations
67 papers, 869 citations indexed

About

Keiichi Kojima is a scholar working on Cellular and Molecular Neuroscience, Molecular Biology and Cognitive Neuroscience. According to data from OpenAlex, Keiichi Kojima has authored 67 papers receiving a total of 869 indexed citations (citations by other indexed papers that have themselves been cited), including 49 papers in Cellular and Molecular Neuroscience, 35 papers in Molecular Biology and 8 papers in Cognitive Neuroscience. Recurrent topics in Keiichi Kojima's work include Photoreceptor and optogenetics research (48 papers), Neuroscience and Neuropharmacology Research (24 papers) and Retinal Development and Disorders (11 papers). Keiichi Kojima is often cited by papers focused on Photoreceptor and optogenetics research (48 papers), Neuroscience and Neuropharmacology Research (24 papers) and Retinal Development and Disorders (11 papers). Keiichi Kojima collaborates with scholars based in Japan, United States and Czechia. Keiichi Kojima's co-authors include Yuki Sudo, T. AOYAMA, Seiji Sekine, Yoshinori Shichida, Hiroyuki Takeuchi, Takahiro Yamashita, Yasushi Imamoto, Atsushi Shibukawa, Susumu Yoshizawa and Akimori Wada and has published in prestigious journals such as Proceedings of the National Academy of Sciences, Journal of the American Chemical Society and Journal of Biological Chemistry.

In The Last Decade

Keiichi Kojima

57 papers receiving 851 citations

Peers — A (Enhanced Table)

Peers by citation overlap · career bar shows stage (early→late) cites · hero ref

Name h Career Trend Papers Cites
Keiichi Kojima Japan 18 463 423 106 89 87 67 869
Franz-Josef Braun Germany 11 407 0.9× 720 1.7× 206 1.9× 94 1.1× 41 0.5× 12 1.2k
Liping Nie China 20 230 0.5× 1.0k 2.4× 95 0.9× 46 0.5× 76 0.9× 45 1.4k
Xiandi Gong Canada 22 178 0.4× 677 1.6× 35 0.3× 66 0.7× 34 0.4× 23 1.2k
Soniya Dhanjal Sweden 12 244 0.5× 324 0.8× 78 0.7× 222 2.5× 60 0.7× 21 771
Raphaël Courjaret Qatar 19 281 0.6× 527 1.2× 54 0.5× 26 0.3× 25 0.3× 38 1.0k
Else Marie Fykse Norway 19 627 1.4× 783 1.9× 38 0.4× 19 0.2× 28 0.3× 26 1.3k
Suresh P. Annangudi United States 15 239 0.5× 366 0.9× 35 0.3× 21 0.2× 24 0.3× 21 806
Francisco Barros Spain 26 718 1.6× 1.4k 3.3× 106 1.0× 54 0.6× 12 0.1× 56 1.7k
Peter Illéš Czechia 18 342 0.7× 626 1.5× 210 2.0× 18 0.2× 22 0.3× 47 1.1k

Countries citing papers authored by Keiichi Kojima

Since Specialization
Citations

This map shows the geographic impact of Keiichi Kojima's research. It shows the number of citations coming from papers published by authors working in each country. You can also color the map by specialization and compare the number of citations received by Keiichi Kojima with the expected number of citations based on a country's size and research output (numbers larger than one mean the country cites Keiichi Kojima more than expected).

Fields of papers citing papers by Keiichi Kojima

Since Specialization
Physical SciencesHealth SciencesLife SciencesSocial Sciences

This network shows the impact of papers produced by Keiichi Kojima. Nodes represent research fields, and links connect fields that are likely to share authors. Colored nodes show fields that tend to cite the papers produced by Keiichi Kojima. The network helps show where Keiichi Kojima may publish in the future.

Co-authorship network of co-authors of Keiichi Kojima

This figure shows the co-authorship network connecting the top 25 collaborators of Keiichi Kojima. A scholar is included among the top collaborators of Keiichi Kojima based on the total number of citations received by their joint publications. Widths of edges represent the number of papers authors have co-authored together. Node borders signify the number of papers an author published with Keiichi Kojima. Keiichi Kojima is excluded from the visualization to improve readability, since they are connected to all nodes in the network.

All Works

20 of 20 papers shown
1.
Noji, Tomoyasu, et al.. (2025). Roles of basic amino acid residues in substrate binding and transport of the light-driven anion pump Synechocystis halorhodopsin (SyHR). Journal of Biological Chemistry. 301(4). 108334–108334.
2.
Kojima, Keiichi. (2024). Molecular Diversity of Photosensitive Protein Opsins and Their High Potential for Optogenetic Applications. Biological and Pharmaceutical Bulletin. 47(10). 1600–1609.
3.
Kojima, Keiichi, Masataka Yanagawa, Yasushi Imamoto, et al.. (2024). Convergent mechanism underlying the acquisition of vertebrate scotopic vision. Journal of Biological Chemistry. 300(4). 107175–107175. 1 indexed citations
4.
Hasegawa, Masumi, Toshiaki Hosaka, Keiichi Kojima, et al.. (2024). Cyanorhodopsin-II represents a yellow-absorbing proton-pumping rhodopsin clade within cyanobacteria. The ISME Journal. 18(1). 3 indexed citations
5.
Kojima, Keiichi & Yuki Sudo. (2023). Convergent evolution of animal and microbial rhodopsins. RSC Advances. 13(8). 5367–5381. 19 indexed citations
6.
7.
Kojima, Keiichi, et al.. (2023). Development of light-induced disruptive liposomes (LiDL) as a photoswitchable carrier for intracellular substance delivery. Chemical Communications. 59(49). 7591–7594. 1 indexed citations
8.
Imamoto, Yasushi, et al.. (2023). Role of Monomer/Tetramer Equilibrium of Rod Visual Arrestin in the Interaction with Phosphorylated Rhodopsin. International Journal of Molecular Sciences. 24(5). 4963–4963. 1 indexed citations
9.
10.
Kojima, Keiichi, et al.. (2023). Demonstration of iodide-dependent UVA-triggered growth inhibition in Saccharomyces cerevisiae cells and identification of its suppressive molecules. Biochemical and Biophysical Research Communications. 677. 1–5.
11.
Thiel, Vera, Keiichi Kojima, David M. Ward, et al.. (2023). Identification of a Functionally Efficient and Thermally Stable Outward Sodium-Pumping Rhodopsin (<i>Be</i>NaR) from a Thermophilic Bacterium. Chemical and Pharmaceutical Bulletin. 71(2). 154–164. 3 indexed citations
12.
Shimamura, Tatsuro, Masahiro Hayashi, Norimichi Nomura, et al.. (2023). Structure and mechanism of oxalate transporter OxlT in an oxalate-degrading bacterium in the gut microbiota. Nature Communications. 14(1). 1730–1730. 8 indexed citations
13.
Yasuda, Satoshi, Keiichi Kojima, Tomohiko Hayashi, et al.. (2022). Development of an Outward Proton Pumping Rhodopsin with a New Record in Thermostability by Means of Amino Acid Mutations. The Journal of Physical Chemistry B. 126(5). 1004–1015. 6 indexed citations
14.
Hayashi, Tomohiko, Satoshi Yasuda, K. Suzuki, et al.. (2020). How Does a Microbial Rhodopsin RxR Realize Its Exceptionally High Thermostability with the Proton-Pumping Function Being Retained?. The Journal of Physical Chemistry B. 124(6). 990–1000. 17 indexed citations
15.
Yasuda, Satoshi, Tomohiko Hayashi, Keiichi Kojima, et al.. (2020). Methodology for Further Thermostabilization of an Intrinsically Thermostable Membrane Protein Using Amino Acid Mutations with Its Original Function Being Retained. Journal of Chemical Information and Modeling. 60(3). 1709–1716. 6 indexed citations
16.
Hasegawa, Masumi, Toshiaki Hosaka, Keiichi Kojima, et al.. (2020). A unique clade of light-driven proton-pumping rhodopsins evolved in the cyanobacterial lineage. Scientific Reports. 10(1). 16752–16752. 16 indexed citations
17.
Kojima, Keiichi, et al.. (2020). Applicability of Styrene-Maleic Acid Copolymer for Two Microbial Rhodopsins, RxR and HsSRI. Biophysical Journal. 119(9). 1760–1770. 9 indexed citations
18.
Kojima, Keiichi, et al.. (2020). Lokiarchaeota archaeon schizorhodopsin-2 (LaSzR2) is an inward proton pump displaying a characteristic feature of acid-induced spectral blue-shift. Scientific Reports. 10(1). 20857–20857. 13 indexed citations
19.
Kojima, Keiichi & Michio Kasai. (2008). Effects of Dietary Medium-Chain Triacylglycerol on mRNA Level of Gluconeogenic Enzymes in Malnourished Rats. Journal of Nutritional Science and Vitaminology. 54(6). 507–510. 5 indexed citations
20.
Takeuchi, Hiroyuki, et al.. (2008). Effect of Dietary n-6/n-3 Ratio on Liver n-6/n-3 Ratio and Peroxisomal .BETA.-Oxidation Activity in Rats. Journal of Oleo Science. 57(12). 649–657. 7 indexed citations

Rankless uses publication and citation data sourced from OpenAlex, an open and comprehensive bibliographic database. While OpenAlex provides broad and valuable coverage of the global research landscape, it—like all bibliographic datasets—has inherent limitations. These include incomplete records, variations in author disambiguation, differences in journal indexing, and delays in data updates. As a result, some metrics and network relationships displayed in Rankless may not fully capture the entirety of a scholar's output or impact.

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