Mark R. O’Brian

3.7k total citations
81 papers, 3.0k citations indexed

About

Mark R. O’Brian is a scholar working on Plant Science, Molecular Biology and Environmental Engineering. According to data from OpenAlex, Mark R. O’Brian has authored 81 papers receiving a total of 3.0k indexed citations (citations by other indexed papers that have themselves been cited), including 68 papers in Plant Science, 34 papers in Molecular Biology and 16 papers in Environmental Engineering. Recurrent topics in Mark R. O’Brian's work include Legume Nitrogen Fixing Symbiosis (63 papers), Porphyrin Metabolism and Disorders (28 papers) and Plant Micronutrient Interactions and Effects (26 papers). Mark R. O’Brian is often cited by papers focused on Legume Nitrogen Fixing Symbiosis (63 papers), Porphyrin Metabolism and Disorders (28 papers) and Plant Micronutrient Interactions and Effects (26 papers). Mark R. O’Brian collaborates with scholars based in United States, Japan and Uruguay. Mark R. O’Brian's co-authors include Indu Sangwan, Robert J. Maier, Heather R. Panek, Zhenhao Qi, Iqbal Hamza, Sarita Chauhan, Sumant Puri, Jianhua Yang, Richard Hassett and Natalie D. King and has published in prestigious journals such as Science, Proceedings of the National Academy of Sciences and Journal of Biological Chemistry.

In The Last Decade

Mark R. O’Brian

80 papers receiving 2.9k citations

Peers — A (Enhanced Table)

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

Name h Career Trend Papers Cites
Mark R. O’Brian United States 35 1.4k 1.4k 429 400 280 81 3.0k
Hans‐Martin Fischer Switzerland 38 1.3k 0.9× 2.5k 1.8× 406 0.9× 157 0.4× 57 0.2× 84 4.2k
Danièle Touati France 19 1.0k 0.7× 680 0.5× 121 0.3× 83 0.2× 87 0.3× 24 2.5k
B. R. Byers United States 26 752 0.5× 444 0.3× 108 0.3× 89 0.2× 182 0.7× 46 2.0k
Skorn Mongkolsuk Thailand 24 722 0.5× 590 0.4× 122 0.3× 136 0.3× 31 0.1× 82 1.7k
Paiboon Vattanaviboon Thailand 28 1.0k 0.7× 636 0.5× 142 0.3× 72 0.2× 34 0.1× 98 2.2k
Donald A. Cooksey United States 33 633 0.4× 2.0k 1.4× 96 0.2× 336 0.8× 28 0.1× 62 3.3k
Tae-Kwang Oh South Korea 36 2.8k 1.9× 547 0.4× 50 0.1× 143 0.4× 79 0.3× 108 3.7k
J E Arceneaux United States 22 547 0.4× 284 0.2× 76 0.2× 58 0.1× 133 0.5× 34 1.4k
Elaine R. Frawley United States 16 716 0.5× 90 0.1× 121 0.3× 218 0.5× 96 0.3× 20 1.2k
Margaret Wexler United Kingdom 25 838 0.6× 559 0.4× 197 0.5× 30 0.1× 43 0.2× 33 2.0k

Countries citing papers authored by Mark R. O’Brian

Since Specialization
Citations

This map shows the geographic impact of Mark R. O’Brian'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 Mark R. O’Brian with the expected number of citations based on a country's size and research output (numbers larger than one mean the country cites Mark R. O’Brian more than expected).

Fields of papers citing papers by Mark R. O’Brian

Since Specialization
Physical SciencesHealth SciencesLife SciencesSocial Sciences

This network shows the impact of papers produced by Mark R. O’Brian. 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 Mark R. O’Brian. The network helps show where Mark R. O’Brian may publish in the future.

Co-authorship network of co-authors of Mark R. O’Brian

This figure shows the co-authorship network connecting the top 25 collaborators of Mark R. O’Brian. A scholar is included among the top collaborators of Mark R. O’Brian 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 Mark R. O’Brian. Mark R. O’Brian 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.
2.
Matsumoto, Yuki, et al.. (2020). Mechanistic insights into heme-mediated transcriptional regulation via a bacterial manganese-binding iron regulator, iron response regulator (Irr). Journal of Biological Chemistry. 295(32). 11316–11325. 7 indexed citations
3.
Chatterjee, Anushila & Mark R. O’Brian. (2018). Rapid evolution of a bacterial iron acquisition system. Molecular Microbiology. 108(1). 90–100. 19 indexed citations
4.
Rosconi, Federico, Juan M. Lázaro‐Martínez, Graciela Buldain, et al.. (2016). HmuS and HmuQ of Ensifer/Sinorhizobium meliloti degrade heme in vitro and participate in heme metabolism in vivo. BioMetals. 29(2). 333–347. 4 indexed citations
5.
Kitatsuji, Chihiro, Masaki Kurogochi, Takeshi Uchida, et al.. (2016). Protein oxidation mediated by heme-induced active site conversion specific for heme-regulated transcription factor, iron response regulator. Scientific Reports. 6(1). 18703–18703. 23 indexed citations
6.
O’Brian, Mark R., et al.. (2016). The Bradyrhizobium japonicum Ferrous Iron Transporter FeoAB Is Required for Ferric Iron Utilization in Free Living Aerobic Cells and for Symbiosis. Journal of Biological Chemistry. 291(30). 15653–15662. 25 indexed citations
7.
O’Brian, Mark R.. (2015). Perception and Homeostatic Control of Iron in the Rhizobia and Related Bacteria. Annual Review of Microbiology. 69(1). 229–245. 41 indexed citations
8.
O’Brian, Mark R., et al.. (2012). Manganese is required for oxidative metabolism in unstressed Bradyrhizobium japonicum cells. Molecular Microbiology. 84(4). 766–777. 26 indexed citations
9.
O’Brian, Mark R., et al.. (2009). The mntH gene encodes the major Mn2+ transporter in Bradyrhizobium japonicum and is regulated by manganese via the Fur protein. Molecular Microbiology. 72(2). 399–409. 46 indexed citations
10.
Yang, Jianhua, Indu Sangwan, Andrea Lindemann, et al.. (2006). Bradyrhizobium japonicum senses iron through the status of haem to regulate iron homeostasis and metabolism. Molecular Microbiology. 60(2). 427–437. 82 indexed citations
11.
Yang, Jianhua, Heather R. Panek, & Mark R. O’Brian. (2006). Oxidative stress promotes degradation of the Irr protein to regulate haem biosynthesis in Bradyrhizobium japonicum. Molecular Microbiology. 60(1). 209–218. 48 indexed citations
12.
Yang, Jianhua, Koichiro Ishimori, & Mark R. O’Brian. (2004). Two Heme Binding Sites Are Involved in the Regulated Degradation of the Bacterial Iron Response Regulator (Irr) Protein. Journal of Biological Chemistry. 280(9). 7671–7676. 68 indexed citations
13.
O’Brian, Mark R., et al.. (2003). A Novel DNA-binding Site for the Ferric Uptake Regulator (Fur) Protein from Bradyrhizobium japonicum. Journal of Biological Chemistry. 278(40). 38395–38401. 40 indexed citations
14.
O’Brian, Mark R. & Linda Thöny‐Meyer. (2002). Biochemistry, regulation and genomics of haem biosynthesis in prokaryotes. Advances in microbial physiology. 46. 257–318. 47 indexed citations
15.
Qi, Zhenhao & Mark R. O’Brian. (2002). Interaction between the Bacterial Iron Response Regulator and Ferrochelatase Mediates Genetic Control of Heme Biosynthesis. Molecular Cell. 9(1). 155–162. 93 indexed citations
16.
O’Brian, Mark R., et al.. (1995). The Rhizobial hemA Gene Is Required for Symbiosis in Species with Deficient [delta]-Aminolevulinic Acid Uptake Activity. PLANT PHYSIOLOGY. 108(4). 1547–1552. 16 indexed citations
17.
Chauhan, Sarita & Mark R. O’Brian. (1995). A Mutant Bradyrhizobium japonicum δ-Aminolevulinic Acid Dehydratase with an Altered Metal Requirement Functions in Situ for Tetrapyrrole Synthesis in Soybean Root Nodules. Journal of Biological Chemistry. 270(34). 19823–19827. 31 indexed citations
18.
Sangwan, Indu, et al.. (1995). gsa1 Is a Universal Tetrapyrrole Synthesis Gene in Soybean and Is Regulated by a GAGA Element. Journal of Biological Chemistry. 270(13). 7387–7393. 19 indexed citations
19.
Smith, M. W., et al.. (1994). Plant [delta]-Aminolevulinic Acid Dehydratase (Expression in Soybean Root Nodules and Evidence for a Bacterial Lineage of the Alad Gene). PLANT PHYSIOLOGY. 104(4). 1411–1417. 27 indexed citations
20.
O’Brian, Mark R. & Robert J. Maier. (1988). Hydrogen Metabolism in Rhizobium: Energetics, Regulation, Enzymology and Genetics. Advances in microbial physiology. 29. 1–52. 20 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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