John O’Callaghan

2.9k total citations
41 papers, 2.3k citations indexed

About

John O’Callaghan is a scholar working on Molecular Biology, Food Science and Nutrition and Dietetics. According to data from OpenAlex, John O’Callaghan has authored 41 papers receiving a total of 2.3k indexed citations (citations by other indexed papers that have themselves been cited), including 18 papers in Molecular Biology, 14 papers in Food Science and 12 papers in Nutrition and Dietetics. Recurrent topics in John O’Callaghan's work include Probiotics and Fermented Foods (14 papers), Plant Pathogens and Fungal Diseases (8 papers) and Mycotoxins in Agriculture and Food (7 papers). John O’Callaghan is often cited by papers focused on Probiotics and Fermented Foods (14 papers), Plant Pathogens and Fungal Diseases (8 papers) and Mycotoxins in Agriculture and Food (7 papers). John O’Callaghan collaborates with scholars based in Ireland, United Kingdom and Spain. John O’Callaghan's co-authors include Alan D. W. Dobson, Gerald J. Meyer, Donald V. Scaltrito, David W. Thompson, Paul W. O’Toole, R. Paul Ross, Tom Beresford, Mark X. Caddick, Declan M. Soden and Rita M. Hickey and has published in prestigious journals such as PLoS ONE, Applied and Environmental Microbiology and Coordination Chemistry Reviews.

In The Last Decade

John O’Callaghan

40 papers receiving 2.2k citations

Peers — A (Enhanced Table)

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

Name h Career Trend Papers Cites
John O’Callaghan Ireland 27 894 643 583 416 275 41 2.3k
Bart Samyn Belgium 30 1.3k 1.5× 522 0.8× 314 0.5× 194 0.5× 365 1.3× 62 2.4k
Zhiqiang Xiong China 39 1.9k 2.2× 549 0.9× 1.1k 1.9× 501 1.2× 498 1.8× 237 5.1k
Om Prakash United States 31 1.5k 1.6× 754 1.2× 274 0.5× 301 0.7× 268 1.0× 136 3.6k
Weijun Chen China 33 648 0.7× 645 1.0× 1.7k 2.9× 530 1.3× 275 1.0× 94 3.3k
Arthur J.G. Moir United Kingdom 30 2.1k 2.3× 344 0.5× 668 1.1× 351 0.8× 288 1.0× 76 3.7k
Wentao Xu China 34 2.2k 2.5× 1.5k 2.4× 462 0.8× 221 0.5× 216 0.8× 160 4.0k
S.J. Firbank United Kingdom 22 1.4k 1.6× 281 0.4× 333 0.6× 538 1.3× 180 0.7× 32 2.2k
Neil M. Rigby United Kingdom 39 1.0k 1.2× 786 1.2× 1.6k 2.8× 768 1.8× 219 0.8× 106 4.5k
Peter A. Lund United Kingdom 36 2.3k 2.6× 362 0.6× 418 0.7× 219 0.5× 330 1.2× 99 4.0k
Guangqiang Wang China 32 1.2k 1.3× 317 0.5× 1.1k 1.9× 467 1.1× 346 1.3× 146 3.3k

Countries citing papers authored by John O’Callaghan

Since Specialization
Citations

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

Fields of papers citing papers by John O’Callaghan

Since Specialization
Physical SciencesHealth SciencesLife SciencesSocial Sciences

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

Co-authorship network of co-authors of John O’Callaghan

This figure shows the co-authorship network connecting the top 25 collaborators of John O’Callaghan. A scholar is included among the top collaborators of John O’Callaghan 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 John O’Callaghan. John O’Callaghan 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.
Bottacini, Francesca, John O’Callaghan, Eoghan Casey, et al.. (2021). Infant-Associated Bifidobacterial β-Galactosidases and Their Ability to Synthesize Galacto-Oligosaccharides. Frontiers in Microbiology. 12. 662959–662959. 12 indexed citations
2.
O’Callaghan, John, et al.. (2018). Bovine glycomacropeptide promotes the growth of Bifidobacterium longum ssp. infantis and modulates its gene expression. Journal of Dairy Science. 101(8). 6730–6741. 40 indexed citations
3.
Kavanaugh, Devon, John O’Callaghan, Michelle Kilcoyne, et al.. (2015). The intestinal glycome and its modulation by diet and nutrition. Nutrition Reviews. 73(6). 359–375. 30 indexed citations
4.
O’Hagan, Anne Marie, et al.. (2015). Wave energy in Europe: Views on experiences and progress to date. PEARL (University of Plymouth). 14. 180–197. 37 indexed citations
5.
Gerlach, Jared Q., Michelle Kilcoyne, John O’Callaghan, et al.. (2014). Profiling temporal changes in bovine milk lactoferrin glycosylation using lectin microarrays. Food Chemistry. 165. 388–396. 23 indexed citations
6.
Kavanaugh, Devon, John O’Callaghan, Ludovica F. Buttó, et al.. (2013). Exposure of Bifidobacterium longum subsp. infantis to Milk Oligosaccharides Increases Adhesion to Epithelial Cells and Induces a Substantial Transcriptional Response. PLoS ONE. 8(6). e67224–e67224. 88 indexed citations
7.
Lane, Jonathan A., John O’Callaghan, Stephen D. Carrington, & Rita M. Hickey. (2013). Transcriptional response of HT-29 intestinal epithelial cells to human and bovine milk oligosaccharides. British Journal Of Nutrition. 110(12). 2127–2137. 50 indexed citations
8.
O’Callaghan, John, Avril Coghlan, Abdelhamid Abbas, et al.. (2012). Functional characterization of the polyketide synthase gene required for ochratoxin A biosynthesis in Penicillium verrucosum. International Journal of Food Microbiology. 161(3). 172–181. 32 indexed citations
9.
O’Callaghan, John & Paul W. O’Toole. (2011). Lactobacillus: Host–Microbe Relationships. Current topics in microbiology and immunology. 358. 119–154. 101 indexed citations
10.
Slattery, Leah, John O’Callaghan, G.F. Fitzgerald, Tom Beresford, & R. Paul Ross. (2010). Invited review: Lactobacillus helveticus—A thermophilic dairy starter related to gut bacteria. Journal of Dairy Science. 93(10). 4435–4454. 100 indexed citations
11.
O’Sullivan, Órla, John O’Callaghan, Amaia Sangrador‐Vegas, et al.. (2009). Comparative genomics of lactic acid bacteria reveals a niche-specific gene set. BMC Microbiology. 9(1). 50–50. 100 indexed citations
12.
Atoui, Ali, Florence Mathieu, John O’Callaghan, et al.. (2009). Cloning and characterization of novel methylsalicylic acid synthase gene involved in the biosynthesis of isoasperlactone and asperlactone in Aspergillus westerdijkiae. Fungal Genetics and Biology. 46(10). 742–749. 13 indexed citations
13.
Callanan, Michael, et al.. (2009). Exploitation of the diverse insertion sequence element content of dairy Lactobacillus helveticus starters as a rapid method to identify different strains. Journal of Microbiological Methods. 79(1). 32–36. 2 indexed citations
14.
Zámocký, Marcel, Christina Schümann, Christoph Sygmund, et al.. (2008). Cloning, sequence analysis and heterologous expression in Pichia pastoris of a gene encoding a thermostable cellobiose dehydrogenase from Myriococcum thermophilum. Protein Expression and Purification. 59(2). 258–265. 75 indexed citations
15.
O’Callaghan, John & Alan D. W. Dobson. (2006). Phylogenetic analysis of polyketide synthase genes fromAspergillus ochraceus. Mycotoxin Research. 22(2). 125–133. 2 indexed citations
16.
O’Callaghan, John & Alan D. W. Dobson. (2005). Molecular Characterization of Ochratoxin A Biosynthesis and Producing Fungi. Advances in applied microbiology. 58. 227–243. 6 indexed citations
17.
White, Sandra L., John O’Callaghan, & Alan D. W. Dobson. (2005). Cloning and molecular characterization ofPenicillium expansumgenes upregulated under conditions permissive for patulin biosynthesis. FEMS Microbiology Letters. 255(1). 17–26. 43 indexed citations
18.
O’Callaghan, John, et al.. (2002). Optimisation of the expression of a Trametes versicolor laccase gene in Pichia pastoris. Journal of Industrial Microbiology & Biotechnology. 29(2). 55–59. 56 indexed citations
19.
20.
O’Callaghan, John. (1988). Neurotypic and gliotypic proteins as biochemical markers of neurotoxicity. Neurotoxicology and Teratology. 10(5). 445–452. 78 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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