Kell's primary research interests are in systems biology, synthetic biology and computational biology.[2] He has also been involved in the development of multivariate scientific instrumentation and the attendant machine learning software (his first paper on artificial neural networks was in 1992). He has written extensively on the role of microbes as agents of supposedly 'non-communicable', chronic infectious diseases. His publications are mostly open access and are very widely cited, with an H-index at Google Scholar in excess of 130. According to Google Scholar[2] his most cited peer-reviewed research papers are in functional genomics,[17]metabolomics[18] and the yeast genome.[19] He has also been involved in research to create a robot scientist[20] in collaboration with Ross King, Stephen Muggleton and Steve Oliver, as well as several projects in systems biology.[21][22][23][24][25] He is involved in the study of membrane transporters, and their necessary involvement in the transmembrane uptake of pharmaceutical drugs.[26] He tends to choose scientific problems in which the prevailing orthodoxy is clearly incorrect. To this end, he has recently returned to the study of bioenergetics, summarising the detailed evidence against the prevailing wisdom of chemiosmotic coupling in oxidative and photosynthetic phosphorylation, replacing it with a protet-based model.[27][28]
With his collaborator Resia Pretorius, Kell discovered the amyloidogenic clotting of blood, involving the amyloidogenic self-assembly of the clotting protein fibrin into highly stable β-sheets that — unlike regular clots — are resistant to plasmin, the enzyme responsible for breaking up clots (fibrinolysis).[29] They report that such amyloidogenic clotting appears to be mostly caused by infectious agents, even in supposedly non-infectious diseases.[30] Kell and Pretorius report that such fibrin amyloid microclots (fibrinaloids) seem to be of major significance in long COVID.[31]
In 1988, he was a founding director of Aber Instruments, based at Aberystwyth Science Park (originally at the Centre for Alternative Technology (CAT), Machynlleth, Wales). In 2019 he was a co-founding director of Mellizyme Ltd, now Epoch Biodesign;[32] he left the company in 2023. He cofounded PhenUTest Ltd in 2021. He is an Associated Scientific Director of the Centre for Biosustainability at the Technical University of Denmark, where he runs the Flux Optimisation and Bioanalytics Group.
^Oliver, S. G.; Teusink, L. M.; Broadhurst, B.; Zhang, D.; Hayes, N.; Walsh, A.; Berden, M. C.; Brindle, J. A.; Kell, K. M.; Rowland, D. B.; Westerhoff, J. J.; Van Dam, H. V.; Oliver, K. (2001). "A functional genomics strategy that uses metabolome data to reveal the phenotype of silent mutations". Nature Biotechnology. 19 (1): 45–50. doi:10.1038/83496. PMID11135551. S2CID15491882.
^Goodacre, R.; Vaidyanathan, S.; Dunn, W. B.; Harrigan, G. G.; Kell, D. B. (2004). "Metabolomics by numbers: Acquiring and understanding global metabolite data". Trends in Biotechnology. 22 (5): 245–252. doi:10.1016/j.tibtech.2004.03.007. PMID15109811.
^Kell, Douglas B.; Pretorius, Etheresia (2017). "Proteins behaving badly. Substoichiometric molecular control and amplification of the initiation and nature of amyloid fibril formation: lessons from and for blood clotting". Prog. Biophys. Mol. Biol. 123: 6–41. doi:10.1016/j.pbiomolbio.2016.08.006. hdl:2263/59001. PMID27554450.