Professor Daniel Walker
- Affiliate (School of Infection & Immunity)
email:
Daniel.Walker@glasgow.ac.uk
RB226 Level B2, III, Sir Graeme Davies Building, University Place, Glasgow G12 8TA
Research interests
We aim to develop highly selective and potent protein antibiotics (bacteriocins) for the treatment of chronic bacterial infections and for use in agricultural applications. In addition, we are interested in determining the mechanism of action of bacteriocins, studying fundamental aspects of membrane biogenesis in Gram-negative bacteria and deleloping cross-linking stratagies for structural proteomics.
Current research projects include:
- Protein antibiotics as novel therapeutic agents for the treatment of chronic biofilm-mediated infection.
- Harnessing bacteriocins active against bacterial plant pathogens.
- Mapping protein-protein interactions in the translocation and assembly module (TAM) complex involved in autotransporter biogenesis.
- Development of cross-linking strategies for structural proteomics
Publications
2024
Li, X., Cole, J., Vaughan, D. , Xiao, Y., Walker, D. and Wall, D. M. (2024) Stratifying macrophages based on their infectious burden identifies novel host targets for intervention during Crohn’s disease associated adherent-invasive Escherichia coli infection. Microbiology, 170(6), 001470. (doi: 10.1099/mic.0.001470) (PMID:38916198)
Gerasimidis, K. , Faqerah, N. and Walker, D. (2024) Escherichia coli and diet in development and treatment of non-communicable diseases. From hypothesis generation to causation and formulation of dietary recommendations. Alimentary Pharmacology and Therapeutics, (Accepted for Publication)
2023
Faqerah, N., Walker, D. and Gerasimidis, K. (2023) Review article: the complex interplay between diet and Escherichia coli in inflammatory bowel disease. Alimentary Pharmacology and Therapeutics, 58(10), pp. 984-1004. (doi: 10.1111/apt.17720) (PMID:37771255)
Premsuriya, J., Mosbahi, K., Atanaskovic, I., Kleanthous, C. and Walker, D. (2023) Outer membrane translocation of pyocins via the copper regulated TonB-dependent transporter CrtA. Biochemical Journal, 480(14), pp. 1035-1049. (doi: 10.1042/BCJ20220552) (PMID:37399084) (PMCID:PMC10422930)
Li, X., Ormsby, M. J. , Fallata, G., Meikle, L. M., Walker, D. , Xu, D. and Wall, D. M. (2023) PF-431396 hydrate inhibition of kinase phosphorylation during adherent-invasive Escherichia coli infection inhibits intra-macrophage replication and inflammatory cytokine release. Microbiology, 169(6), 001337. (doi: 10.1099/mic.0.001337) (PMID:37311220) (PMCID:PMC10333790)
2021
Carpena, N. , Richards, K., Bello Gonzalez, T. D. J., Bravo-Blas, A., Housden, N. G., Gerasimidis, K. , Milling, S. W.F. , Douce, G. , Malik, D. J. and Walker, D. (2021) Targeted delivery of narrow-spectrum protein antibiotics to the lower gastrointestinal tract in a murine model of Escherichia coli colonization. Frontiers in Microbiology, 12, 670535. (doi: 10.3389/fmicb.2021.670535) (PMID:34721311) (PMCID:PMC8551963)
Chai, R., Rooney, W. M. , Milner, J. J. and Walker, D. (2021) Challenges of using protein antibiotics for pathogen control. Pest Management Science, 77(9), pp. 3836-3840. (doi: 10.1002/ps.6312) (PMID:33527621)
Six, A., Mosbahi, K., Barge, M., Kleanthous, C., Evans, T. and Walker, D. (2021) Pyocin efficacy in a murine model of Pseudomonas aeruginosa sepsis. Journal of Antimicrobial Chemotherapy, 76(9), pp. 2317-2324. (doi: 10.1093/jac/dkab199) (PMID:34142136) (PMCID:PMC8361349)
2020
Wojnowska, M. and Walker, D. (2020) FusB energizes import across the outer membrane through direct interaction with its ferredoxin substrate. mBio, 11(5), e02081-20. (doi: 10.1128/mBio.02081-20) (PMID:33109756) (PMCID:PMC7593965)
Rooney, W. M. , Chai, R., Milner, J. L. and Walker, D. (2020) Bacteriocins targeting Gram-negative phytopathogenic bacteria: plantibiotics of the future. Frontiers in Microbiology, 11, 575981. (doi: 10.3389/fmicb.2020.575981) (PMCID:PMC7530242)
Atanaskovic, I., Mosbahi, K., Sharp, C., Housden, N. G., Kaminska, R., Walker, D. and Kleanthous, C. (2020) Targeted killing of Pseudomonas aeruginosa by pyocin G occurs via the hemin transporter hur. Journal of Molecular Biology, 432(13), pp. 3869-3880. (doi: 10.1016/j.jmb.2020.04.020) (PMID:32339530) (PMCID:PMC7322526)
Rooney, W. M. , Grinter, R. W., Correia, A., Walker, D. C. and Milner, J. J. (2020) Engineering bacteriocin-mediated resistance against the plant pathogen Pseudomonas syringae. Plant Biotechnology Journal, 18(5), pp. 1296-1306. (doi: 10.1111/pbi.13294) (PMID:31705720) (PMCID:PMC7152609)
Hulme, H. et al. (2020) Microbiome-derived carnitine mimics as novel mediators of gut-brain axis communication. Science Advances, 6(11), eaax6328. (doi: 10.1126/sciadv.aax6328) (PMID:32195337) (PMCID:PMC7065903)
Behrens, H. M. et al. (2020) Pyocin S5 import into Pseudomonas aeruginosa reveals a generic mode of bacteriocin transport. mBio, 11(2), e03230-19. (doi: 10.1128/mBio.03230-19) (PMID:32156826) (PMCID:PMC7064778)
Ormsby, M. et al. (2020) Propionic acid promotes the virulent phenotype of Crohn's disease-associated adherent-invasive Escherichia coli. Cell Reports, 30(7), 2297-2305.e5. (doi: 10.1016/j.celrep.2020.01.078) (PMID:32075765) (PMCID:PMC7034058)
2019
The University Court Of The University of Glasgow (2019) Bacterial pathogen derived resistance in plants. .
Rooney, W. M. , Wojnowska, M. and Walker, D. (2019) Draft genome sequence of the necrotrophic plant pathogenic bacterium Pectobacterium carotovorum subsp. carotovorum strain LMG 2410. Microbiology Resource Announcements, 8(31), e00614-19. (doi: 10.1128/MRA.00614-19) (PMID:31371540) (PMCID:PMC6675988)
Six, A., Krajangwong, S., Crumlish, M., Zadoks, R. N. and Walker, D. (2019) Galleria mellonella as an infection model for the multi-host pathogen Streptococcus agalactiae reflects hypervirulence of strains associated with human invasive disease. Virulence, 10(1), pp. 600-609. (doi: 10.1080/21505594.2019.1631660) (PMID:31230520) (PMCID:PMC6592362)
Irvine, S., Bunk, B., Bayes, H. K., Spröer, C., Connolly, J. P.R., Six, A., Evans, T. J. , Roe, A. J. , Overmann, J. and Walker, D. (2019) Genomic and transcriptomic characterization of Pseudomonas aeruginosa small colony variants derived from a chronic infection model. Microbial Genomics, 5(4), (doi: 10.1099/mgen.0.000262) (PMID:30920365) (PMCID:PMC6521587)
Grinter, R., Leung, P. M., Wijeyewickrema, L. C., Littler, D., Beckham, S., Pike, R. N., Walker, D. , Greening, C. and Lithgow, T. (2019) Protease-associated import systems are widespread in Gram-negative bacteria. PLoS Genetics, 15(10), e1008435. (doi: 10.1371/journal.pgen.1008435)
2018
Mosbahi, K., Wojnowska, M., Albalat, A. and Walker, D. (2018) Bacterial iron acquisition mediated by outer membrane translocation and cleavage of a host protein. Proceedings of the National Academy of Sciences of the United States of America, 115(26), pp. 6840-6845. (doi: 10.1073/pnas.1800672115) (PMID:29891657) (PMCID:PMC6042079)
2017
Josts, I., Stubenrauch, C. J., Vadlamani, G., Mosbahi, K., Walker, D. , Lithgow, T. and Grinter, R. (2017) The structure of a conserved domain of TamB reveals a hydrophobic β taco fold. Structure, 25(12), 1898-1906.e5. (doi: 10.1016/j.str.2017.10.002) (PMID:29129383) (PMCID:PMC5719984)
White, P. et al. (2017) Exploitation of an iron transporter for bacterial protein antibiotic import. Proceedings of the National Academy of Sciences of the United States of America, 114(45), pp. 12051-12056. (doi: 10.1073/pnas.1713741114) (PMID:29078392)
Behrens, H. M., Six, A., Walker, D. and Kleanthous, C. (2017) The therapeutic potential of bacteriocins as protein antibiotics. Emerging Topics in Life Sciences, 1(1), pp. 65-74. (doi: 10.1042/ETLS20160016)
2016
Grinter, R. et al. (2016) Structure of the bacterial plant-ferredoxin receptor FusA. Nature Communications, 7, 13308. (doi: 10.1038/ncomms13308) (PMID:27796364) (PMCID:PMC5095587)
Klein, A., Wojdyla, J. A., Joshi, A., Josts, I., McCaughey, L. C. , Housden, N. G., Kaminska, R., Byron, O. , Walker, D. and Kleanthous, C. (2016) Structural and biophysical analysis of nuclease protein antibiotics. Biochemical Journal, 473(18), pp. 2799-2812. (doi: 10.1042/bcj20160544) (PMID:27402794) (PMCID:PMC5264503)
McCaughey, L. C. , Josts, I., Grinter, R., White, P., Byron, O. , Tucker, N. P., Matthews, J. M., Kleanthous, C., Whitchurch, C. and Walker, D. (2016) Discovery, characterization and in vivo activity of pyocin SD2, a protein antibiotic from Pseudomonas aeruginosa. Biochemical Journal, 473(15), pp. 2345-2358. (doi: 10.1042/bcj20160470) (PMID:27252387) (PMCID:PMC4964976)
McCaughey, L. C., Ritchie, N. D., Douce, G. R. , Evans, T. J. and Walker, D. (2016) Efficacy of species-specific protein antibiotics in a murine model of acute Pseudomonas aeruginosa lung infection. Scientific Reports, 6, 30201. (doi: 10.1038/srep30201) (PMID:27444885) (PMCID:PMC4957109)
Ashraf, K. U., Josts, I., Mosbahi, K., Kelly, S. M. , Byron, O. , Smith, B. O. and Walker, D. (2016) The potassium binding protein Kbp is a cytoplasmic potassium sensor. Structure, 24(5), pp. 741-749. (doi: 10.1016/j.str.2016.03.017) (PMID:27112601)
Connolly, J. P. R., Gabrielsen, M. , Goldstone, R. J., Grinter, R., Wang, D., Cogdell, R. J. , Walker, D. , Smith, D. G. E. and Roe, A. J. (2016) A highly conserved bacterial d-serine uptake system links host metabolism and virulence. PLoS Pathogens, 12(1), e1005359. (doi: 10.1371/journal.ppat.1005359) (PMID:26727373) (PMCID:PMC4699771)
2015
Brown, C. L., Smith, K., Wall, D. and Walker, D. (2015) Activity of species-specific antibiotics against Crohnʼs disease–associated adherent-invasive Escherichia coli. Inflammatory Bowel Diseases, 21(10), pp. 2372-2382. (doi: 10.1097/MIB.0000000000000488) (PMID:26177305)
Joshi, A. et al. (2015) Structures of the ultra-high-affinity protein–protein complexes of pyocins S2 and AP41 and their cognate immunity proteins from pseudomonas aeruginosa. Journal of Molecular Biology, 427(17), pp. 2852-2866. (doi: 10.1016/j.jmb.2015.07.014) (PMID:26215615) (PMCID:PMC4548480)
Fyfe, C.D., Grinter, R., Josts, I., Mosbahi, K., Roszak, A.W., Cogdell, R.J. , Wall, D.M. , Burchmore, R.J.S. , Byron, O. and Walker, D. (2015) Structure of protease-cleaved escherichia coliα-2-macroglobulin reveals a putative mechanism of conformational activation for protease entrapment. Acta Crystallographica. Section D: Biological Crystallography, 71(7), pp. 1478-1486. (doi: 10.1107/s1399004715008548) (PMID:26143919) (PMCID:PMC4498604)
Papadakos, G., Sharma, A., Lancaster, L. E., Bowen, R., Kaminska, R., Leech, A. P., Walker, D. , Redfield, C. and Kleanthous, C. (2015) Consequences of inducing intrinsic disorder in a high-affinity protein–protein interaction. Journal of the American Chemical Society, 137(16), pp. 5252-5255. (doi: 10.1021/ja512607r) (PMID:25856265)
2014
Grinter, R., Josts, I., Zeth, K., Roszak, A. W., McCaughey, L. C. , Cogdell, R. J. , Milner, J. J. , Kelly, S. M., Byron, O. and Walker, D. (2014) Structure of the atypical bacteriocin pectocin M2 implies a novel mechanism of protein uptake. Molecular Microbiology, 93(2), pp. 234-246. (doi: 10.1111/mmi.12655) (PMID:24865810) (PMCID:PMC4671253)
McCaughey, L. C. et al. (2014) Lectin-like bacteriocins from Pseudomonas spp. utilise D-rhamnose containing lipopolysaccharide as a cellular receptor. PLoS Pathogens, 10(2), e1003898. (doi: 10.1371/journal.ppat.1003898) (PMID:24516380) (PMCID:PMC3916391)
Josts, I., Grinter, R., Kelly, S. M. , Mosbahi, K., Roszak, A., Cogdell, R. , Smith, B. O. , Byron, O. and Walker, D. (2014) Recombinant expression, purification, crystallization and preliminary X-ray diffraction analysis of the C-terminal DUF490963–1138 domain of TamB from Escherichia coli. Acta Crystallographica. Section F: Structural Biology Communications, 70(9), pp. 1272-1275. (doi: 10.1107/S2053230X14017403)
2013
Grinter, R., Milner, J. and Walker, D. (2013) Beware of proteins bearing gifts: protein antibiotics that use iron as a Trojan horse. FEMS Microbiology Letters, 338(1), pp. 1-9. (doi: 10.1111/1574-6968.12011)
Dunne, K.A. et al. (2013) Increased S-nitrosylation and proteasomal degradation of caspase-3 during infection contribute to the persistence of adherent invasive escherichia coli (AIEC) in immune cells. PLoS ONE, 8(7), e68386. (doi: 10.1371/journal.pone.0068386) (PMID:23861899) (PMCID:PMC3701656)
2012
Brown, C. L., Smith, K., McCaughey, L. and Walker, D. (2012) Colicin-like bacteriocins as novel therapeutic agents for the treatment of chronic biofilm-mediated infection. Biochemical Society Transactions, 40(6), pp. 1549-1552. (doi: 10.1042/BST20120241) (PMID:23176515)
Grinter, R., Milner, J. and Walker, D. (2012) Bacteriocins active against plant pathogenic bacteria. Biochemical Society Transactions, 40(6), pp. 1498-1502. (doi: 10.1042/BST20120206)
Penfold, C.N., Walker, D. and Kleanthous, C. (2012) How bugs kill bugs: progress and challenges in bacteriocin research. Biochemical Society Transactions, 40(6), pp. 1433-1437. (doi: 10.1042/BST20120253)
Grinter, R., Roszak, A.W., Cogdell, R.J. , Milner, J.J. and Walker, D. (2012) The crystal structure of the lipid II-degrading bacteriocin syringacin M suggests unexpected evolutionary relationships between colicin M-like bacteriocins. Journal of Biological Chemistry, 287(46), pp. 38876-38888. (doi: 10.1074/jbc.M112.400150)
Smith, K., Martin, L., Rinaldi, A., Rajendran, R., Ramage, G. and Walker, D. (2012) Activity of Pyocin S2 against Pseudomonas aeruginosa biofilms. Antimicrobial Agents and Chemotherapy, 56(3), pp. 1599-1601. (doi: 10.1128/AAC.05714-11)
Grinter, R., Milner, J. and Walker, D. (2012) Ferredoxin containing bacteriocins suggest a novel mechanism of iron uptake in Pectobacterium spp. PLoS ONE, 7(3), e33033. (doi: 10.1371/journal.pone.0033033) (PMID:22427936) (PMCID:PMC3302902)
Selkrig, J. et al. (2012) Discovery of an archetypal protein transport system in bacterial outer membranes. Nature Structural and Molecular Biology, 19(5), pp. 506-510. (doi: 10.1038/nsmb.2261)
2007
Walker, D., Moshbahi, K., Vankemmelbeke, M., James, R. and Kleanthous, C. (2007) The role of electrostatics in colicin nuclease domain translocation into bacterial cells. Journal of Biological Chemistry, 282, pp. 31389-31397. (doi: 10.1074/jbc.M705883200)
2006
Loftus, S., Walker, D., Mate, M., Bonsor, D., James, R., Moore, G. and Kleanthous, C. (2006) Competitive recruitment of the periplasmic translocation portal TolB by a natively disordered domain of colicin E9. Proceedings of the National Academy of Sciences of the United States of America, 103(33), pp. 12353-12358. (doi: 10.1073/pnas.0603433103)
Mosbahi, K., Walker, D., James, R., Moore, G. and Kleanthous, C. (2006) Global structural rearrangement of the cell penetrating ribonuclease colicin E3 on interaction with phospholipid membranes. Protein Science, 15, pp. 620-627. (doi: 10.1110/ps.051890306)
2004
Mosbahi, K., Walker, D., Lea, E., Moore, G., James, R. and Kleanthous, C. (2004) Destabilization of the colicin E9 endonuclease domain by interaction with negatively charged phospholipids - Implications for colicin translocation into bacteria. Journal of Biological Chemistry, 279, pp. 22145-22151. (doi: 10.1074/jbc.M400402200)
Walker, D., Lancaster, L., James, R. and Kleanthous, C. (2004) Identification of the catalytic motif of the microbial ribosome inactivating cytotoxin colicin E3. Protein Science, 13, pp. 1603-1611.
Walker, D., Rolfe, M., Thompson, A., Moore, G., James, R., Hinton, J. and Kleanthous, C. (2004) Transcriptional profiling of colicin-induced cell death of Escherichia coli MG1655 identifies potential mechanisms by which bacteriocins promote bacterial diversity. Journal of Bacteriology, 186, pp. 866-869. (doi: 10.1128/JB.186.3.866-869.2004)
2003
Law, C. J., Penfold, C. N., Walker, D. C. , Moore, G. R., James, R. and Kleanthous, C. (2003) OmpF enhances the ability of BtuB to protect susceptible Escherichia coli cells from colicin E9 cytotoxicity. FEBS Letters, 545(2-3), pp. 127-132. (doi: 10.1016/S0014-5793(03)00511-8)
Walker, D., Moore, G., James, R. and Kleanthous, C. (2003) Thermodynamic consequences of bipartite immunity protein binding to the ribosomal ribonuclease colicin E3. Biochemistry, 42, pp. 4161-4171. (doi: 10.1021/bi0273720)
2002
McEwan, A. G., Lewin, A., Davy, S. L., Boetzel, R., Leech, A., Walker, D., Wood, T. and Moore, G. R. (2002) PrrC from Rhodobacter sphaeroides, a homologue of eukaryotic Sco proteins, is a copper-binding protein and may have a thiol-disulfide oxidoreductase activity. FEBS Letters, 518(1-3), pp. 10-16. (doi: 10.1016/S0014-5793(02)02532-2)
McAllen, R., Walker, D. and Taylor, A. (2002) The environmental effects of salinity and temperature on the oxygen consumption and total body osmolality of the marine flatworm Procerodes littoralis. Journal of Experimental Marine Biology and Ecology, 268, pp. 103-113.
Walker, D., Georgiou, T., Pommer, A., Walker, D., Moore, G., Kleanthous, C. and James, R. (2002) Mutagenic scan of the H-N-H motif of colicin E9: implications for the mechanistic enzymology of colicins, homing enzymes and apoptotic endonucleases. Nucleic Acids Research, 30, pp. 3225-3234.
2001
Pommer, A.J. et al. (2001) Mechanism and cleavage specificity of the H-N-H endonuclease colicin E9. Journal of Molecular Biology, 314(4), pp. 735-749. (doi: 10.1006/jmbi.2001.5189)
Kleanthous, C. and Walker, D. (2001) Immunity proteins: enzyme inhibitors that avoid the active site. Trends in Biochemical Sciences, 26(10), pp. 624-631. (doi: 10.1016/S0968-0004(01)01941-7) (PMID:11590016)
Articles
Li, X., Cole, J., Vaughan, D. , Xiao, Y., Walker, D. and Wall, D. M. (2024) Stratifying macrophages based on their infectious burden identifies novel host targets for intervention during Crohn’s disease associated adherent-invasive Escherichia coli infection. Microbiology, 170(6), 001470. (doi: 10.1099/mic.0.001470) (PMID:38916198)
Gerasimidis, K. , Faqerah, N. and Walker, D. (2024) Escherichia coli and diet in development and treatment of non-communicable diseases. From hypothesis generation to causation and formulation of dietary recommendations. Alimentary Pharmacology and Therapeutics, (Accepted for Publication)
Faqerah, N., Walker, D. and Gerasimidis, K. (2023) Review article: the complex interplay between diet and Escherichia coli in inflammatory bowel disease. Alimentary Pharmacology and Therapeutics, 58(10), pp. 984-1004. (doi: 10.1111/apt.17720) (PMID:37771255)
Premsuriya, J., Mosbahi, K., Atanaskovic, I., Kleanthous, C. and Walker, D. (2023) Outer membrane translocation of pyocins via the copper regulated TonB-dependent transporter CrtA. Biochemical Journal, 480(14), pp. 1035-1049. (doi: 10.1042/BCJ20220552) (PMID:37399084) (PMCID:PMC10422930)
Li, X., Ormsby, M. J. , Fallata, G., Meikle, L. M., Walker, D. , Xu, D. and Wall, D. M. (2023) PF-431396 hydrate inhibition of kinase phosphorylation during adherent-invasive Escherichia coli infection inhibits intra-macrophage replication and inflammatory cytokine release. Microbiology, 169(6), 001337. (doi: 10.1099/mic.0.001337) (PMID:37311220) (PMCID:PMC10333790)
Carpena, N. , Richards, K., Bello Gonzalez, T. D. J., Bravo-Blas, A., Housden, N. G., Gerasimidis, K. , Milling, S. W.F. , Douce, G. , Malik, D. J. and Walker, D. (2021) Targeted delivery of narrow-spectrum protein antibiotics to the lower gastrointestinal tract in a murine model of Escherichia coli colonization. Frontiers in Microbiology, 12, 670535. (doi: 10.3389/fmicb.2021.670535) (PMID:34721311) (PMCID:PMC8551963)
Chai, R., Rooney, W. M. , Milner, J. J. and Walker, D. (2021) Challenges of using protein antibiotics for pathogen control. Pest Management Science, 77(9), pp. 3836-3840. (doi: 10.1002/ps.6312) (PMID:33527621)
Six, A., Mosbahi, K., Barge, M., Kleanthous, C., Evans, T. and Walker, D. (2021) Pyocin efficacy in a murine model of Pseudomonas aeruginosa sepsis. Journal of Antimicrobial Chemotherapy, 76(9), pp. 2317-2324. (doi: 10.1093/jac/dkab199) (PMID:34142136) (PMCID:PMC8361349)
Wojnowska, M. and Walker, D. (2020) FusB energizes import across the outer membrane through direct interaction with its ferredoxin substrate. mBio, 11(5), e02081-20. (doi: 10.1128/mBio.02081-20) (PMID:33109756) (PMCID:PMC7593965)
Rooney, W. M. , Chai, R., Milner, J. L. and Walker, D. (2020) Bacteriocins targeting Gram-negative phytopathogenic bacteria: plantibiotics of the future. Frontiers in Microbiology, 11, 575981. (doi: 10.3389/fmicb.2020.575981) (PMCID:PMC7530242)
Atanaskovic, I., Mosbahi, K., Sharp, C., Housden, N. G., Kaminska, R., Walker, D. and Kleanthous, C. (2020) Targeted killing of Pseudomonas aeruginosa by pyocin G occurs via the hemin transporter hur. Journal of Molecular Biology, 432(13), pp. 3869-3880. (doi: 10.1016/j.jmb.2020.04.020) (PMID:32339530) (PMCID:PMC7322526)
Rooney, W. M. , Grinter, R. W., Correia, A., Walker, D. C. and Milner, J. J. (2020) Engineering bacteriocin-mediated resistance against the plant pathogen Pseudomonas syringae. Plant Biotechnology Journal, 18(5), pp. 1296-1306. (doi: 10.1111/pbi.13294) (PMID:31705720) (PMCID:PMC7152609)
Hulme, H. et al. (2020) Microbiome-derived carnitine mimics as novel mediators of gut-brain axis communication. Science Advances, 6(11), eaax6328. (doi: 10.1126/sciadv.aax6328) (PMID:32195337) (PMCID:PMC7065903)
Behrens, H. M. et al. (2020) Pyocin S5 import into Pseudomonas aeruginosa reveals a generic mode of bacteriocin transport. mBio, 11(2), e03230-19. (doi: 10.1128/mBio.03230-19) (PMID:32156826) (PMCID:PMC7064778)
Ormsby, M. et al. (2020) Propionic acid promotes the virulent phenotype of Crohn's disease-associated adherent-invasive Escherichia coli. Cell Reports, 30(7), 2297-2305.e5. (doi: 10.1016/j.celrep.2020.01.078) (PMID:32075765) (PMCID:PMC7034058)
Rooney, W. M. , Wojnowska, M. and Walker, D. (2019) Draft genome sequence of the necrotrophic plant pathogenic bacterium Pectobacterium carotovorum subsp. carotovorum strain LMG 2410. Microbiology Resource Announcements, 8(31), e00614-19. (doi: 10.1128/MRA.00614-19) (PMID:31371540) (PMCID:PMC6675988)
Six, A., Krajangwong, S., Crumlish, M., Zadoks, R. N. and Walker, D. (2019) Galleria mellonella as an infection model for the multi-host pathogen Streptococcus agalactiae reflects hypervirulence of strains associated with human invasive disease. Virulence, 10(1), pp. 600-609. (doi: 10.1080/21505594.2019.1631660) (PMID:31230520) (PMCID:PMC6592362)
Irvine, S., Bunk, B., Bayes, H. K., Spröer, C., Connolly, J. P.R., Six, A., Evans, T. J. , Roe, A. J. , Overmann, J. and Walker, D. (2019) Genomic and transcriptomic characterization of Pseudomonas aeruginosa small colony variants derived from a chronic infection model. Microbial Genomics, 5(4), (doi: 10.1099/mgen.0.000262) (PMID:30920365) (PMCID:PMC6521587)
Grinter, R., Leung, P. M., Wijeyewickrema, L. C., Littler, D., Beckham, S., Pike, R. N., Walker, D. , Greening, C. and Lithgow, T. (2019) Protease-associated import systems are widespread in Gram-negative bacteria. PLoS Genetics, 15(10), e1008435. (doi: 10.1371/journal.pgen.1008435)
Mosbahi, K., Wojnowska, M., Albalat, A. and Walker, D. (2018) Bacterial iron acquisition mediated by outer membrane translocation and cleavage of a host protein. Proceedings of the National Academy of Sciences of the United States of America, 115(26), pp. 6840-6845. (doi: 10.1073/pnas.1800672115) (PMID:29891657) (PMCID:PMC6042079)
Josts, I., Stubenrauch, C. J., Vadlamani, G., Mosbahi, K., Walker, D. , Lithgow, T. and Grinter, R. (2017) The structure of a conserved domain of TamB reveals a hydrophobic β taco fold. Structure, 25(12), 1898-1906.e5. (doi: 10.1016/j.str.2017.10.002) (PMID:29129383) (PMCID:PMC5719984)
White, P. et al. (2017) Exploitation of an iron transporter for bacterial protein antibiotic import. Proceedings of the National Academy of Sciences of the United States of America, 114(45), pp. 12051-12056. (doi: 10.1073/pnas.1713741114) (PMID:29078392)
Behrens, H. M., Six, A., Walker, D. and Kleanthous, C. (2017) The therapeutic potential of bacteriocins as protein antibiotics. Emerging Topics in Life Sciences, 1(1), pp. 65-74. (doi: 10.1042/ETLS20160016)
Grinter, R. et al. (2016) Structure of the bacterial plant-ferredoxin receptor FusA. Nature Communications, 7, 13308. (doi: 10.1038/ncomms13308) (PMID:27796364) (PMCID:PMC5095587)
Klein, A., Wojdyla, J. A., Joshi, A., Josts, I., McCaughey, L. C. , Housden, N. G., Kaminska, R., Byron, O. , Walker, D. and Kleanthous, C. (2016) Structural and biophysical analysis of nuclease protein antibiotics. Biochemical Journal, 473(18), pp. 2799-2812. (doi: 10.1042/bcj20160544) (PMID:27402794) (PMCID:PMC5264503)
McCaughey, L. C. , Josts, I., Grinter, R., White, P., Byron, O. , Tucker, N. P., Matthews, J. M., Kleanthous, C., Whitchurch, C. and Walker, D. (2016) Discovery, characterization and in vivo activity of pyocin SD2, a protein antibiotic from Pseudomonas aeruginosa. Biochemical Journal, 473(15), pp. 2345-2358. (doi: 10.1042/bcj20160470) (PMID:27252387) (PMCID:PMC4964976)
McCaughey, L. C., Ritchie, N. D., Douce, G. R. , Evans, T. J. and Walker, D. (2016) Efficacy of species-specific protein antibiotics in a murine model of acute Pseudomonas aeruginosa lung infection. Scientific Reports, 6, 30201. (doi: 10.1038/srep30201) (PMID:27444885) (PMCID:PMC4957109)
Ashraf, K. U., Josts, I., Mosbahi, K., Kelly, S. M. , Byron, O. , Smith, B. O. and Walker, D. (2016) The potassium binding protein Kbp is a cytoplasmic potassium sensor. Structure, 24(5), pp. 741-749. (doi: 10.1016/j.str.2016.03.017) (PMID:27112601)
Connolly, J. P. R., Gabrielsen, M. , Goldstone, R. J., Grinter, R., Wang, D., Cogdell, R. J. , Walker, D. , Smith, D. G. E. and Roe, A. J. (2016) A highly conserved bacterial d-serine uptake system links host metabolism and virulence. PLoS Pathogens, 12(1), e1005359. (doi: 10.1371/journal.ppat.1005359) (PMID:26727373) (PMCID:PMC4699771)
Brown, C. L., Smith, K., Wall, D. and Walker, D. (2015) Activity of species-specific antibiotics against Crohnʼs disease–associated adherent-invasive Escherichia coli. Inflammatory Bowel Diseases, 21(10), pp. 2372-2382. (doi: 10.1097/MIB.0000000000000488) (PMID:26177305)
Joshi, A. et al. (2015) Structures of the ultra-high-affinity protein–protein complexes of pyocins S2 and AP41 and their cognate immunity proteins from pseudomonas aeruginosa. Journal of Molecular Biology, 427(17), pp. 2852-2866. (doi: 10.1016/j.jmb.2015.07.014) (PMID:26215615) (PMCID:PMC4548480)
Fyfe, C.D., Grinter, R., Josts, I., Mosbahi, K., Roszak, A.W., Cogdell, R.J. , Wall, D.M. , Burchmore, R.J.S. , Byron, O. and Walker, D. (2015) Structure of protease-cleaved escherichia coliα-2-macroglobulin reveals a putative mechanism of conformational activation for protease entrapment. Acta Crystallographica. Section D: Biological Crystallography, 71(7), pp. 1478-1486. (doi: 10.1107/s1399004715008548) (PMID:26143919) (PMCID:PMC4498604)
Papadakos, G., Sharma, A., Lancaster, L. E., Bowen, R., Kaminska, R., Leech, A. P., Walker, D. , Redfield, C. and Kleanthous, C. (2015) Consequences of inducing intrinsic disorder in a high-affinity protein–protein interaction. Journal of the American Chemical Society, 137(16), pp. 5252-5255. (doi: 10.1021/ja512607r) (PMID:25856265)
Grinter, R., Josts, I., Zeth, K., Roszak, A. W., McCaughey, L. C. , Cogdell, R. J. , Milner, J. J. , Kelly, S. M., Byron, O. and Walker, D. (2014) Structure of the atypical bacteriocin pectocin M2 implies a novel mechanism of protein uptake. Molecular Microbiology, 93(2), pp. 234-246. (doi: 10.1111/mmi.12655) (PMID:24865810) (PMCID:PMC4671253)
McCaughey, L. C. et al. (2014) Lectin-like bacteriocins from Pseudomonas spp. utilise D-rhamnose containing lipopolysaccharide as a cellular receptor. PLoS Pathogens, 10(2), e1003898. (doi: 10.1371/journal.ppat.1003898) (PMID:24516380) (PMCID:PMC3916391)
Josts, I., Grinter, R., Kelly, S. M. , Mosbahi, K., Roszak, A., Cogdell, R. , Smith, B. O. , Byron, O. and Walker, D. (2014) Recombinant expression, purification, crystallization and preliminary X-ray diffraction analysis of the C-terminal DUF490963–1138 domain of TamB from Escherichia coli. Acta Crystallographica. Section F: Structural Biology Communications, 70(9), pp. 1272-1275. (doi: 10.1107/S2053230X14017403)
Grinter, R., Milner, J. and Walker, D. (2013) Beware of proteins bearing gifts: protein antibiotics that use iron as a Trojan horse. FEMS Microbiology Letters, 338(1), pp. 1-9. (doi: 10.1111/1574-6968.12011)
Dunne, K.A. et al. (2013) Increased S-nitrosylation and proteasomal degradation of caspase-3 during infection contribute to the persistence of adherent invasive escherichia coli (AIEC) in immune cells. PLoS ONE, 8(7), e68386. (doi: 10.1371/journal.pone.0068386) (PMID:23861899) (PMCID:PMC3701656)
Brown, C. L., Smith, K., McCaughey, L. and Walker, D. (2012) Colicin-like bacteriocins as novel therapeutic agents for the treatment of chronic biofilm-mediated infection. Biochemical Society Transactions, 40(6), pp. 1549-1552. (doi: 10.1042/BST20120241) (PMID:23176515)
Grinter, R., Milner, J. and Walker, D. (2012) Bacteriocins active against plant pathogenic bacteria. Biochemical Society Transactions, 40(6), pp. 1498-1502. (doi: 10.1042/BST20120206)
Penfold, C.N., Walker, D. and Kleanthous, C. (2012) How bugs kill bugs: progress and challenges in bacteriocin research. Biochemical Society Transactions, 40(6), pp. 1433-1437. (doi: 10.1042/BST20120253)
Grinter, R., Roszak, A.W., Cogdell, R.J. , Milner, J.J. and Walker, D. (2012) The crystal structure of the lipid II-degrading bacteriocin syringacin M suggests unexpected evolutionary relationships between colicin M-like bacteriocins. Journal of Biological Chemistry, 287(46), pp. 38876-38888. (doi: 10.1074/jbc.M112.400150)
Smith, K., Martin, L., Rinaldi, A., Rajendran, R., Ramage, G. and Walker, D. (2012) Activity of Pyocin S2 against Pseudomonas aeruginosa biofilms. Antimicrobial Agents and Chemotherapy, 56(3), pp. 1599-1601. (doi: 10.1128/AAC.05714-11)
Grinter, R., Milner, J. and Walker, D. (2012) Ferredoxin containing bacteriocins suggest a novel mechanism of iron uptake in Pectobacterium spp. PLoS ONE, 7(3), e33033. (doi: 10.1371/journal.pone.0033033) (PMID:22427936) (PMCID:PMC3302902)
Selkrig, J. et al. (2012) Discovery of an archetypal protein transport system in bacterial outer membranes. Nature Structural and Molecular Biology, 19(5), pp. 506-510. (doi: 10.1038/nsmb.2261)
Walker, D., Moshbahi, K., Vankemmelbeke, M., James, R. and Kleanthous, C. (2007) The role of electrostatics in colicin nuclease domain translocation into bacterial cells. Journal of Biological Chemistry, 282, pp. 31389-31397. (doi: 10.1074/jbc.M705883200)
Loftus, S., Walker, D., Mate, M., Bonsor, D., James, R., Moore, G. and Kleanthous, C. (2006) Competitive recruitment of the periplasmic translocation portal TolB by a natively disordered domain of colicin E9. Proceedings of the National Academy of Sciences of the United States of America, 103(33), pp. 12353-12358. (doi: 10.1073/pnas.0603433103)
Mosbahi, K., Walker, D., James, R., Moore, G. and Kleanthous, C. (2006) Global structural rearrangement of the cell penetrating ribonuclease colicin E3 on interaction with phospholipid membranes. Protein Science, 15, pp. 620-627. (doi: 10.1110/ps.051890306)
Mosbahi, K., Walker, D., Lea, E., Moore, G., James, R. and Kleanthous, C. (2004) Destabilization of the colicin E9 endonuclease domain by interaction with negatively charged phospholipids - Implications for colicin translocation into bacteria. Journal of Biological Chemistry, 279, pp. 22145-22151. (doi: 10.1074/jbc.M400402200)
Walker, D., Lancaster, L., James, R. and Kleanthous, C. (2004) Identification of the catalytic motif of the microbial ribosome inactivating cytotoxin colicin E3. Protein Science, 13, pp. 1603-1611.
Walker, D., Rolfe, M., Thompson, A., Moore, G., James, R., Hinton, J. and Kleanthous, C. (2004) Transcriptional profiling of colicin-induced cell death of Escherichia coli MG1655 identifies potential mechanisms by which bacteriocins promote bacterial diversity. Journal of Bacteriology, 186, pp. 866-869. (doi: 10.1128/JB.186.3.866-869.2004)
Law, C. J., Penfold, C. N., Walker, D. C. , Moore, G. R., James, R. and Kleanthous, C. (2003) OmpF enhances the ability of BtuB to protect susceptible Escherichia coli cells from colicin E9 cytotoxicity. FEBS Letters, 545(2-3), pp. 127-132. (doi: 10.1016/S0014-5793(03)00511-8)
Walker, D., Moore, G., James, R. and Kleanthous, C. (2003) Thermodynamic consequences of bipartite immunity protein binding to the ribosomal ribonuclease colicin E3. Biochemistry, 42, pp. 4161-4171. (doi: 10.1021/bi0273720)
McEwan, A. G., Lewin, A., Davy, S. L., Boetzel, R., Leech, A., Walker, D., Wood, T. and Moore, G. R. (2002) PrrC from Rhodobacter sphaeroides, a homologue of eukaryotic Sco proteins, is a copper-binding protein and may have a thiol-disulfide oxidoreductase activity. FEBS Letters, 518(1-3), pp. 10-16. (doi: 10.1016/S0014-5793(02)02532-2)
McAllen, R., Walker, D. and Taylor, A. (2002) The environmental effects of salinity and temperature on the oxygen consumption and total body osmolality of the marine flatworm Procerodes littoralis. Journal of Experimental Marine Biology and Ecology, 268, pp. 103-113.
Walker, D., Georgiou, T., Pommer, A., Walker, D., Moore, G., Kleanthous, C. and James, R. (2002) Mutagenic scan of the H-N-H motif of colicin E9: implications for the mechanistic enzymology of colicins, homing enzymes and apoptotic endonucleases. Nucleic Acids Research, 30, pp. 3225-3234.
Pommer, A.J. et al. (2001) Mechanism and cleavage specificity of the H-N-H endonuclease colicin E9. Journal of Molecular Biology, 314(4), pp. 735-749. (doi: 10.1006/jmbi.2001.5189)
Kleanthous, C. and Walker, D. (2001) Immunity proteins: enzyme inhibitors that avoid the active site. Trends in Biochemical Sciences, 26(10), pp. 624-631. (doi: 10.1016/S0968-0004(01)01941-7) (PMID:11590016)
Patents
The University Court Of The University of Glasgow (2019) Bacterial pathogen derived resistance in plants. .
Grants
Grants and Awards listed are those received whilst working with the University of Glasgow.
- A platform technology for engineering therapeutic protein antibiotics
Medical Research Council
2022 - 2023
- Antimicrobial peptides as designer drugs
Medical Research Council
2022 - 2022
- Exploiting bacteriocins for plant protection against pathogenic bacteria
Biotechnology and Biological Sciences Research Council
2019 - 2021
- Targeted antibiotic therapy for highly drug-resistant lung infections in cystic fibrosis
Tenovus Scotland
2019 - 2020
- Precision targeting of the gut microbiome for the treatment of Inflammatory Bowel Disease and Autoimmune diseases
Scottish Enterprise
2017 - 2019
- Protein antibiotics for the treatment of Pseudomonas aeruginosa lung infection
Medical Research Council
2016 - 2019
- Protein Antibiotics: Discovery, mode of action and development
Wellcome Trust
2016 - 2021
- Precision targeting of the microbiome for the treatment of Crohn's disease
Scottish Enterprise
2016 - 2016
- CiC Precision engineering of the human gut microbiome
Medical Research Council
2016 - 2018
- Where and Why: The Influence of Host Metabolism on Bacterial Niche Specificity
Biotechnology and Biological Sciences Research Council
2016 - 2019
- Bacteria Combat; educational & interactive microbiology app
Society for Applied Microbiology
2015 - 2015
- A novel mechanism of protein uptake in Gram-negative bacteria
Biotechnology and Biological Sciences Research Council
2014 - 2018
- Confidence in Concept: Species-specific antibiotics for the treatment of bacterial infections
Medical Research Council
2014 - 2015
- Development of Colicins for the treatment of Crohn's disease.
Tenovus Scotland
2012 - 2013
- Antimicrobial activity of S-type pyocins against Pseudomonas aeruginosa in the biofilm state
Medical Research Scotland
2009 - 2011
- Role of YtfM in E.coli outer membrane assembly
Biotechnology and Biological Sciences Research Council
2009 - 2012
- Antimicrobial activity of S-type pyocins against Pseudomonas aeruginosa in the biofilm state
Tenovus Scotland
2008 - 2009
- Determining the kinetic mechanism and thermodynamic signature of binding induced protein folding
The Royal Society
2008 - 2009
Professional activities & recognition
Grant committees & research advisory boards
- 2015: BBSRC, Member of the BBSRC Pool of Experts