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Dr Karrera Djoko's Outputs (37)

The Role of Copper and Zinc Toxicity in Innate Immune Defense against Bacterial Pathogens (2015)
Journal Article
Djoko, K. Y., Ong, C. Y., Walker, M. J., & McEwan, A. G. (2015). The Role of Copper and Zinc Toxicity in Innate Immune Defense against Bacterial Pathogens. Journal of Biological Chemistry, 290(31), 18954-18961. https://doi.org/10.1074/jbc.r115.647099

Zinc (Zn) and copper (Cu) are essential for optimal innate immune function, and nutritional deficiency in either metal leads to increased susceptibility to bacterial infection. Recently, the decreased survival of bacterial pathogens with impaired Cu... Read More about The Role of Copper and Zinc Toxicity in Innate Immune Defense against Bacterial Pathogens.

A genetic screen reveals a periplasmic copper chaperone required for nitrite reductase activity in pathogenic Neisseria (2015)
Journal Article
Jen, F. C., Djoko, K., Bent, S., Day, C., McEwan, A., & Jennings, M. (2015). A genetic screen reveals a periplasmic copper chaperone required for nitrite reductase activity in pathogenic Neisseria. FASEB Journal, 29(9), 3828-3838. https://doi.org/10.1096/fj.15-270751

Under conditions of low oxygen availability, Neisseria meningitidis and Neisseria gonorrhoeae are able to respire via a partial denitrification pathway in which nitrite is converted to nitrous oxide. In this process, nitrite reductase (AniA), a coppe... Read More about A genetic screen reveals a periplasmic copper chaperone required for nitrite reductase activity in pathogenic Neisseria.

Inhibition of respiratory Complex I by copper(ii)-bis(thiosemicarbazonato) complexes (2014)
Journal Article
Djoko, K. Y., Donnelly, P. S., & McEwan, A. G. (2014). Inhibition of respiratory Complex I by copper(ii)-bis(thiosemicarbazonato) complexes. Metallomics, 6(12), 2250-2259. https://doi.org/10.1039/c4mt00226a

Several copper(II) complexes of bis(thiosemicarbazones) [Cu(btsc)s] show promise as therapeutics for the treatment of neurological diseases, cancers and bacterial infections. These complexes are thought to act primarily as copper ionophores or “coppe... Read More about Inhibition of respiratory Complex I by copper(ii)-bis(thiosemicarbazonato) complexes.

A Role for Lactate Dehydrogenases in the Survival of Neisseria gonorrhoeae in Human Polymorphonuclear Leukocytes and Cervical Epithelial Cells (2014)
Journal Article
Atack, J. M., Ibranovic, I., Ong, C. Y., Djoko, K. Y., Chen, N. H., vanden Hoven, R., …McEwan, A. G. (2014). A Role for Lactate Dehydrogenases in the Survival of Neisseria gonorrhoeae in Human Polymorphonuclear Leukocytes and Cervical Epithelial Cells. The Journal of Infectious Diseases, 210(8), 1311-1318. https://doi.org/10.1093/infdis/jiu230

Lactate is an abundant metabolite, produced by host tissues and commensal organisms, and it represents an important potential carbon source for bacterial pathogens. In the case of Neisseria spp., the importance of the lactate permease in colonization... Read More about A Role for Lactate Dehydrogenases in the Survival of Neisseria gonorrhoeae in Human Polymorphonuclear Leukocytes and Cervical Epithelial Cells.

Antimicrobial effects of copper(II) bis(thiosemicarbazonato) complexes provide new insight into their biochemical mode of action (2014)
Journal Article
Djoko, K. Y., Paterson, B. M., Donnelly, P. S., & McEwan, A. G. (2014). Antimicrobial effects of copper(II) bis(thiosemicarbazonato) complexes provide new insight into their biochemical mode of action. Metallomics, 6(4), 854-863. https://doi.org/10.1039/c3mt00348e

The copper(II) complexes of bis-thiosemicarbazones (Cu(btsc)) such as Cu(atsm) and Cu(gtsm) are neutral, lipophilic compounds that show promise as therapeutics for the treatment of certain neurological diseases and cancers. Although the effects of th... Read More about Antimicrobial effects of copper(II) bis(thiosemicarbazonato) complexes provide new insight into their biochemical mode of action.

Antimicrobial Action of Copper Is Amplified via Inhibition of Heme Biosynthesis. (2013)
Journal Article
Djoko, K. Y., & McEwan, A. G. (2013). Antimicrobial Action of Copper Is Amplified via Inhibition of Heme Biosynthesis. ACS Chemical Biology, 8(10), 2217-2223. https://doi.org/10.1021/cb4002443

Copper (Cu) is a potent antimicrobial agent. Its use as a disinfectant goes back to antiquity, but this metal ion has recently emerged to have a physiological role in the host innate immune response. Recent studies have identified iron–sulfur contain... Read More about Antimicrobial Action of Copper Is Amplified via Inhibition of Heme Biosynthesis..

Characterization of an ntrX Mutant of Neisseria gonorrhoeae Reveals a Response Regulator That Controls Expression of Respiratory Enzymes in Oxidase-Positive Proteobacteria (2013)
Journal Article
Atack, J. M., Srikhanta, Y. N., Djoko, K. Y., Welch, J. P., Hasri, N. H. M., Steichen, C. T., Vanden Hoven, R. N., Grimmond, S. M., Othman, D. S. M. P., Kappler, U., Apicella, M. A., Jennings, M. P., Edwards, J. L., & McEwan, A. G. (2013). Characterization of an ntrX Mutant of Neisseria gonorrhoeae Reveals a Response Regulator That Controls Expression of Respiratory Enzymes in Oxidase-Positive Proteobacteria. Journal of Bacteriology, 195(11), 2632-2641. https://doi.org/10.1128/jb.02062-12

NtrYX is a sensor-histidine kinase/response regulator two-component system that has had limited characterization in a small number of Alphaproteobacteria. Phylogenetic analysis of the response regulator NtrX showed that this two-component system is e... Read More about Characterization of an ntrX Mutant of Neisseria gonorrhoeae Reveals a Response Regulator That Controls Expression of Respiratory Enzymes in Oxidase-Positive Proteobacteria.

A Glutathione-Dependent Detoxification System Is Required for Formaldehyde Resistance and Optimal Survival ofNeisseria meningitidisin Biofilms (2012)
Journal Article
Chen, N. H., Couñago, R. M., Djoko, K. Y., Jennings, M. P., Apicella, M. A., Kobe, B., & McEwan, A. G. (2013). A Glutathione-Dependent Detoxification System Is Required for Formaldehyde Resistance and Optimal Survival ofNeisseria meningitidisin Biofilms. Antioxidants and Redox Signaling, 18(7), 743-755. https://doi.org/10.1089/ars.2012.4749

Aim: The glutathione-dependent AdhC-EstD formaldehyde detoxification system is found in eukaryotes and prokaryotes. It is established that it confers protection against formaldehyde that is produced from environmental sources or methanol metabolism.... Read More about A Glutathione-Dependent Detoxification System Is Required for Formaldehyde Resistance and Optimal Survival ofNeisseria meningitidisin Biofilms.

Phenotypic Characterization of a copA Mutant of Neisseria gonorrhoeae Identifies a Link between Copper and Nitrosative Stress (2011)
Journal Article
Djoko, K., Franiek, J., Edwards, J., Falsetta, M., Kidd, S., Potter, A., …McEwan, A. (2012). Phenotypic Characterization of a copA Mutant of Neisseria gonorrhoeae Identifies a Link between Copper and Nitrosative Stress. Infection and Immunity, 80(3), 1065-1071. https://doi.org/10.1128/iai.06163-11

NGO0579 is annotated copA in the Neisseria gonorrhoeae chromosome, suggesting that it encodes a cation-transporting ATPase specific for copper ions. Compared to wild-type cells, a copA mutant was more sensitive to killing by copper ions but not to ot... Read More about Phenotypic Characterization of a copA Mutant of Neisseria gonorrhoeae Identifies a Link between Copper and Nitrosative Stress.

Novel Bacterial MerR-Like Regulators: Their Role in the Response to Carbonyl and Nitrosative Stress (2011)
Book Chapter
McEwan, A. G., Djoko, K. Y., Chen, N. H., Couñago, R. L., Kidd, S. P., Potter, A. J., & Jennings, M. P. (2011). Novel Bacterial MerR-Like Regulators: Their Role in the Response to Carbonyl and Nitrosative Stress. In Advances in Microbial Physiology (1-22). https://doi.org/10.1016/b978-0-12-381043-4.00001-5

Recognition of the diversity of transcriptional regulators of the MerR family has increased considerably over the last decade and it has been established that not all MerR-like regulators are involved in metal ion recognition. A new type of MerR-like... Read More about Novel Bacterial MerR-Like Regulators: Their Role in the Response to Carbonyl and Nitrosative Stress.