Samir Elqaidi

Molecular Microbiologist with 18 years of experience, specializing in bacterial genetic, metabolic and virulence genes regulation, nucleic acid manipulation, molecular cloning, point mutagenesis, and genome editing. I earned my Ph.D. from the University Pierre et Marie Curie, Paris, and conducted significant research on bacterial gene regulation. During my career, I made a breakthrough discovery at Kansas State University, demonstrating the intra-bacterial activity of the type three secretion system.

• Pilot project, NIH Center on Emerging and Zoonotic Infectious Diseases (CEZID), Impact of SseK1 on bacterial gene regulation mediated by NagC and CRP, 2021-2023, $100,000
• R21 AI168453, T3SS Effector Regulation of Bacterial Metabolism, 2022, $410,000
• CVM SUCCESS FYI Intramural Grant Program (KSU), Use of bacterial glyoxalases for Methylglyoxal detoxification in diabetic mice, 2022, $15,000
• R03 AI165428, Bacterial Targets of T3SS Effector Proteases, 2021, $144,000

• STD NMR Epitope Perturbation by Mutation Unveils the Mechanism of YM155 as an Arginine-Glycosyltransferases Inhibitor Effective in Treating Enteropathogenic Diseases., Ramírez-Cárdenas J, Taleb V, Calvaresi V, Struwe WB, El Qaidi S, Zhu C, Hasan K, Zhang Y, Hardwidge PR, Veloz B, Muñoz-García JC, Hurtado-Guerrero R, Angulo J., 2025, JACS Au
• Fructose-1-kinase Has Pleiotropic Roles in Escherichia coli., Weeramange C, Menjivar C, O'Neil PT, El Qaidi S, Harrison KS, Meinhardt S, Bird CL, Sreenivasan S, Hardwidge PR, Fenton AW, Hefty PS, Bose JL, Swint-Kruse L., 2024, J Biol Chem
• Loss to gain: pseudogenes in microorganisms, focusing on eubacteria, and their biological significance., Yang Y, Wang P, Qaidi SE, Hardwidge PR, Huang J, Zhu G., 2024, Appl Microbiol Biotechnol
• Salmonella T3SS effector SseK1 arginine-glycosylates the two-component response regulator OmpR to alter bile salt resistance., Hasan, M. K., Scott, N. E., Hays, M. P., Hardwidge, P. R., and El Qaidi, S
• ., 2023, Scientific Reports
• Arginine glycosylation regulates UDP-GlcNAc biosynthesis in Salmonella enterica., El Qaidi, S., Scott, N. E., Hays, M. P., and Hardwidge, P. R., 2022, Scientific reports
• Repurposing avasimibe to inhibit bacterial glycosyltransferases., Hasan, M. K., El Qaidi, S., Peter McDonald., Anuradha Roy., and Hardwidge, P. R., 2022, Pathogens
• YM155 Inhibits NleB and SseK Arginine Glycosyltransferase Activity., Zhu, C., El Qaidi, S., McDonald, P., Roy, A., and Hardwidge, P. R., 2021, Pathogens
• The T3SS Effector Protease NleC Is Active within Citrobacter rodentium., Hasan, M. K., El Qaidi, S., and Hardwidge, P. R., 2021, Pathogens
• NleB/SseK-catalyzed arginine-glycosylation and enteropathogen virulence are finely tuned by a single variable position contiguous to the catalytic machinery., García-García, A., Hicks, T., El Qaidi, S., Zhu, C., Hardwidge, P. R., Angulo, J., and Hurtado-Guerrero, R., 2021, Chemical Science
• Arginine glycosylation enhances methylglyoxal detoxification., El Qaidi, S., Scott, N. E., and Hardwidge, P. R., 2021, Scientific reports
• Rapid detection of flagellated and non-flagellated Salmonella by targeting the common flagellar hook gene flgE., Yang, Y., Wang, P., Xia, P., Yang, B., Dai, P., Hong, T., Li, J., Meng, X., El Qaidi, S., and Zhu, G., 2020, Applied microbiology and biotechnology
• An intra-bacterial activity for a T3SS effector., El Qaidi, S., Scott, N. E., Hays, M. P., Geisbrecht, B. V., Watkins, S., and Hardwidge, P. R., 2020, Scientific reports
• ABC cloning: An efficient, simple, and rapid restriction/ligase-free method., El Qaidi, S. E
• ., and Hardwidge, P. R., 2019, MethodsX
• SseL Deubiquitinates RPS3 to Inhibit Its Nuclear Translocation., Wu, M., El Qaidi, S., and Hardwidge, P. R., 2018, Pathogens (Basel, Switzerland)
• Structural basis for arginine glycosylation of host substrates by bacterial effector proteins., Park, J. B., Kim, Y. H., Yoo, Y., Kim, J., Jun, S. H., Cho, J. W., El Qaidi, S., Walpole, S., Monaco, S., Garcia-Garcia, A. A., Wu, M., Hays, M. P., Hurtado-Guerrero, R., Angulo, J., Hardwidge, P. R., Shin, J. S., and Cho, H. S., 2018, Nature communications
• High-Throughput Screening for Bacterial Glycosyltransferase Inhibitors., El Qaidi, S., Zhu, C., McDonald, P., Roy, A., Maity, P. K., Rane, D., Perera, C., and Hardwidge, P. R., 2018, Frontiers in cellular and infection microbiology
• Salmonella, E. coli, and Citrobacter Type III Secretion System Effector Proteins that Alter Host Innate Immunity., El Qaidi, S., Wu, M., Zhu, C., and Hardwidge, P. R., 2018, Advances in experimental medicine and biology
• NleB/SseK effectors from Citrobacter rodentium, Escherichia coli, and Salmonella enterica display distinct differences in host substrate specificity., El Qaidi, S., Chen, K., Halim, A., Siukstaite, L., Rueter, C., Hurtado-Guerrero, R., Clausen, H., and Hardwidge, P. R., 2017, The Journal of biological chemistry
• The vitamin B(6) biosynthesis pathway in Streptococcus pneumoniae is controlled by pyridoxal 5'-phosphate and the transcription factor PdxR and has an impact on ear infection., El Qaidi, S., Yang, J., Zhang, J. R., Metzger, D. W., and Bai, G., 2013, Journal of bacteriology
• The phosphotransferase VanU represses expression of four qrr genes antagonizing VanO-mediated quorum-sensing regulation in Vibrio anguillarum., Weber, B., Lindell, K., El Qaidi, S., Hjerde, E., Willassen, N. P., and Milton, D. L., 2011, Microbiology (Reading)
• Repression of galP, the galactose transporter in Escherichia coli, requires the specific regulator of N-acetylglucosamine metabolism., El Qaidi, S., Allemand, F., Oberto, J., and Plumbridge, J., 2009, Molecular microbiology
• Switching control of expression of ptsG from the Mlc regulon to the NagC regulon., El Qaidi, S., and Plumbridge, J., 2008, Journal of bacteriology

• Review Editor, Molecular Bacterial Pathogenesis (Specialty section of Frontiers in Cellular and Infection Microbiology), Reviewing and editing manuscripts related to molecular bacterial pathogenesis., Contributing to editorial decisions and peer review processes.
• Review Editor, International Journal of Microbiology and Biotechnology, Reviewing and evaluating manuscripts focused on microbiology and biotechnology., Participating in the peer review process and providing feedback to authors and the editorial team.

Shelby Watkins, 2018-2019, Kristina Eichhorst, 2019-2020, Congrui Zhu, 2018-2021, Md Kamrul Hassan, 2019-2023