Biomolecular NMR Assignments

, Volume 13, Issue 1, pp 91–95 | Cite as

1H, 13C and 15N resonance assignments and structure prediction of translation initiation factor 1 from Clostridium difficile

  • Faith Aguilar
  • Niaz Banaei
  • Yonghong ZhangEmail author


Clostridium difficile is a gram-positive, toxin-producing, anaerobic bacterium whose virulence factors and mechanisms of pathogenesis require further investigation. C. difficile infections (CDI) result in the severe and potentially fatal gastrointestinal diseases pseudomembranous colitis and toxic megacolon following extensive broad spectrum antibiotic treatment. The increasing C. difficile fatalities are a result of the bacteria’s growing antibiotic resistance and consequential CDI recurrence, which led to the unmet need for new CDI treatment. Bacterial protein synthesis is an essential metabolic process and an effective target for antibacterial agents. Translation initiation factor 1 from C. difficile (Cd-IF1) is the smallest of the three initiation factors that acts to establish the 30S initiation complex to initiate translation during protein biosynthesis. Here we report the complete NMR 1H, 13C and 15N chemical shift assignments of Cd-IF1 as the basis for NMR structure determination and interaction studies. Secondary structure analyses have identified five β-strands and one short α-helix arranged in the sequential order β1-β2-β3-α1-β4-β5, which is supported by 15N-{1H} heteroNOEs. The assigned chemical shifts were used to conduct structure prediction by CS-Rosetta. The predicted structure suggests that Cd-IF1 adopts the typical β-barrel structure and is composed of an oligomer-binding motif.


Clostridium difficile Translation initiation factor 1 (IF1) NMR assignments Protein structure prediction 



We would like to thank Dr. Kristin E. Cano for technical support and help with NMR experiments at UTHSCSA, Mr. Thomas Eubanks for NMR technical support at UTRGV. This work was supported by University of Texas Rio Grande Valley Internal Seed Research Program award (2017–2018). The Department of Chemistry at UTRGV is grateful for the generous support provided by a Departmental Grant from the Robert A. Welch Foundation (Grant No. BX-0048).

Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interest.


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© Springer Nature B.V. 2018

Authors and Affiliations

  1. 1.Department of ChemistryThe University of Texas Rio Grande ValleyEdinburgUSA
  2. 2.Department of PathologyStanford University School of MedicineStanfordUSA
  3. 3.Division of Infectious Diseases and Geographic Medicine, Department of MedicineStanford University School of MedicineStanfordUSA

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