Antigenic Properties of Iron Regulated Proteins in Acinetobacter baumannii: An In Silico Approach

  • Hadise Bazmara
  • Iraj RasooliEmail author
  • Abolfazl Jahangiri
  • Fatemeh Sefid
  • Shakiba Darvish Alipour Astaneh
  • Zahra Payandeh


Acinetobacter baumannii, an emerging nosocomial pathogen, causes multi-drug and pan-drug resistant infections. This phenomenon necessitates the development of new treatment strategies or vaccines against this pathogen. Iron acquisition systems are important factors for the virulence of pathogenic organisms. Antibodies against iron regulated outer membrane proteins (IROMPs) showed bactericidal and opsonizing activities against A. baumannii in vitro. Data obtained from proteomic studies could be valuable for vaccine design. Comparative proteomic analysis of total lysate and outer membrane fractions isolated from A. baumannii ATCC 19606 cells cultured under iron-rich and chelated conditions resulted in the identification of protein spots differentially produced. Need for bioinformatic tools is imperative for analysis of these data as well as to design novel proteins bearing desired properties. This study undertakes in silico identification of the most effective immunogenic target amongst these iron regulated proteins in A. baumannii which can be employed as a vaccine candidate. Here a screening was carried out on iron- regulated A. baumannii OMPs, based on hydrophilicity, flexibility, beta-turns, solubility and overall antigenic probability. 3D structure of the proteins was modeled. Linear and conformational B cell epitopes predicted and their densities were used for comparison of their immunogenicity. CarO was selected as an efficient immunogenic IROMP in A. baumannii which contributes to sidrophore mediated iron uptake.


A. baumanni IROMPs Immunogenicity Epitope density Bioinformatics 3D structure 



The authors wish to thank National Institute for Medical Research Development (NIMAD) Grant No. 958302 and Shahed University for their support to conduct the present study.

Compliance with Ethical Standards

Conflict of interest

We declare no conflict of interests.

Ethical Approval

This article does not contain any studies with human participants or animals performed by any of the authors.


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Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2017

Authors and Affiliations

  • Hadise Bazmara
    • 1
  • Iraj Rasooli
    • 1
    • 2
    Email author
  • Abolfazl Jahangiri
    • 1
    • 3
  • Fatemeh Sefid
    • 4
  • Shakiba Darvish Alipour Astaneh
    • 5
  • Zahra Payandeh
    • 6
  1. 1.Department of BiologyShahed UniversityTehranIran
  2. 2.Molecular Microbiology Research CenterShahed UniversityTehranIran
  3. 3.Applied Microbiology Research CenterBaqiyatallah University of Medical SciencesTehranIran
  4. 4.Department of BiologyScience and Art UniversityYazdIran
  5. 5.Department of BiotechnologySemnan UniversitySemnanIran
  6. 6.Department of Medical Biotechnology and Nanotechnology, Faculty of MedicineZanjan University of Medical SciencesZanjanIran

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