title: Molecular Analysis and Expression ofbapGene in Biofilm-Forming Multi-Drug-ResistantAcinetobacter baumannii.
abstract: Acinetobacter baumanniiis commonly resistant to nearly all antibiotics due to presence of antibiotic resistance genes and biofilm formation. In this study we determined the presence of certain antibiotic-resistance genes associated with biofilm production and the influence of low iron concentration on expression of the biofilm-associated protein gene (bap) in development of biofilm among multi-drug-resistantA. baumannii(MDRAB).
  
  
  
  Sixty-five MDRAB isolates from clinical samples were collected. Molecular typing was carried out by random amplified polymorphism DNA polymerase chain reaction (RAPD-PCR). Biofilm formation was assayed by the microtiter method.
  
  
  
  The sequence ofbapwas determined and deposited in the GenBank database (accession no. KR080550.1). Expression ofbapin the presence of low iron was analyzed by relative quantitative real time PCR (rqRT-PCR). Nearly half of the isolates belonged to RAPD-types A and B remaining were either small clusters or singleton. The results of biofilm formation revealed that 23 (35.4%), 18 (27.7%), 13 (20%), and 11 (16.9%) of the isolates had strong, moderate, weak, and no biofilm activities, respectively.ompAandcsuEgenes were detected in all, whilebapandblaPER-1were detected in 43 (66%) and 42 (64%) of the isolates that showed strong and moderate biofilm activities (p ≤ 0.05), respectively. Analysis ofbapexpression by rqRT-PCR revealed five isolates with four-fold bap overexpression in the presence of low iron concentration (20 µM).
  
  
  
  The results suggest thatbapoverexpression may influence biofilm formation in presence of low iron concentration.
authors.affiliation: Department of Microbiology and Virology, Kerman University of Medical Sciences, Kerman, Iran.
authors.forename: Omid
authors.initials: O
authors.lastname: Azizi
authors.affiliation: Department of Bacteriology, Pasteur institute of Iran, Tehran, Iran.
authors.forename: Fereshteh
authors.initials: F
authors.lastname: Shahcheraghi
authors.affiliation: Department of Microbiology and Virology, Kurdistan University of Medical Sciences, Kurdistan, Iran.
authors.forename: Himen
authors.initials: H
authors.lastname: Salimizand
authors.affiliation: Department of Microbiology, School of Medicine, Jahrom University of Medical Sciences, Jahrom, Iran.
authors.forename: Farzan
authors.initials: F
authors.lastname: Modarresi
authors.affiliation: Department of Microbiology and Virology, Kerman University of Medical Sciences, Kerman, Iran; Environmental Health Sciences and Engineering Research Center; Kerman University of Medical Sciences, Kerman, Iran; Research Center for Infectious Diseases and Tropical Medicine, Kerman University of Medical Sciences.
authors.forename: Mohammad Reza
authors.initials: MR
authors.lastname: Shakibaie
authors.affiliation: Department of Microbiology and Virology, Kerman University of Medical Sciences, Kerman, Iran.
authors.forename: Shahla
authors.initials: Sh
authors.lastname: Mansouri
authors.affiliation: Cellular & Molecular Research Center and Microbiology Department, Faculty of Medicine, Kurdistan University of Medical Sciences, Iran.
authors.forename: Rashid
authors.initials: R
authors.lastname: Ramazanzadeh
authors.affiliation: Department of Bacteriology, Pasteur institute of Iran, Tehran, Iran.
authors.forename: Farzad
authors.initials: F
authors.lastname: Badmasti
authors.affiliation: Department of Bacteriology, Pasteur institute of Iran, Tehran, Iran.
authors.forename: Vajihe
authors.initials: V
authors.lastname: Nikbin
keywords: Acinetobacter baumannii; Biofilm; Biofilm-associated Protein (bap); Iron; rqRT-PCR