Filamentous hemagglutinin adhesin FhaB limits A.baumannii biofilm formation

Front Biosci (Elite Ed). 2017 Mar 1;9(2):266-275. doi: 10.2741/e801.

Abstract

Increased resistance and survival, as well as immune evasion, play a significant role in the pathogenicity of Acinetobacter baumannii. Here, we report on the adhesion of the bacterium to epithelial cells and formation of biofilm on abiotic surfaces. We identificed autotransporter (AT) genes that encode homologues (Fha-like) of the two-partner secretion system (TPS) in A.baumannii (ATCC19606) which we designate as FhaB (exoprotein) and FhaC (transporter) and demonstrate that these novel genes, are under the control of distinct regulatable promoters within either the same (FhaBC) or two distinct (FhaB and FhaC) cells. The expression of this gene in outer membrane protein (OM) showed them to be deficient in the adherence to A546 cells. FhaB is involved in hydrophobicity of A. baumannii ATCC19606 while FhaBC is associated with biofilm formation. The vaccinogenic potential of FHA-like proteins offers use of these targets as novel therapeutic strategies to limit A.baumannii associated morbidity and mortality.

MeSH terms

  • Acinetobacter baumannii / genetics
  • Acinetobacter baumannii / pathogenicity*
  • Acinetobacter baumannii / physiology
  • Adhesins, Bacterial / chemistry
  • Adhesins, Bacterial / genetics
  • Adhesins, Bacterial / physiology*
  • Amino Acid Sequence
  • Bacterial Adhesion / genetics
  • Biofilms
  • Cloning, Molecular
  • Computational Biology
  • Conserved Sequence
  • Escherichia coli / genetics
  • Gene Expression Regulation, Bacterial
  • Hydrophobic and Hydrophilic Interactions
  • Recombinant Fusion Proteins
  • Sequence Alignment

Substances

  • Adhesins, Bacterial
  • Recombinant Fusion Proteins