Adherence and motility characteristics of clinical Acinetobacter baumannii isolates

Abstract

Acinetobacter baumannii continues to be a major health problem especially in hospital settings. Herein, features that may play a role in persistence and disease potential were investigated in a collection of clinical A. baumannii strains from Australia. Twitching motility was found to be a common trait in A. baumannii international clone I strains and in abundant biofilm formers, whereas swarming motility was only observed in isolates not classified within the international clone lineages. Bioinformatic analysis of the type IV fimbriae revealed a correlation between PilA sequence homology and motility. A high level of variability in adherence to both abiotic surfaces and epithelial cells was found. We report for the first time the motility characteristics of a large number of A. baumannii isolates and present a direct comparison of A. baumannii binding to nasopharyngeal and lung epithelial cells.

Virulence Factors of Acinetobacter baumannii Environmental Isolates and Their Inhibition by Natural Zeolite

“…4) The 24 isolates of A. baumannii recovered from different stages of secondary type municipal wastewater treatment, both antibiotics-sensitive and MDR, showed different expression of the virulence factors that may contribute to its pathogenesis and survival in the natural environment. Ability of the expression of biofilm and pellicle formation, swarming and twitching motility was comparable to those of clinical isolates described in many literature reports (Antunes et al, 2011;Eijkelkamp et al, 2011a;Espinal et al, 2012;Marti et al, 2011;Nait Chabane et al, 2014).…”

“…Swarming and twitching motility were confirmed to be independent phenotypic parameters. Twitching motility was found to be a common trait of clinical strains of A. baumannii which are high biofilm formers (Eijkelkamp et al, 2011a). In this study no correlation of twitching motility and biofilm formation was detected.…”

“…A. baumannii is considered to be non-motile in liquid media due to the absence of flagella, but surface motility on solid/semisolid media was described. Two distinct forms of phenotypic surface motility of A. baumannii are recognized: twitching defined as surface translocation on solid surfaces and swarming defined as surface translocation on the semisolid media (Antunes et al, 2011;Eijkelkamp et al, 2011a). Twitching motility is considered as an important step in colonization and subsequent biofilm formation on medical devices, which is one of the main sources of hospital infections with A. baumannii.…”

Self-organization of bacterial biofilms is facilitated by extracellular DNA

“…Interestingly, interstitial biofilms of nontypeable Haemophilus influenzae and Acinetobacter baumanii that also actively expand via twitching motility (32,33) are not associated with the formation of intricate network patterns of trails despite the presence of eDNA in these biofilms (Fig. S9).…”

Structure of a short-chain dehydrogenase/reductase (SDR) within a genomic island from a clinical strain ofAcinetobacter baumannii

“…A draft genome sequence of the Australian strain A. baumannii WM99c, isolated from a hospital patient in Sydney (Valenzuela et al, 2007), has recently been described (Eijkelkamp et al, 2011). At the time of sequencing, our multi-way BLAST analysis identified 20 GIs, accounting for 16% of the WM99c genome.…”