Surface-associated motility, a common trait of clinical isolates of Acinetobacter baumannii, depends on 1,3-diaminopropane

Abstract

Acinetobacter baumanniii -motility -1,3-diaminopropane -dat -ddc -A. baylyi ADP1 -52

Activities of Vancomycin-Containing Regimens against Colistin-Resistant Acinetobacter baumannii Clinical Strains

“…The G. mellonella infection model for studies of A. baumannii pathogenesis and therapeutics was initially reported by Peleg et al (20) and has subsequently been adopted by others (24)(25)(26)(27)(28). Among them, Hornsey et al (11) reported the efficacy of the COL-VAN combination in protecting G. mellonella from infection due to colistin-susceptible, carbap- enem-resistant A. baumannii strain AB210.…”

DNA Uptake by the Nosocomial Pathogen Acinetobacter baumannii Occurs during Movement along Wet Surfaces

“…In addition, spreading at the surface sometimes was found to be accompanied by the formation of ditches in the agar surface, and no signs of jerking movements were found by these authors under the conditions tested (27). Even though phenotypically distinct, all forms of motility described for A. baumannii have been shown to depend on synthesis of the polyamine 1,3-diaminopropane (26). Surface motility of A. baumannii was further shown to be controlled by blue light sensing (28) and quorum sensing (24,29) and to depend on iron availability (30,31).…”

“…Motility plates were composed of 0.5% agarose, 5 g/liter of tryptone, and 2.5 g/liter of NaCl as described previously (26). The inoculum was stabbed into the semisolid medium to enable spread of bacteria at both the surface of the medium and the interphase between the bottom of the petri dish and the medium.…”

“…Since that time, twitching motility has been intensively studied in many genera, including Myxococcus, Neisseria, Pseudomonas, and Haemophilus, firmly establishing that this form of movement is powered by depolymerization of type 4 pili (T4P) (18)(19)(20)(21). Only very recently was Acinetobacter motility further elucidated, providing evidence that at least in part it is driven by means of T4P in A. baumannii (22)(23)(24)(25)(26). Specifically, inactivation of pilT, putatively encoding an ATPase responsible for T4P retraction, reduced surface motility by roughly 50% (24).…”

“…Although an apparently complete set of genes required for natural transformation competence seems to be present in A. baumannii (23,25,37), to date, only a single isolate has been described to be naturally competent (13). Given the potential role of T4P in surface-associated motility of A. baumannii (17,(23)(24)(25)(26) and their established contribution to DNA uptake in various species (12,19,35), we speculated that A. baumannii might develop competence for DNA uptake while moving along wet surfaces in a T4P-dependent manner.…”