Isolation and Characterization of Acinetobacter baumannii Recovered from Campylobacter Selective Medium

Abstract

Acinetobacter baumannii, a Gram-negative opportunistic pathogen, is known to cause multidrug resistant infections. This organism has primarily been isolated from clinical environments and its environmental reservoirs remain largely unknown. In the present study, we recovered seven isolates of A. baumannii growing under conditions selective for Campylobacter spp. (microaerophilic at 42°C and in the presence of antibiotics) from dairy cattle manure storage tank or surface water impacted by livestock effluents. Antibiotic susceptibility tests revealed that all of these isolates were less susceptible to at least two different clinically relevant antibiotics, compared to the type strain A. baumannii ATCC17978. Expression of resistance-nodulation-division efflux pumps, an important mechanism of intrinsic resistance in these organisms, was analyzed, and adeB was found to be overexpressed in one and adeJ was overexpressed in three isolates. Comparison of these isolates using genomic DNA Macro-Restriction Fragment Pattern Analysis (MRFPA) revealed relatively low relatedness among themselves or with some of the clinical isolates from previous studies. This study suggests that A. baumannii isolates are capable of growing under selective conditions for Campylobacter spp. and that this organism can be present in manure and water.

Distribution and Genotyping of Aquatic Acinetobacter baumannii Strains Isolated from the Puzi River and Its Tributaries Near Areas of Livestock Farming

“…The results indicated that this pathogen occurred more frequently during the summer in aquatic environments. This observation is in accordance with the results of previous studies, which have suggested that A. baumannii is strictly aerobic and thermotropic (37-42 • C) [6,21,38]. Furthermore, another study suggested that, during the past decade, the prevalence of this pathogen in hospitals was higher between July and October than between January and June [39].…”

Occurrence, distribution and virulence factors of clinically important Acinetobacter species recovered from selected freshwater resources in the Eastern Cape Province, South Africa

“…Likewise, Krizova et al [28], noted a widespread of A. bohemicus in the water environment in the Czech Republic. A. baumannii was characterized from a surface water resources in South Nation River (SNR) drainage basin in Eastern Ontario, Canada, in 2013 [26]. Besides, the composition of the bacterial community in a freshwater aquaculture environment was investigated in China by [29].…”

“…As a result, an investigation of the occurrence and distribution of these clinically-important Acinetobacter species in other environments, other than hospital, is very necessary for the understanding of what nature and diversity truly represent [25,26]. As such, the time has come to redefine the environmental coverage by these organisms, beyond a clinical setting.…”

Occurrence, distribution and virulence factors of clinically important Acinetobacter species recovered from selected freshwater resources in the Eastern Cape Province, South Africa

“…As a result, an investigation of the occurrence and distribution of these pathogens in other environments, other than hospital, is very necessary for the understanding of what the nature and diversity of these pathogens truly represent [25,26]. As such, the time has come to redefine the environmental coverage by these organisms, beyond a clinical setting.…”

“…But in recent times, it is now very clear that such nosocomial pathogens could be isolated from other ecosystems[3,4,38]. Fernando et al[26] showed evidence of the occurrence of Acinetobacter baumannii in the surface water resources collected from the South Nation River (SNR) drainage basin in Eastern Ontario, Canada, in 2013. Goswami et al[29] also isolated A. baumannii from the river in West Bengal, India.…”