Systematic analyses identify modes of action of ten clinically relevant biocides and antibiotic antagonism in Acinetobacter baumannii.

Concerns exist that widespread use of antiseptic or disinfectant biocides could contribute to the emergence and spread of multidrug-resistant bacteria. To investigate this, we performed transposon-directed insertion-site sequencing (TraDIS) on the multidrug-resistant pathogen, Acinetobacter baumannii, exposed to a panel of ten structurally diverse and clinically relevant biocides. Multiple gene targets encoding cell envelope or cytoplasmic proteins involved in processes including fatty acid biogenesis, multidrug efflux, the tricarboxylic acid cycle, cell respiration and cell division, were identified to have effects on bacterial fitness upon biocide exposure, suggesting that these compounds may have intracellular targets in addition to their known effects on the cell envelope.

AadT, a new weapon in fight against antibiotics.

Genes encoding a novel multidrug efflux pump, AadT, from the Drug:H antiporter 2 family, were discovered in multidrug resistance plasmids. Here, we profiled the antimicrobial resistance potential, and examined the distribution of these genes. homologs were found in many and other Gram-negative species and were typically adjacent to novel variants of ), which encodes a major tripartite efflux pump in .

Evolution of RND efflux pumps in the development of a successful pathogen.

Aims: This study examined the origins and evolution of the AdeABC, AdeFGH and AdeIJK efflux pumps in the Acinetobacter genus, including human and animal pathogens and species from non-clinical environments.

Methods: Comparative genome analyses were performed using the reference sequences for 70 Acinetobacter species to identify putative orthologs of AdeABC, AdeFGH and AdeIJK and their regulators. Sequence similarities and the genomic locations of coding sequences were correlated with phylogeny to infer modes of evolution.

Complete Genome Sequence of sp. Strain 9, Isolated from Contaminated Australian Groundwater.

Here, we report the 7.7-Mbp genome sequence of sp. strain 9, which was isolated from Australian groundwater contaminated with phenols and trichloroethylene.

The Pasifika Veilomani Project: a pilot online training programme for healthcare workers in managing gender-based violence and family violence and sharing experiences.

Objective: Pacific Island Countries (PICs) record high rates of gender-based violence (GBV). COVID-19 has significantly increased the number of GBV cases globally. This research aims to understand educational pathways for PICs' healthcare workers (HCWs) to strengthen GBV clinical practices in the Pasifika Veilomani (sharing the love) project.

The Acinetobacter baumannii disinfectant resistance protein, AmvA, is a spermidine and spermine efflux pump.

Antimicrobial resistance genes, including multidrug efflux pumps, evolved long before the ubiquitous use of antimicrobials in medicine and infection control. Multidrug efflux pumps often transport metabolites, signals and host-derived molecules in addition to antibiotics or biocides. Understanding their ancestral physiological roles could inform the development of strategies to subvert their activity.

The Membrane Composition Defines the Spatial Organization and Function of a Major Acinetobacter baumannii Drug Efflux System.

Acinetobacter baumannii is one of the world's most problematic nosocomial pathogens. The combination of its intrinsic resistance and ability to acquire resistance markers allow this organism to adjust to antibiotic treatment. Despite being the primary barrier against antibiotic stress, our understanding of the A.

Identification of a Novel Ciprofloxacin Tolerance Gene, , Which Contributes to Filamentation in Acinetobacter baumannii.

Fluoroquinolones are one of the most prescribed broad-spectrum antibiotics. However, their effectiveness is being compromised by high rates of resistance in clinically important organisms, including We sought to investigate the transcriptomic and proteomic responses of the clinical strain AB5075-UW upon exposure to subinhibitory concentrations of ciprofloxacin. Our transcriptomics and proteomics analyses found that the most highly expressed genes and proteins were components of the intact prophage The next most highly expressed gene (and its protein product) under ciprofloxacin stress was a hypothetical gene, ABUW_0098, named here the profloxacin olerance () gene.

The Transcriptomic Signature of Tigecycline in .

Tigecycline, a protein translation inhibitor, is a treatment of last resort for infections caused by the opportunistic multidrug resistance human pathogen . However, strains resistant to tigecycline were reported not long after its clinical introduction. Translation inhibitor antibiotics perturb ribosome function and induce the reduction of (p)ppGpp, an alarmone involved in the stringent response that negatively modulates ribosome production.

The Role of Zinc Efflux during Infection.

is a ubiquitous Gram-negative bacterium, that is associated with significant disease in immunocompromised individuals. The success of is partly attributable to its high level of antibiotic resistance. Further, expresses a broad arsenal of putative zinc efflux systems that are likely to aid environmental persistence and host colonization, but detailed insights into how the bacterium deals with toxic concentrations of zinc are lacking.

Short-chain diamines are the physiological substrates of PACE family efflux pumps.

has rapidly emerged as a major cause of gram-negative hospital infections worldwide. encodes for the transport protein AceI, which confers resistance to chlorhexidine, a widely used antiseptic. AceI is also the prototype for the recently discovered proteobacterial antimicrobial compound efflux (PACE) family of transport proteins that confer resistance to a range of antibiotics and antiseptics in many gram-negative bacteria, including pathogens.

Identification of Novel Host Fatty Acid Stress Adaptation Strategies.

Free fatty acids hold important immune-modulatory roles during infection. However, the host's long-chain polyunsaturated fatty acids, not commonly found in the membranes of bacterial pathogens, also have significant broad-spectrum antibacterial potential. Of these, the omega-6 fatty acid arachidonic acid (AA) and the omega-3 fatty acid decosahexaenoic acid (DHA) are highly abundant; hence, we investigated their effects on the multidrug-resistant human pathogen Our analyses reveal that AA and DHA incorporate into the bacterial membrane and impact bacterial fitness and membrane integrity, with DHA having a more pronounced effect.

Pacing across the membrane: the novel PACE family of efflux pumps is widespread in Gram-negative pathogens.

The proteobacterial antimicrobial compound efflux (PACE) family of transport proteins was only recently described. PACE family transport proteins can confer resistance to a range of biocides used as disinfectants and antiseptics, and are encoded by many important Gram-negative human pathogens. However, we are only just beginning to appreciate the range of functions and the mechanism(s) of transport operating in these proteins.