Genomic Characterization of Acinetobacter Species

Acinetobacter species comprise a diverse genus of non-fermenting Gram-negative bacteria, notable for their ability to colonise a wide range of environmental and clinical niches. The genomic characterisation of these organisms has elucidated the basis of their remarkable adaptability, pathogenic potential and multidrug resistance. Comparative analyses reveal an open pan-genome, reflecting extensive gene acquisition and loss across strains. Core genome studies have defined evolutionary lineages within the Acinetobacter calcoaceticus–baumannii complex and clarified species boundaries. Mobile genetic elements—including plasmids, integrons and genomic islands—mediate horizontal gene transfer, disseminating antibiotic resistance determinants such as carbapenemases and aminoglycoside-modifying enzymes. Sequence-based phylogenomic approaches have refined the taxonomy of non-baumannii species and identified phylogenetic markers to track outbreak strains. High-resolution whole-genome sequencing has also uncovered genes involved in environmental resilience, such as those encoding efflux pumps, biofilm-forming factors and enzymes for oxidative stress responses. Collectively, these insights inform global surveillance efforts, guide infection control strategies and support the development of novel diagnostics and therapeutics against a genus of growing clinical concern.

Research from Nature Portfolio

Recent work on Acinetobacter colistiniresistens has delivered the first detailed genome of a community-derived strain exhibiting intrinsic resistance to colistin. Whole-genome sequencing revealed a repertoire of resistance and virulence genes, including mutations in lipid A biosynthesis loci likely responsible for high polymyxin minimum inhibitory concentrations. Comparative analyses with public genomes confirmed a high degree of sequence identity, while in vivo assays demonstrated pathogenic potential in an insect model. The study highlights the public health threat posed by intrinsically resistant Acinetobacter species beyond the healthcare setting and underscores the need for genomic surveillance to detect emerging community reservoirs of resistance.

Genomic Characterization of Acinetobacter Species publication trend

The graph below shows the total number of articles in genomic characterization of acinetobacter species across all publications each year (not limited to Nature Index journals).

Technical terms

Pan-genome: The full complement of genes within a bacterial species, including core and accessory genes.

Core genome: Genes conserved across all strains of a species, reflecting essential functions and evolutionary history.

Horizontal gene transfer: Movement of genetic material between organisms by means other than vertical inheritance, often via plasmids or transposons.

Integron: A genetic element capable of capturing and expressing gene cassettes, notably antibiotic resistance determinants.

Phylogenomics: The analysis of evolutionary relationships using whole-genome data to infer species divergence and relatedness.

Efflux pump: Membrane protein complexes that expel toxic compounds, including antibiotics, contributing to multidrug resistance.

References

1. Genomic and phenotypic characterization of Acinetobacter colistiniresistens isolated from the feces of a healthy member of the community. Scientific Reports (2023).
2. Complete genetic characterization of carbapenem-resistant Acinetobacter johnsonii, co-producing NDM-1, OXA-58, and PER-1 in a patient source. Frontiers in Cellular and Infection Microbiology (2023).
3. A comprehensive genomic analysis provides insights on the high environmental adaptability of Acinetobacter strains. Frontiers in Microbiology (2023).
4. Analysis of Acinetobacter P-type type IV secretion system-encoding plasmid diversity uncovers extensive secretion system conservation and diverse antibiotic resistance determinants. Antimicrobial Agents and Chemotherapy (2024).
5. Phylogenomics Reveals Clear Cases of Misclassification and Genus-Wide Phylogenetic Markers for Acinetobacter. Genome Biology and Evolution (2019).