Antimicrobial Resistance Determinants in Genomes and Plasmids from Acinetobacter baumannii Clinical Isolates.

Itziar Chapartegui-González,José Ramos-Vivas,Jesús Navas,María Lázaro-Díez,Santiago Redondo-Salvo

doi:10.3390/antibiotics10070753

Abstract

Acinetobacter baumannii is a Gram-negative coccoid rod species, clinically relevant as a human pathogen, included in the ESKAPE group. Carbapenem-resistant A. baumannii (CRAB) are considered by the World Health Organization (WHO) as a critical priority pathogen for the research and development of new antibiotics. Some of the most relevant features of this pathogen are its intrinsic multidrug resistance and its ability to acquire rapid and effective new resistant determinants against last-resort clinical antibiotics, mostly from other ESKAPE species. The presence of plasmids and mobile genetic elements in their genomes contributes to the acquisition of new antimicrobial resistance determinants. However, although A. baumannii has arisen as an important human pathogen, information about these elements is still not well understood. Current genomic analysis availability has increased our ability to understand the microevolution of bacterial pathogens, including point mutations, genetic dissemination, genomic stability, and pan- and core-genome compositions. In this work, we deeply studied the genomes of four clinical strains from our hospital, and the reference strain ATCC®19606TM, which have shown a remarkable ability to survive and maintain their effective capacity when subjected to long-term stress conditions. With that, our aim was presenting a detailed analysis of their genomes, including antibiotic resistance determinants and plasmid composition.

Highlights

The discovery of penicillin in 1928 marked the beginning of the antibiotic era, which meant a revolution in public health
Despite the fact that multidrug-resistant bacteria pose a threat to both global morbidity and mortality, pharmaceutics research and development has not been able to meet the clinical need for new antibiotics
Acinetobacter spp. are Gram-negative coccoid rods, mostly of an environmental origin, but with some species being clinically relevant as human pathogens, especially A. baumannii, a human pathogenic one included in the ESKAPE group [3]

Summary

Introduction

The discovery of penicillin in 1928 marked the beginning of the antibiotic era, which meant a revolution in public health. Their wrong utilization in the last decades has significantly increased the number of antimicrobial-resistant strains [1]. The World Health Organization (WHO) has created “a priority list of antibiotic-resistant bacteria”, in which the Acinetobacter genus is included [2]. Carbapenemresistant A. baumannii (CRAB) strains are considered by the WHO as critical priority pathogens for the research and development of new antibiotics due to their limiting therapeutic options [2]. As a human opportunistic pathogen, it is usually associated with the most critical patients in Intensive Care Units (ICUs) in whom they could cause bacteremia, pneumonia, and different wound infections, among other things [6,7]

Objectives

Methods

Results