Genetic Alternatives for Experimental Adaptation to Colistin in Three Lineages.

is characterized by a high adaptive potential, developing resistance in response to antimicrobial pressure. We employed a spatiotemporal evolution model to disclose the pathways of adaptation to colistin, a last-resort polymyxin antimicrobial, among three unrelated lineages. The ATCC-27833 reference strain (), an environmental isolate (), and a clinical isolate with multiple drug resistance () were grown over an increasing 5-step colistin concentration gradient from 0 to 400 mg/L.

Analysis of Isolates from Patients with Cystic Fibrosis Revealed Novel Groups of Filamentous Bacteriophages.

is an opportunistic pathogen that can cause infections in humans, especially in hospital patients with compromised host defence mechanisms, including patients with cystic fibrosis. Filamentous bacteriophages represent a group of single-stranded DNA viruses infecting different bacteria, including and other human and animal pathogens; many of them can replicate when integrated into the bacterial chromosome. Filamentous bacteriophages can contribute to the virulence of and influence the course of the disease.

The classification of bacterial survival strategies in the presence of antimicrobials.

The survival of bacteria under antibiotic therapy varies in nature and is based on the bacterial ability to employ a wide range of fundamentally different resistance mechanisms. This great diversity requires a disambiguation of the term 'resistance' and the development of a more precise classification of bacterial survival strategies during contact with antibiotics. The absence of a unified definition for the terms 'resistance', 'tolerance' and 'persistence' further aggravates the imperfections of the current classification system.