Factors that enhance the ability of Pseudomonas aeruginosa to resist the action of antibiotics
type: CreativeWork
description: P.aeruginosa is one of the most important pathogens in nosocomial infections and fails to respond to standard treatment, particularly in the case of patients subjected to prolong antibiotic treatment. To generate a more comprehensive understanding of the failure of antimicrobial treatment, focusing especially on the adaptive resistance could be the key area that the bacterium develops in this phenomenon. Most studies on antibiotic resistance in P.aeruginosa have focused upon genotypic studies. This study set out to develop an in vitro model to examine the effect of continual exposure of P.aeruginosa PA01 to the antibiotics studied. Experiments were initially conducted to consider the factors that having a significant influence on antibiotic susceptibility using a novel fluorescence based assay (OxoPlate® system). P.aeruginosa was subjected to the action of tobramycin, amikacin and colistin under various environmental factors. The results of the in vitro analysis showed that, from among the three antibiotics used, amikacin was the antibiotic where resistance was most readily developed. From these results, chemostat studies were designed to examine prolonged exposure of the antibiotic to planktonic cells. Chemostat cultures were exposed to amikacin at sub-inhibitory concentrations using Evans defined synthetic medium at different dilution rates (D) under glucose limitation. Both cultures grown at 0.025h-1 and 0.06h-1 developed the following characteristics i. low-level amikacin resistance, which exhibited an increase in the MIC 4-fold. ii. a clear development of phenotypic resistance and this resistance was not acquired as evidenced by the loss of resistance on culture into fresh medium lacking antibiotic. iii. adaptive resistance to amikacin conferred low-level resistance to other aminoglycosides such as tobramycin and antibiotics with different modes of action such as colistin. Low oxygen availability was seen in the cultures grown at 0.099 h-1 and 0.125 h-1, which …
abstract: P.aeruginosa is one of the most important pathogens in nosocomial infections and fails to respond to standard treatment, particularly in the case of patients subjected to prolong antibiotic treatment. To generate a more comprehensive understanding of the failure of antimicrobial treatment, focusing especially on the adaptive resistance could be the key area that the bacterium develops in this phenomenon. Most studies on antibiotic resistance in P.aeruginosa have focused upon genotypic studies. This study set out to develop an in vitro model to examine the effect of continual exposure of P.aeruginosa PA01 to the antibiotics studied. Experiments were initially conducted to consider the factors that having a significant influence on antibiotic susceptibility using a novel fluorescence based assay (OxoPlate® system). P.aeruginosa was subjected to the action of tobramycin, amikacin and colistin under various environmental factors. The results of the in vitro analysis showed that, from among the three antibiotics used, amikacin was the antibiotic where resistance was most readily developed. From these results, chemostat studies were designed to examine prolonged exposure of the antibiotic to planktonic cells. Chemostat cultures were exposed to amikacin at sub-inhibitory concentrations using Evans defined synthetic medium at different dilution rates (D) under glucose limitation. Both cultures grown at 0.025h-1 and 0.06h-1 developed the following characteristics i. low-level amikacin resistance, which exhibited an increase in the MIC 4-fold. ii. a clear development of phenotypic resistance and this resistance was not acquired as evidenced by the loss of resistance on culture into fresh medium lacking antibiotic. iii. adaptive resistance to amikacin conferred low-level resistance to other aminoglycosides such as tobramycin and antibiotics with different modes of action such as colistin. Low oxygen availability was seen in the cultures grown at 0.099 h-1 and 0.125 h-1, which …
author: Al Matrood, WAA
keywords: QD Chemistry, QH301 Biology, RM Therapeutics. Pharmacology
date published: 2016-11
date modified: 2026-07-24T06:30:03Z
provider: Liverpool Jon Moores University
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: Liverpool John Moores University

PropertyValue
property ID: DOI
value: 10.24377/LJMU.t.00004727