Project description:We compared the exposure of E. coli MG1655 to ten commonly used antiseptics and disinfectants for short (30min) and long (7-12h) term, looking for common and unique stress response elements.
Project description:The goals of this study are to use SWATH-MS to detect bacterial proteomic profiles of wild-type Acinetobacter baylyi ADP1, and its protein response under the exposure of disinfectants, including chloramine and free chlorine. The concentrations of disinfectants were 10 mg/L. The group without dosing disinfectant was the control group. Each concentration was conducted in triplicate. By comparing the proteomic profiles of experimental groups and control group, the effects of disinfectants on translational levels can be revealed.
Project description:Disinfection is very critical for the removal of pathogens that constitute public health concerns. However, a rounded understanding of the antimicrobial action of different classes of disinfectants is still lacking. In this work, the physiological and transcriptomic responses of Escherichia coli to two different disinfectants namely: potassium ferrate (K2FeO4) and more conventional disinfectant, sodium hypochlorite (NaOCl), were examined. The study aimed to examine E. coli genetic response to ferrate and compare and contrast it to the genetic response of E. coli to hypochlorite.
Project description:The goals of this study are to use Next-generation sequencing (NGS) to detect bacterial mRNA profiles of wild-type A.baylyi ADP1, and its mRNA response under the exposure of two disinfectants, chloramine and free chlorine. The concentrations 10 mg/L. The group without dosing disinfectants was the control group. Each concentration was conducted in triplicate. By comparing the mRNA profiles of experimental groups and control group, the effects of these two disinfectants on transcriptional levels can be revealed. Illumina HiSeq 2500 was applied. The NGS QC toolkit (version 2.3.3) was used to treat the raw sequence reads to trim the 3’-end residual adaptors and primers, and the ambiguous characters in the reads were removed. Then, the sequence reads consisting of at least 85% bases were progressively trimmed at the 3’-ends until a quality value ≥ 20 were kept. Downstream analyses were performed using the generated clean reads of no shorter than 75 bp. The clean reads of each sample were aligned to the A.baylyi ADP1 reference genome (NC_005966.1), using SeqAlto (version 0.5). Cufflinks (version 2.2.1) to calculate the strand-specific coverage for each gene, and to analyze the differential expression in triplicate bacterial cell cultures. The statistical analyses and visualization were conducted using CummeRbund package in R. (http://compbio.mit.edu/cummeRbund/). Gene expression was calculated as fragments per kilobase of a gene per million mapped reads (FPKM, a normalized value generated from the frequency of detection and the length of a given gene.
Project description:Biofilms in dental unit waterlines (DUWL) are a potentially significant source of contamination posing a significant health risk as these may come into contact with patients and dental staff during treatment. The aim of this study was to evaluate the microbiological quality of DUWL water treated by Biofilm-Removing-System® (BRS®) and Alpron®/Bilpron® disinfectant solutions for six years in a French university hospital. The microbiological quality of water supplied by 68 dental units-initially shock treated with BRS®, then continuously treated by Alpron® with sterile water during working days and Bilpron® during inactivity period, and combined with purging every morning and after each patient-was assessed biannually during six years for total culturable aerobic bacteria at 22 °C and 36 °C, Legionella sp., Pseudomonas aeruginosa, and total coliforms. A total of 628 samples were analyzed, 99.8% were compliant with extended microbiological levels, and we never detected pathogen bacteria like Legionella sp. and P. aeruginosa. Only one sample (0.2%) was noncompliant with the level of total culturable aerobic bacteria at 36 °C, which exceeded 140 colony forming units per mL. The protocol implemented in our university hospital gives excellent results and enables control of the microbiological quality of DUWL water in the long term.