Robust performance of a membrane bioreactor for removing antibiotic resistance genes exposed to antibiotics: Role of membrane foulants

AbstractIt is generally accepted that intervention strategies to curb antibiotic resistance cannot solely focus on human and veterinary medicine but must also consider environmental settings. While the environment clearly has a role in the transmission of resistant bacteria, it is less clear what role it plays in the emergence of novel types of resistance. It has been suggested that the environment constitutes an enormous recruitment ground for resistance genes to pathogens, but the extent to which this actually happens is unknown. In this study, we built a model framework for resistance emergence and used the available quantitative data on the relevant processes to identify the steps which are limiting the appearance of antibiotic resistance determinants in human or animal pathogens. We also assessed the effect of uncertainty in the available data on the model results. We found that in a majority of scenarios, the environment would only play a minor role in the emergence of novel resistance genes. However, the uncertainty around this role is enormous, highlighting an urgent need of more quantitative data to understand the role of the environment in antibiotic resistance development. Specifically, more data is most needed on the fitness costs of antibiotic resistance gene (ARG) carriage, the degree of dispersal of resistant bacteria from the environment to humans, but also the rates of mobilization and horizontal transfer of ARGs. Quantitative data on these processes is instrumental to determine which processes that should be targeted for interventions to curb development and transmission of resistance.

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Effect of frameshift mutagen acriflavine on control of resistance genes in Acinetobacter baumannii

Journal of Medical Microbiology ◽

10.1099/jmm.0.025544-0 ◽

2011 ◽

Vol 60 (2) ◽

pp. 211-215 ◽

Cited By ~ 8

Author(s):

B. S. Lopes ◽

A. Hamouda ◽

J. Findlay ◽

S. G. B. Amyes

Keyword(s):

Gene Expression ◽

Antibiotic Resistance ◽

Acinetobacter Baumannii ◽

Resistance Genes ◽

Outer Membrane Proteins ◽

Antibiotic Resistance Gene ◽

Antibiotic Resistance Genes ◽

Multidrug Resistant ◽

The Body

Acinetobacter baumannii is a Gram-negative pathogenic bacterium that often exhibits a multidrug-resistant phenotype causing infections at various sites of the body and increasingly leading to septicaemic shock. This study evaluated the role of acriflavine, a frameshift mutagen, on the movement of insertion sequence ISAba1 in clinical isolates of A. baumannii, with the focus on changes in expression levels of the bla ADC and bla OXA-51-like genes. Resistance profiles were assessed with consideration of ISAba1 acting as a promoter upstream of the bla ADC or bla OXA-51-like gene. ISAba1 movement was observed in the acriflavine mutants Ab153M and Ab1225M. Ab153M exhibited an increase in the MIC values of carbapenems and ceftazidime, with ISAba1 gained upstream of the bla ADC and bla OXA-51-like genes, correlating with an increase in gene expression. Reduced expression of the 17, 23 and 25 kDa outer-membrane proteins (OMPs) was also observed in Ab153M. There was a significant decrease in MIC values of carbapenems with the loss of ISAba1 upstream of the bla ADC and bla OXA-51-like genes in strain Ab1225M, and a significant decrease in bla OXA-51-like gene expression and, to a lesser extent, in bla ADC expression. Ab1225M and a serially subcultured Ab1225 strain (Ab1225s) exhibited overexpression of the 17, 23, 25 and 27 kDa OMPs. There was a decrease in MIC values of the carbapenems and piperacillin/tazobactam but not of ceftazidime in Ab1225s, which had ISAba1 upstream of the bla ADC and bla OXA-51-like genes. A significant decrease in bla OXA-51-like expression was observed in Ab1225s, whereas the expression of bla ADC was similar to that in the Ab1225 parental strain. The attenuation in this strain may be due to overexpression of OMPs and it is clear that, even if ISAba1 is present upstream of an antibiotic resistance gene, it may not necessarily contribute towards the overexpression of antibiotic resistance genes (bla OXA-51-like in Ab1225s). Movement of the IS element within the A. baumannii chromosome may be an important regulatory mechanism employed by the bacterium under particular stress conditions, and the ability to upregulate the expression of antibiotic resistance genes is likely to be an important factor in the pathogenicity of this bacterium.

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Removal of antibiotic residues, antibiotic resistant bacteria and antibiotic resistance genes in municipal wastewater by membrane bioreactor systems

Water Research ◽

10.1016/j.watres.2018.08.060 ◽

2018 ◽

Vol 145 ◽

pp. 498-508 ◽

Cited By ~ 78

Author(s):

Thai-Hoang Le ◽

Charmaine Ng ◽

Ngoc Han Tran ◽

Hongjie Chen ◽

Karina Yew-Hoong Gin

Keyword(s):

Antibiotic Resistance ◽

Resistance Genes ◽

Membrane Bioreactor ◽

Municipal Wastewater ◽

Antibiotic Resistance Genes ◽

Resistant Bacteria ◽

Antibiotic Residues ◽

Antibiotic Resistant Bacteria ◽

Antibiotic Resistant

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Deciphering the role of calcium peroxide on the fate of antibiotic resistance genes and mobile genetic elements during bioelectrochemically-assisted anaerobic composting of excess dewatered sludge

Chemical Engineering Journal ◽

10.1016/j.cej.2020.125355 ◽

2020 ◽

Vol 397 ◽

pp. 125355 ◽

Cited By ~ 2

Author(s):

Hang Yu ◽

Qingliang Zhao ◽

Fanchao Meng ◽

Lingyu Ruan ◽

Tiantian Sun ◽

...

Keyword(s):

Antibiotic Resistance ◽

Resistance Genes ◽

Antibiotic Resistance Genes ◽

Mobile Genetic Elements ◽

Calcium Peroxide ◽

Genetic Elements ◽

Dewatered Sludge

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Tn1403, a Multiple-Antibiotic Resistance Transposon Made Up of Three Distinct Transposons

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.01279-06 ◽

2007 ◽

Vol 51 (5) ◽

pp. 1827-1829 ◽

Cited By ~ 31

Author(s):

H. W. Stokes ◽

Liam D. H. Elbourne ◽

Ruth M. Hall

Keyword(s):

Antibiotic Resistance ◽

Resistance Genes ◽

Antibiotic Resistance Genes ◽

Tetracycline Resistance ◽

Resistance Determinant ◽

Multiple Antibiotic Resistance

ABSTRACT Transposon Tn1403 from a clinical Pseudomonas strain is composed of three transposons, including Tn5393c. A related transposon Tn1404* from a plant-associated Pseudomonas strain lacks Tn5393 but includes a transposon carrying the tet(C) tetracycline resistance determinant. These compound transposons illustrate the role of preexisting transposons in generating clusters of antibiotic resistance genes.

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