scholarly journals Silencing Antibiotic Resistance with Antisense Oligonucleotides

Biomedicines ◽  
2021 ◽  
Vol 9 (4) ◽  
pp. 416
Author(s):  
Saumya Jani ◽  
Maria Soledad Ramirez ◽  
Marcelo E. Tolmasky

Antisense technologies consist of the utilization of oligonucleotides or oligonucleotide analogs to interfere with undesirable biological processes, commonly through inhibition of expression of selected genes. This field holds a lot of promise for the treatment of a very diverse group of diseases including viral and bacterial infections, genetic disorders, and cancer. To date, drugs approved for utilization in clinics or in clinical trials target diseases other than bacterial infections. Although several groups and companies are working on different strategies, the application of antisense technologies to prokaryotes still lags with respect to those that target other human diseases. In those cases where the focus is on bacterial pathogens, a subset of the research is dedicated to produce antisense compounds that silence or reduce expression of antibiotic resistance genes. Therefore, these compounds will be adjuvants administered with the antibiotic to which they reduce resistance levels. A varied group of oligonucleotide analogs like phosphorothioate or phosphorodiamidate morpholino residues, as well as peptide nucleic acids, locked nucleic acids and bridge nucleic acids, the latter two in gapmer configuration, have been utilized to reduce resistance levels. The major mechanisms of inhibition include eliciting cleavage of the target mRNA by the host’s RNase H or RNase P, and steric hindrance. The different approaches targeting resistance to β-lactams include carbapenems, aminoglycosides, chloramphenicol, macrolides, and fluoroquinolones. The purpose of this short review is to summarize the attempts to develop antisense compounds that inhibit expression of resistance to antibiotics.

Author(s):  
Saumya Jani ◽  
Maria Soledad Ramirez ◽  
Marcelo Tolmasky

Antisense technologies consist of the utilization of oligonucleotides or oligonucleotide analogs to interfere with undesirable biological processes, commonly through inhibition of expression of selected genes. This field holds a lot of promise for the treatment of a very diverse group of diseases including viral and bacterial infections, genetic disorders, and cancer. To date, drugs approved for utilization in clinics or in clinical trials target diseases other than bacterial infections. Although several groups and companies are working on different strategies, the application of antisense technologies to prokaryotes still lags with respect to those that target other human diseases. In those cases where the focus is on bacterial pathogens, a subset of the research is dedicated to produce antisense compounds that silence or reduce expression of antibiotic resistance genes. Therefore, these compounds will be adjuvants administered with the antibiotic to which they reduce resistance levels. A varied group of oligonucleotide analogs like phosphorothioate or phosphorodiamidate morpholino residues, as well as peptide nucleic acids, locked nucleic acids and bridge nucleic acids, the latter two in gapmer configuration, have been utilized to reduce resistance levels. The major mechanisms of inhibition include eliciting cleavage of the target mRNA by the host’s RNase H or RNase P, and steric hindrance. The different approaches targeted resistance to β-lactams including carbapenems, aminoglycosides, chloramphenicol, macrolides, and fluoroquinolones.


Antibiotics ◽  
2020 ◽  
Vol 9 (10) ◽  
pp. 688
Author(s):  
Shashi B. Kumar ◽  
Shanvanth R. Arnipalli ◽  
Ouliana Ziouzenkova

Antibiotics have been used as essential therapeutics for nearly 100 years and, increasingly, as a preventive agent in the agricultural and animal industry. Continuous use and misuse of antibiotics have provoked the development of antibiotic resistant bacteria that progressively increased mortality from multidrug-resistant bacterial infections, thereby posing a tremendous threat to public health. The goal of our review is to advance the understanding of mechanisms of dissemination and the development of antibiotic resistance genes in the context of nutrition and related clinical, agricultural, veterinary, and environmental settings. We conclude with an overview of alternative strategies, including probiotics, essential oils, vaccines, and antibodies, as primary or adjunct preventive antimicrobial measures or therapies against multidrug-resistant bacterial infections. The solution for antibiotic resistance will require comprehensive and incessant efforts of policymakers in agriculture along with the development of alternative therapeutics by experts in diverse fields of microbiology, biochemistry, clinical research, genetic, and computational engineering.


2000 ◽  
Vol 97 (10) ◽  
pp. 5633-5638 ◽  
Author(s):  
C. Wahlestedt ◽  
P. Salmi ◽  
L. Good ◽  
J. Kela ◽  
T. Johnsson ◽  
...  

2019 ◽  
Author(s):  
Marinelle Rodrigues ◽  
Sara W. McBride ◽  
Karthik Hullahalli ◽  
Kelli L. Palmer ◽  
Breck A. Duerkop

AbstractThe innovation of new therapies to combat multidrug-resistant (MDR) bacteria is being outpaced by the continued rise of MDR bacterial infections. Of particular concern are hospital-acquired infections (HAIs) recalcitrant to antibiotic therapies. The Gram-positive intestinal pathobiontEnterococcus faecalisis associated with HAIs and some strains are MDR. Therefore, novel strategies to controlE. faecalispopulations are needed. We previously characterized anE. faecalisType II CRISPR-Cas system and demonstrated its utility in the sequence-specific removal of antibiotic resistance determinants. Here we present work describing the adaption of this CRISPR-Cas system into a constitutively expressed module encoded on a pheromone-responsive conjugative plasmid that efficiently transfers toE. faecalisfor the selective removal of antibiotic resistance genes. Usingin vitrocompetition assays, we show that these CRISPR-Cas-encoding delivery plasmids, or CRISPR-Cas antimicrobials, can reduce the occurrence of antibiotic resistance in enterococcal populations in a sequence-specific manner. Furthermore, we demonstrate that deployment of CRISPR-Cas antimicrobials in the murine intestine reduces the occurrence of antibiotic-resistantE. faecalisby several orders of magnitude. Finally, we show thatE. faecalisdonor strains harboring CRISPR-Cas antimicrobials are immune to uptake of antibiotic resistance determinantsin vivo. Our results demonstrate that conjugative delivery of CRISPR-Cas antimicrobials may be adaptable for future deployment from probiotic bacteria for exact targeting of defined MDR bacteria or for precision engineering of polymicrobial communities in the mammalian intestine.ImportanceCRISPR-Cas nucleic acid targeting systems hold promise for the amelioration of multidrug-resistant enterococci, yet the utility of such tools in the context of the intestinal environment where enterococci reside is understudied. We describe the development of a CRISPR-Cas antimicrobial, deployed on a conjugative plasmid, for the targeted removal of antibiotic resistance genes from intestinalEnterococcus faecalis. We demonstrate that CRISPR-Cas targeting reduces antibiotic resistance ofE. faecalisby several orders of magnitude in the intestine. Although barriers exist that influence the penetrance of the conjugative CRISPR-Cas antimicrobial among target recipientE. faecaliscells, the removal of antibiotic resistance genes inE. faecalisupon uptake of the CRISPR-Cas antimicrobial is absolute. In addition, cells that obtain the CRISPR-Cas antimicrobial are immunized against the acquisition of new antibiotic resistance genes. This study suggests a potential path toward plasmid based CRISPR-Cas therapies in the intestine.


2021 ◽  
Author(s):  
bahman Ghadami Petroudi ◽  
Rahman Shokri ◽  
Davoud Esmaeili

Abstract Bckground: Increasing use of beta-lactam antimicrobials in the treatment of bacterial infections has increased resistance against them. Objectives: This study aimed to investigate the patterns of antibiotic susceptibility to beta-lactam antibiotics and to investigate the presence of beta-lactamase and Metallo-beta-lactamase genes blaKPC, blaTEM, blaAmpc, blaIND, blaSIM, and blaGIM in clinical specimens of Escherichia coli.Methods: In this study, 100 urine samples were collected from different wards of hospitals and treatment centers in the west of Tehran province, and 100 strains of Escherichia coli were confirmed by biochemical tests. In the next step, a susceptibility test was performed on 3 selected antibiotics. Then, using the Combine Disk Test method, ESBL and MBL strains were identified. Finally, using the multiplex PCR method, the strains producing KPC, TEM, Ampc, IND, GIM, and SIM enzymes were identified.Results: In this study, the highest resistance of strains to cefotaxime was observed. n = 52 (52%) and their highest sensitivity to imipenem was seen n = 95 (95%). Also, n = 53 (53%) of the samples had ESBL genes. Also, 41 isolates (77%) of the studied strains contained the blaTEM gene, 12 isolates (23%) of the strains contained the blaAmpc gene and 20 isolates (38%) of the strains contained blakpc gene. Also, n= 19 (19%) of the samples had MBL genes. Also, 4 isolates (21%) of the strains contained the IND gene, 4 isolates (21%) of the strains contained the GIM gene, 7 isolates (37%) contained the SIM gene.Conclusion: Due to the high percentage of resistance to third-generation cephalosporins, careful antibiogram testing before antibiotic administration in infections caused by ESBL and MBL-producing organisms is an unavoidable necessity. Therefore, by quickly and correctly identifying the pattern of antibiotic resistance, the physician will be able to select the appropriate antibiotic therapy and prevent the spread of antibiotic resistance.


2021 ◽  
Vol 9 (2) ◽  
pp. 280
Author(s):  
Reetta Penttinen ◽  
Cindy Given ◽  
Matti Jalasvuori

Antibiotic resistance genes of important Gram-negative bacterial pathogens are residing in mobile genetic elements such as conjugative plasmids. These elements rapidly disperse between cells when antibiotics are present and hence our continuous use of antimicrobials selects for elements that often harbor multiple resistance genes. Plasmid-dependent (or male-specific or, in some cases, pilus-dependent) bacteriophages are bacterial viruses that infect specifically bacteria that carry certain plasmids. The introduction of these specialized phages into a plasmid-abundant bacterial community has many beneficial effects from an anthropocentric viewpoint: the majority of the plasmids are lost while the remaining plasmids acquire mutations that make them untransferable between pathogens. Recently, bacteriophage-based therapies have become a more acceptable choice to treat multi-resistant bacterial infections. Accordingly, there is a possibility to utilize these specialized phages, which are not dependent on any particular pathogenic species or strain but rather on the resistance-providing elements, in order to improve or enlengthen the lifespan of conventional antibiotic approaches. Here, we take a snapshot of the current knowledge of plasmid-dependent bacteriophages.


2019 ◽  
Vol 63 (11) ◽  
Author(s):  
Marinelle Rodrigues ◽  
Sara W. McBride ◽  
Karthik Hullahalli ◽  
Kelli L. Palmer ◽  
Breck A. Duerkop

ABSTRACT The innovation of new therapies to combat multidrug-resistant (MDR) bacteria is being outpaced by the continued rise of MDR bacterial infections. Of particular concern are hospital-acquired infections (HAIs) that are recalcitrant to antibiotic therapies. The Gram-positive intestinal pathobiont Enterococcus faecalis is associated with HAIs, and some strains are MDR. Therefore, novel strategies to control E. faecalis populations are needed. We previously characterized an E. faecalis type II CRISPR-Cas system and demonstrated its utility in the sequence-specific removal of antibiotic resistance determinants. Here, we present work describing the adaption of this CRISPR-Cas system into a constitutively expressed module encoded on a pheromone-responsive conjugative plasmid that efficiently transfers to E. faecalis for the selective removal of antibiotic resistance genes. Using in vitro competition assays, we show that these CRISPR-Cas-encoding delivery plasmids, or CRISPR-Cas antimicrobials, can reduce the occurrence of antibiotic resistance in enterococcal populations in a sequence-specific manner. Furthermore, we demonstrate that deployment of CRISPR-Cas antimicrobials in the murine intestine reduces the occurrence of antibiotic-resistant E. faecalis by several orders of magnitude. Finally, we show that E. faecalis donor strains harboring CRISPR-Cas antimicrobials are immune to uptake of antibiotic resistance determinants in vivo. Our results demonstrate that conjugative delivery of CRISPR-Cas antimicrobials may be adaptable for future deployment from probiotic bacteria for exact targeting of defined MDR bacteria or for precision engineering of polymicrobial communities in the mammalian intestine.


2021 ◽  
Author(s):  
Bahman Ghadami Petroudi ◽  
Rahman Shokri ◽  
Davoud Esmaeili

Abstract Background: Increasing use of beta-lactam antimicrobials in the treatment of bacterial infections has increased resistance against them. Objectives: This study aimed to investigate the patterns of antibiotic susceptibility to beta-lactam antibiotics and to investigate the presence of beta-lactamase and Metallo-beta-lactamase genes blaKPC, blaTEM, blaAmpc, blaIND, blaSIM, and blaGIM in clinical specimens of Escherichia coli.Methods: In this study, 100 urine samples were collected from different wards of hospitals and treatment centers in the west of Tehran province, and 100 strains of Escherichia coli were confirmed by biochemical tests. In the next step, a susceptibility test was performed on 3 selected antibiotics. Then, using the Combine Disk Test method, ESBL and MBL strains were identified. Finally, using the multiplex PCR method, the strains producing KPC, TEM, Ampc, IND, GIM, and SIM enzymes were identified.Results: In this study, the highest resistance of strains to cefotaxime was observed. n = 52 (52%) and their highest sensitivity to imipenem was seen n = 95 (95%). Also, n = 53 (53%) of the samples had ESBL genes. Also, 41 isolates (77%) of the studied strains contained the blaTEM gene, 12 isolates (23%) of the strains contained the blaAmpc gene and 20 isolates (38%) of the strains contained blakpc gene. Also, n= 19 (19%) of the samples had MBL genes. Also, 4 isolates (21%) of the strains contained the IND gene, 4 isolates (21%) of the strains contained the GIM gene, 7 isolates (37%) contained the SIM gene.Conclusion: Due to the high percentage of resistance to third-generation cephalosporins, careful antibiogram testing before antibiotic administration in infections caused by ESBL and MBL-producing organisms is an unavoidable necessity. Therefore, by quickly and correctly identifying the pattern of antibiotic resistance, the physician will be able to select the appropriate antibiotic therapy and prevent the spread of antibiotic resistance.


2016 ◽  
Author(s):  
Eric van der Helm ◽  
Lejla Imamovic ◽  
Mostafa M Hashim Ellabaan ◽  
Willem van Schaik ◽  
Anna Koza ◽  
...  

AbstractThe emergence of antibiotic resistance in human pathogens has become a major threat to modern medicine and in particular hospitalized patients. The outcome of antibiotic treatment can be affected by the composition of the gut resistome either by enabling resistance gene acquisition of infecting pathogens or by modulating the collateral effects of antibiotic treatment on the commensal microbiome. Accordingly, knowledge of the gut resistome composition could enable more effective and individualized treatment of bacterial infections. Yet, rapid workflows for resistome characterization are lacking. To address this challenge we developed the poreFUME workflow that deploys functional metagenomic selections and nanopore sequencing to resistome mapping. We demonstrate the approach by functionally characterizing the gut resistome of an ICU patient. The accuracy of the poreFUME pipeline is >97 % sufficient for the reliable annotation of antibiotic resistance genes. The poreFUME pipeline provides a promising approach for efficient resistome profiling that could inform antibiotic treatment decisions in the future.


Sign in / Sign up

Export Citation Format

Share Document