scholarly journals 7X multiplexed, optofluidic detection of nucleic acids for antibiotic-resistance bacterial screening

2020 ◽  
Vol 28 (22) ◽  
pp. 33019
Author(s):  
G. G. Meena ◽  
T. A. Wall ◽  
M. A. Stott ◽  
O. Brown ◽  
R. Robison ◽  
...  
Keyword(s):  
Antibiotic Resistance ◽  
Nucleic Acids ◽  
Bacterial Screening

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
Keyword(s):  
Antibiotic Resistance ◽  
Nucleic Acids ◽  
Antisense Oligonucleotides ◽  
Bacterial Infections ◽  
Genetic Disorders ◽  
Antibiotic Resistance Genes ◽  
Short Review ◽  
Rnase H ◽  
Biological Processes ◽  
Locked Nucleic Acids

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.

Drug Resistance and Gene Transfer Mechanisms in Respiratory/Oral Bacteria

2018 ◽  
Vol 97 (10) ◽  
pp. 1092-1099 ◽  
Author(s):  
S. Jiang ◽  
J. Zeng ◽  
X. Zhou ◽  
Y. Li
Keyword(s):  
Antibiotic Resistance ◽  
Gene Transfer ◽  
Nucleic Acids ◽  
Bacterial Resistance ◽  
Defense Mechanism ◽  
Oral Bacteria ◽  
New Drugs ◽  
Resistant Bacteria ◽  
Oral Microbiota ◽  
Innate Defense

Growing evidence suggests the existence of new antibiotic resistance mechanisms. Recent studies have revealed that quorum-quenching enzymes, such as MacQ, are involved in both antibiotic resistance and cell-cell communication. Furthermore, some small bacterial regulatory RNAs, classified into RNA attenuators and small RNAs, modulate the expression of resistance genes. For example, small RNA sprX, can shape bacterial resistance to glycopeptide antibiotics via specific downregulation of protein SpoVG. Moreover, some bacterial lipocalins capture antibiotics in the extracellular space, contributing to severe multidrug resistance. But this defense mechanism may be influenced by Agr-regulated toxins and liposoluble vitamins. Outer membrane porin proteins and efflux pumps can influence intracellular concentrations of antibiotics. Alterations in target enzymes or antibiotics prevent binding to targets, which act to confer high levels of resistance in respiratory/oral bacteria. As described recently, horizontal gene transfer, including conjugation, transduction and transformation, is common in respiratory/oral microflora. Many conjugative transposons and plasmids discovered to date encode antibiotic resistance proteins and can be transferred from donor bacteria to transient recipient bacteria. New classes of mobile genetic elements are also being identified. For example, nucleic acids that circulate in the bloodstream (circulating nucleic acids) can integrate into the host cell genome by up-regulation of DNA damage and repair pathways. With multidrug resistant bacteria on the rise, new drugs have been developed to combate bacterial antibiotic resistance, such as innate defense regulators, reactive oxygen species and microbial volatile compounds. This review summaries various aspects and mechanisms of antibiotic resistance in the respiratory/oral microbiota. A better understanding of these mechanisms will facilitate minimization of the emergence of antibiotic resistance.

A Method for Processing Digital Images of Colorimetric Biochipes for Quantitative Determination for Bacterial Antibiotic Resistance

2021 ◽  
Vol 37 (5) ◽  
pp. 123-131
Author(s):  
G.V. Presnova ◽  
V.G. Grigorenko ◽  
M.M. Ulyashova ◽  
М.Yu. Rubtsova
Keyword(s):  
Antibiotic Resistance ◽  
Nucleic Acids ◽  
Quantitative Determination ◽  
Resistance Genes ◽  
Molecular Genetic ◽  
Antibiotic Resistance Genes ◽  
Molecular Genetic Analysis ◽  
Beta Lactamases ◽  
The Government

Abstract-Molecular genetic analysis methods based on the technology of colorimetric biochip have shown their effectiveness in identifying antibiotic resistance genes in bacteria. For the quantitative determination of nucleic acids, a comparative study of methods for converting digital color images of biochips into monochrome black-and-white versions using RGB and CMYK color models has been carried out. A 19-mer single-stranded oligonucleotide and two model mRNAs corresponding to the genes of two types of clinically relevant beta-lactamases (CTX-M and NDM) were studied as objects. The widest range of staining intensity and the best analytical characteristics for the determination of all types of studied nucleic acids were obtained using the red channel of the RGB color model. The detection limits were 0.10 ± 0.02 pmol/μl for the 19-mer oligonucleotide, and 3.0 ± 0.2 amol/μl and 8.0 ± 0.6 amol/μl for mRNA of beta-lactamases CTX-M-116 and NDM-1, respectively. The developed method can be used for the quantitative determination of expressing antibiotic resistance genes in bacteria with multiple resistance to antimicrobial drugs. Key words: colorimetric biochips, hybridization analysis, DNA, mRNA, antibiotic resistance, beta-lactamases The work was supported by the Government Program of the Lomonosov Moscow State University (АААА-А21-121011290089-4).

scholarly journals Silencing Antibiotic Resistance with Antisense Oligonucleotides

2021 ◽  
Author(s):  
Saumya Jani ◽  
Maria Soledad Ramirez ◽  
Marcelo Tolmasky
Keyword(s):  
Antibiotic Resistance ◽  
Nucleic Acids ◽  
Antisense Oligonucleotides ◽  
Bacterial Infections ◽  
Genetic Disorders ◽  
Antibiotic Resistance Genes ◽  
Rnase H ◽  
Biological Processes ◽  
Beta Lactams ◽  
Locked Nucleic Acids

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.

Antisense agents against antibiotic-resistant bacteria

2022 ◽  
Vol 23 ◽  
Author(s):  
Javad Nezhadi ◽  
Sepehr Taghizadeh ◽  
Ehsaneh Khodadadi ◽  
Mehdi Yousefi ◽  
Khudaverdi Ganbarov ◽  
...  
Keyword(s):  
Antibiotic Resistance ◽  
Nucleic Acids ◽  
Bacterial Species ◽  
Antibacterial Properties ◽  
Resistant Bacteria ◽  
Antibiotic Resistant Bacteria ◽  
Antibiotic Resistant ◽  
Pharmacokinetic Properties ◽  
A New Technique ◽  
New Perspective

Abstract: The dramatically increasing levels of antibiotic resistance are being seen worldwide, and is a significant threat to public health. Antibiotic and drug resistance is seen in various bacterial species. Antibiotic resistance is associated with increased morbidity and mortality and increased treatment costs. Antisense-relevant technologies include the utilization of oligonucleotide molecules to interfere with gene expression, as a new technique for the treatment of antibiotic-resistant bacteria has been proposed antisense agents or nucleic acids analogs with antibacterial properties, which are commonly very short and their size almost 10-20 bases and can be hinted to peptide nucleic acids (PNAs), phosphorodiamidate morpholino oligomers (PPMOs) and locked nucleic acids (LNAs). This review highlights that PNAs, PPMOs, and LNAs target the genes that cause destroy the gene and inhibit the growth of bacteria. These results open a new perspective for therapeutic intervention. In future studies, it is necessary to examine different aspects of antisense agents, for example, safety, toxicity, and pharmacokinetic properties of antisense agents to be employed in clinical treatment.

Electron Microscopy of Nucleic Acids

1974 ◽  
Vol 32 ◽  
pp. 302-303
Author(s):  
Norman Davidson
Keyword(s):  
Electron Microscopy ◽  
Nucleic Acids ◽  
Basic Protein ◽  
Molecular Biologist ◽  
Topological Properties ◽  
Protein Film ◽  
Polynucleotide Chain

The basic protein film technique for mounting nucleic acids for electron microscopy has proven to be a general and powerful tool for the working molecular biologist in characterizing different nucleic acids. It i s possible to measure molecular lengths of duplex and single-stranded DNAs and RNAs. In particular, it is thus possible to as certain whether or not the nucleic acids extracted from a particular source are or are not homogeneous in length. The topological properties of the polynucleotide chain (linear or circular, relaxed or supercoiled circles, interlocked circles, etc. ) can also be as certained.

mRNA localization by Electron microscopic in situ hybridization

1991 ◽  
Vol 49 ◽  
pp. 430-431
Author(s):  
J. A. Pollock ◽  
M. Martone ◽  
T. Deerinck ◽  
M. H. Ellisman
Keyword(s):  
Electron Microscopy ◽  
High Resolution ◽  
Nucleic Acids ◽  
Recombinant Dna ◽  
Light And Electron Microscopy ◽  
Electron Microscopic ◽  
High Voltage Electron Microscopy ◽  
Functional Sites ◽  
Voltage Electron

Localization of specific proteins in cells by both light and electron microscopy has been facilitate by the availability of antibodies that recognize unique features of these proteins. High resolution localization studies conducted over the last 25 years have allowed biologists to study the synthesis, translocation and ultimate functional sites for many important classes of proteins. Recently, recombinant DNA techniques in molecular biology have allowed the production of specific probes for localization of nucleic acids by “in situ” hybridization. The availability of these probes potentially opens a new set of questions to experimental investigation regarding the subcellular distribution of specific DNA's and RNA's. Nucleic acids have a much lower “copy number” per cell than a typical protein, ranging from one copy to perhaps several thousand. Therefore, sensitive, high resolution techniques are required. There are several reasons why Intermediate Voltage Electron Microscopy (IVEM) and High Voltage Electron Microscopy (HVEM) are most useful for localization of nucleic acids in situ.

Nucleic Acid Molecules Prepared by Monolayer Techniques

1972 ◽  
Vol 30 ◽  
pp. 178-179
Author(s):  
Dimitrij Lang
Keyword(s):  
Electron Microscopy ◽  
Standard Deviation ◽  
Nucleic Acid ◽  
Cytochrome C ◽  
Nucleic Acids ◽  
Contour Length ◽  
Sample Standard Deviation ◽  
Molecular Weights ◽  
Length Measurements ◽  
Protein Monolayer

The success of the protein monolayer technique for electron microscopy of individual DNA molecules is based on the prevention of aggregation and orientation of the molecules during drying on specimen grids. DNA adsorbs first to a surface-denatured, insoluble cytochrome c monolayer which is then transferred to grids, without major distortion, by touching. Fig. 1 shows three basic procedures which, modified or not, permit the study of various important properties of nucleic acids, either in concert with other methods or exclusively:1) Molecular weights relative to DNA standards as well as number distributions of molecular weights can be obtained from contour length measurements with a sample standard deviation between 1 and 4%.

Sign in / Sign up

Export Citation Format

Share Document