scholarly journals Piperidine-4-carboxamides target DNA gyrase in Mycobacterium abscessus

2021 ◽  
Author(s):  
Dereje Abate Negatu ◽  
Andreas Beuchel ◽  
Abdeldjalil Madani ◽  
Nadine Alvarez ◽  
Chao Chen ◽  
...  
Keyword(s):  
Dna Damage ◽  
Dna Gyrase ◽  
Resistant Mutant ◽  
Multidrug Resistant ◽  
Antimicrobial Activities ◽  
Mycobacterium Abscessus ◽  
Cross Resistance ◽  
Wild Type ◽  
Reporter Strains ◽  
Effective Drugs

New, more effective drugs for the treatment of lung disease caused by non-tuberculous mycobacteria (NTM) are needed. Among NTM opportunistic pathogens, Mycobacterium abscessus is the most difficult to cure and intrinsically multidrug resistant. In a whole-cell screen of a compound collection active against M. tuberculosis, we previously identified the piperidine-4-carboxamide (P4C) MMV688844 (844) as a hit against M. abscessus. Here, we identified a more potent analog of 844 and showed that both the parent and improved analog retain activity against strains representing all three subspecies of the M. abscessus complex. Furthermore, P4Cs showed bactericidal and anti-biofilm activity. Spontaneous resistance against the P4Cs emerged at a frequency of 10−8/CFU and mapped to gyrA and gyrB encoding the subunits of DNA gyrase. Biochemical studies with recombinant M. abscessus DNA gyrase showed that P4Cs inhibit the wild type enzyme but not the P4C resistant mutant. P4C resistant strains showed limited cross-resistance to the fluoroquinolone moxifloxacin, which is in clinical use for the treatment of macrolide resistant M. abscessus disease, and no cross-resistance to the benzimidazole SPR719, a novel DNA gyrase inhibitor in clinical development for the treatment of mycobacterial diseases. Analyses of P4Cs in recA promotor-based DNA damage reporter strains showed induction of recA promoter activity in wild type but not in P4C resistant mutant background. This indicates that P4Cs, similar to fluoroquinolones, cause DNA gyrase-mediated DNA damage. Together, our results show that P4Cs present a novel class of mycobacterial DNA gyrase inhibitors with attractive antimicrobial activities against the M. abscessus complex.

Expression of hamster P-glycoprotein and multidrug resistance in DNA-mediated transformants of mouse LTA cells

1987 ◽  
Vol 7 (2) ◽  
pp. 718-724
Author(s):  
K L Deuchars ◽  
R P Du ◽  
M Naik ◽  
D Evernden-Porelle ◽  
N Kartner ◽  
...  
Keyword(s):  
Multidrug Resistance ◽  
Dna Sequences ◽  
Multidrug Resistant ◽  
Cross Resistance ◽  
Recipient Mouse ◽  
Strongly Correlated ◽  
Wild Type ◽  
Glycoprotein P ◽  
Single Drug ◽  
P Glycoprotein

The overexpression of a plasma membrane glycoprotein, P-glycoprotein, is strongly correlated with the expression of multidrug resistance. This phenotype (frequently observed in cell lines selected for resistance to a single drug) is characterized by cross resistance to many drugs, some of which are used in cancer chemotherapy. In the present study we showed that DNA-mediated transformants of mouse LTA cells with DNA from multidrug-resistant hamster cells acquired the multidrug resistance phenotype, that the transformants contained hamster P-glycoprotein DNA sequences, that these sequences were amplified whereas the recipient mouse P-glycoprotein sequences remained at wild-type levels, and that the overexpressed P-glycoprotein in these cells was of hamster origin. Furthermore, we showed that the hamster P-glycoprotein sequences were transfected independently of a group of genes that were originally coamplified and linked within a 1-megabase-pair region in the donor hamster genome. These data indicate that the high expression of P-glycoprotein is the only alteration required to mediate multidrug resistance.

scholarly journals A Mycobacterium tuberculosis NBTI DNA gyrase inhibitor is active against Mycobacterium abscessus

2021 ◽  
Author(s):  
Uday S. Ganapathy ◽  
Rubén González del Río ◽  
Mónica Cacho-Izquierdo ◽  
Fátima Ortega ◽  
Joël Lelièvre ◽  
...  
Keyword(s):  
Mycobacterium Tuberculosis ◽  
Low Frequency ◽  
Dna Gyrase ◽  
Resistant Mutant ◽  
Mycobacterium Abscessus ◽  
Mutant Selection ◽  
Intrinsic Drug Resistance ◽  
Lung Infections ◽  
Gyrase Inhibitors

Fluoroquinolones – the only clinically used DNA gyrase inhibitors – are effective against tuberculosis (TB) but are in limited clinical use for non-tuberculous mycobacteria (NTM) lung infections due to intrinsic drug resistance. We sought to test alternative DNA gyrase inhibitors for anti-NTM activity. Mycobacterium tuberculosis Gyrase Inhibitors (MGIs), a subclass of Novel Bacterial Topoisomerase Inhibitors (NBTIs), were recently shown to be active against the tubercle bacillus. Here, we show that the MGI EC/11716 not only has potent anti-tubercular activity but is active against M. abscessus and M. avium in vitro . Focusing on M. abscessus , which causes the most difficult to cure NTM disease, we show that EC/11716 is bactericidal, active against drug-tolerant biofilms, and efficacious in a murine model of M. abscessus lung infection. Based on resistant mutant selection experiments, we report a low frequency of resistance to EC/11716 and confirm DNA gyrase as its target. Our findings demonstrate the potential of NBTIs as anti- M. abscessus and possibly broad spectrum anti-mycobacterial agents.

scholarly journals Inhibition of Neisseria gonorrhoeae Type II Topoisomerases by the Novel Spiropyrimidinetrione AZD0914

2015 ◽  
Vol 290 (34) ◽  
pp. 20984-20994 ◽  
Author(s):  
Gunther Kern ◽  
Tiffany Palmer ◽  
David E. Ehmann ◽  
Adam B. Shapiro ◽  
Beth Andrews ◽  
...  
Keyword(s):  
Neisseria Gonorrhoeae ◽  
Bacterial Species ◽  
Dna Gyrase ◽  
Resistant Mutant ◽  
Multidrug Resistant ◽  
Type Ii ◽  
Topoisomerase Iv ◽  
Gram Positive ◽  
Gram Negative

We characterized the inhibition of Neisseria gonorrhoeae type II topoisomerases gyrase and topoisomerase IV by AZD0914 (AZD0914 will be henceforth known as ETX0914 (Entasis Therapeutics)), a novel spiropyrimidinetrione antibacterial compound that is currently in clinical trials for treatment of drug-resistant gonorrhea. AZD0914 has potent bactericidal activity against N. gonorrhoeae, including multidrug-resistant strains and key Gram-positive, fastidious Gram-negative, atypical, and anaerobic bacterial species (Huband, M. D., Bradford, P. A., Otterson, L. G., Basrab, G. S., Giacobe, R. A., Patey, S. A., Kutschke, A. C., Johnstone, M. R., Potter, M. E., Miller, P. F., and Mueller, J. P. (2014) In Vitro Antibacterial Activity of AZD0914: A New Spiropyrimidinetrione DNA Gyrase/Topoisomerase Inhibitor with Potent Activity against Gram-positive, Fastidious Gram-negative, and Atypical Bacteria. Antimicrob. Agents Chemother. 59, 467–474). AZD0914 inhibited DNA biosynthesis preferentially to other macromolecules in Escherichia coli and induced the SOS response to DNA damage in E. coli. AZD0914 stabilized the enzyme-DNA cleaved complex for N. gonorrhoeae gyrase and topoisomerase IV. The potency of AZD0914 for inhibition of supercoiling and the stabilization of cleaved complex by N. gonorrhoeae gyrase increased in a fluoroquinolone-resistant mutant enzyme. When a mutation, conferring mild resistance to AZD0914, was present in the fluoroquinolone-resistant mutant, the potency of ciprofloxacin for inhibition of supercoiling and stabilization of cleaved complex was increased greater than 20-fold. In contrast to ciprofloxacin, religation of the cleaved DNA did not occur in the presence of AZD0914 upon removal of magnesium from the DNA-gyrase-inhibitor complex. AZD0914 had relatively low potency for inhibition of human type II topoisomerases α and β.

scholarly journals Expression of hamster P-glycoprotein and multidrug resistance in DNA-mediated transformants of mouse LTA cells.

1987 ◽  
Vol 7 (2) ◽  
pp. 718-724 ◽  
Author(s):  
K L Deuchars ◽  
R P Du ◽  
M Naik ◽  
D Evernden-Porelle ◽  
N Kartner ◽  
...  
Keyword(s):  
Multidrug Resistance ◽  
Dna Sequences ◽  
Multidrug Resistant ◽  
Cross Resistance ◽  
Recipient Mouse ◽  
Strongly Correlated ◽  
Wild Type ◽  
Glycoprotein P ◽  
Single Drug ◽  
P Glycoprotein

The overexpression of a plasma membrane glycoprotein, P-glycoprotein, is strongly correlated with the expression of multidrug resistance. This phenotype (frequently observed in cell lines selected for resistance to a single drug) is characterized by cross resistance to many drugs, some of which are used in cancer chemotherapy. In the present study we showed that DNA-mediated transformants of mouse LTA cells with DNA from multidrug-resistant hamster cells acquired the multidrug resistance phenotype, that the transformants contained hamster P-glycoprotein DNA sequences, that these sequences were amplified whereas the recipient mouse P-glycoprotein sequences remained at wild-type levels, and that the overexpressed P-glycoprotein in these cells was of hamster origin. Furthermore, we showed that the hamster P-glycoprotein sequences were transfected independently of a group of genes that were originally coamplified and linked within a 1-megabase-pair region in the donor hamster genome. These data indicate that the high expression of P-glycoprotein is the only alteration required to mediate multidrug resistance.

scholarly journals Mutations in the MAB_2299c TetR Regulator Confer Cross-Resistance to Clofazimine and Bedaquiline in Mycobacterium abscessus

2018 ◽  
Vol 63 (1) ◽  
Author(s):  
Matthias Richard ◽  
Ana Victoria Gutiérrez ◽  
Albertus Viljoen ◽  
Daniela Rodriguez-Rincon ◽  
Françoise Roquet-Baneres ◽  
...  
Keyword(s):  
Point Mutations ◽  
Multidrug Resistant ◽  
Mycobacterium Abscessus ◽  
Cross Resistance ◽  
Clinical Settings ◽  
Content Type ◽  
New Therapeutic Approaches ◽  
Resistant Tuberculosis ◽  
Multidrug Resistant Tuberculosis ◽  
Target Dna

ABSTRACT New therapeutic approaches are needed against Mycobacterium abscessus, a respiratory mycobacterial pathogen that evades efforts to successfully treat infected patients. Clofazimine and bedaquiline, two drugs used for the treatment of multidrug-resistant tuberculosis, are being considered as alternatives for the treatment of lung diseases caused by M. abscessus. With the aim to understand the mechanism of action of these agents in M. abscessus, we sought herein to determine the means by which M. abscessus can develop resistance. Spontaneous resistant strains selected on clofazimine, followed by whole-genome sequencing, identified mutations in MAB_2299c, encoding a putative TetR transcriptional regulator. Unexpectedly, mutants with these mutations were also cross-resistant to bedaquiline. MAB_2299c was found to bind to its target DNA, located upstream of the divergently oriented MAB_2300-MAB_2301 gene cluster, encoding MmpS/MmpL membrane proteins. Point mutations or deletion of MAB_2299c was associated with the concomitant upregulation of the mmpS and mmpL transcripts and accounted for this cross-resistance. Strikingly, deletion of MAB_2300 and MAB_2301 in the MAB_2299c mutant strain restored susceptibility to bedaquiline and clofazimine. Overall, these results expand our knowledge with respect to the regulatory mechanisms of the MmpL family of proteins and a novel mechanism of drug resistance in this difficult-to-treat respiratory mycobacterial pathogen. Therefore, MAB_2299c may represent an important marker of resistance to be considered in the treatment of M. abscessus diseases with clofazimine and bedaquiline in clinical settings.

scholarly journals Functional Analysis of DNA Gyrase Mutant Enzymes Carrying Mutations at Position 88 in the A Subunit Found in Clinical Strains of Mycobacterium tuberculosis Resistant to Fluoroquinolones

2006 ◽  
Vol 50 (12) ◽  
pp. 4170-4173 ◽  
Author(s):  
Stéphanie Matrat ◽  
Nicolas Veziris ◽  
Claudine Mayer ◽  
Vincent Jarlier ◽  
Chantal Truffot-Pernot ◽  
...  
Keyword(s):  
Mycobacterium Tuberculosis ◽  
Dna Gyrase ◽  
Multidrug Resistant ◽  
Site Directed Mutagenesis ◽  
Fluoroquinolone Resistance ◽  
Directed Mutagenesis ◽  
The Novel ◽  
Wild Type ◽  
Clinical Strains ◽  
A Subunit

ABSTRACT We investigated the enzymatic efficiency and inhibition by quinolones of Mycobacterium tuberculosis DNA gyrases carrying the previously described GyrA G88C mutation and the novel GyrA G88A mutation harbored by two multidrug-resistant clinical strains and reproduced by site-directed mutagenesis. Fluoroquinolone MICs and 50% inhibitory concentrations for both mutants were 2- to 43-fold higher than for the wild type, demonstrating that these mutations confer fluoroquinolone resistance in M. tuberculosis.

Ultrastructure of Chlamydomonas reinhardtii following exposure to paraquat: comparison of wild type and a paraquat-resistant mutant

1993 ◽  
Vol 71 (1) ◽  
pp. 174-182 ◽  
Author(s):  
Douglas F. Bray ◽  
John R. Bagu ◽  
Kazuo Nakamura
Keyword(s):  
Chlamydomonas Reinhardtii ◽  
Wild Type Strain ◽  
Single Gene ◽  
Resistant Mutant ◽  
Cross Resistance ◽  
Wild Type ◽  
Ultrastructural Examination ◽  
Unicellular Green Alga ◽  
Strain 137C ◽  
Mutant Cells

A mutant (NL-51) of the unicellular green alga Chlamydomonas reinhardtii Dangeard isolated from a wild-type strain (137c+) was shown to be resistant to the bipyridilium herbicide paraquat at the concentration at which growth of the wild type was inhibited. Tetrad analysis from a cross between the mutant and the wild type showed 2:2 segregation, indicating that the resistance is under control of a single gene. Cross-resistance of the mutant to methionine and to methionine combined with riboflavin suggested that the resistance is due to increased levels of one of the enzymes capable of detoxifying active oxygens. Ultrastructural examination of mutant and wild-type cells exposed to paraquat revealed that the mutant cells were 3 to 4 times more resistant, but both strains showed the same sequence of deterioration. Damage was first manifested as swelling of the mitochondria and dilation of the perinuclear space. This was followed by disintegration of the nuclear matrix and the chloroplast thylakoids. Key words: Chlamydomonas reinhardtii, methionine resistance, paraquat, paraquat-resistant mutant, ultrastructure.

scholarly journals Potent β-Lactam Enhancer Activity of Zidebactam and WCK 5153 against Acinetobacter baumannii, Including Carbapenemase-Producing Clinical Isolates

2017 ◽  
Vol 61 (11) ◽  
Author(s):  
Bartolome Moya ◽  
Isabel M. Barcelo ◽  
Sachin Bhagwat ◽  
Mahesh Patel ◽  
German Bou ◽  
...  
Keyword(s):  
Acinetobacter Baumannii ◽  
Multidrug Resistant ◽  
Antimicrobial Activities ◽  
Clinical Strain ◽  
Wild Type ◽  
Enhancer Activity ◽  
Content Type ◽  
Penicillin Binding Proteins ◽  
Time Kill

ABSTRACT Multidrug-resistant Acinetobacter baumannii has rapidly spread worldwide, resulting in a serious threat to hospitalized patients. Zidebactam and WCK 5153 are novel non-β-lactam bicyclo-acyl hydrazide β-lactam enhancer antibiotics being developed to target multidrug-resistant A. baumannii. The objectives of this work were to determine the 50% inhibitory concentrations (IC50s) for penicillin-binding proteins (PBP), the OXA-23 inhibition profiles, and the antimicrobial activities of zidebactam and WCK 5153, alone and in combination with β-lactams, against multidrug-resistant A. baumannii. MICs and time-kill kinetics were determined for an A. baumannii clinical strain producing the carbapenemase OXA-23 and belonging to the widespread European clone II of sequence type 2 (ST2). Inhibition of the purified OXA-23 enzyme by zidebactam, WCK 5153, and comparators was assessed. All of the compounds tested displayed apparent Ki values of >100 μM, indicating poor OXA-23 β-lactamase inhibition. The IC50s of zidebactam, WCK 5153, cefepime, ceftazidime, meropenem, and sulbactam (range of concentrations tested, 0.02 to 2 μg/ml) for PBP were also determined. Zidebactam and WCK 5153 demonstrated specific high-affinity binding to PBP2 of A. baumannii (0.01 μg/ml for both of the compounds). The MICs of zidebactam and WCK 5153 were >1,024 μg/ml for wild-type and multidrug-resistant Acinetobacter strains. Importantly, combinations of cefepime with 8 μg/ml of zidebactam or WCK 5153 and sulbactam with 8 μg/ml of zidebactam or WCK 5153 led to 4- and 8-fold reductions of the MICs, respectively, and showed enhanced killing. Notably, several of the combinations resulted in full bacterial eradication at 24 h. We conclude that zidebactam and WCK 5153 are PBP2 inhibitors that show a potent β-lactam enhancer effect against A. baumannii, including a multidrug-resistant OXA-23-producing ST2 international clone.

scholarly journals Cross-Resistance between Triclosan and Antibiotics inPseudomonas aeruginosa Is Mediated by Multidrug Efflux Pumps: Exposure of a Susceptible Mutant Strain to Triclosan Selects nfxB Mutants Overexpressing MexCD-OprJ

2001 ◽  
Vol 45 (2) ◽  
pp. 428-432 ◽  
Author(s):  
Rungtip Chuanchuen ◽  
Kerry Beinlich ◽  
Tung T. Hoang ◽  
Anna Becher ◽  
RoxAnn R. Karkhoff-Schweizer ◽  
...  
Keyword(s):  
Acyl Carrier Protein ◽  
Regulatory Gene ◽  
Multidrug Resistant ◽  
Cross Resistance ◽  
Resistant Bacteria ◽  
Wild Type ◽  
Multidrug Efflux ◽  
Efflux System ◽  
High Frequencies ◽  
Multidrug Efflux Pumps

ABSTRACT Triclosan is an antiseptic frequently added to items as diverse as soaps, lotions, toothpaste, and many commonly used household fabrics and plastics. Although wild-type Pseudomonas aeruginosaexpresses the triclosan target enoyl-acyl carrier protein reductase, it is triclosan resistant due to expression of the MexAB-OprM efflux system. Exposure of a susceptible Δ(mexAB-oprM) strain to triclosan selected multidrug-resistant bacteria at high frequencies. These bacteria hyperexpressed the MexCD-OprJ efflux system due to mutations in its regulatory gene, nfxB. The MICs of several drugs for these mutants were increased up to 500-fold, including the MIC of ciprofloxacin, which was increased 94-fold. Whereas the MexEF-OprN efflux system also participated in triclosan efflux, this antimicrobial was not a substrate for MexXY-OprM.

scholarly journals In Vitro and In Vivo Activities of TP0480066, a Novel Topoisomerase Inhibitor, against Neisseria gonorrhoeae

2021 ◽  
Author(s):  
Aiko Masuko ◽  
Iichiro Takata ◽  
Kiyoko Fujita ◽  
Hirotoshi Okumura ◽  
Fumihito Ushiyama ◽  
...  
Keyword(s):  
Neisseria Gonorrhoeae ◽  
Antimicrobial Agent ◽  
Transmitted Disease ◽  
Dna Gyrase ◽  
Multidrug Resistant ◽  
Cross Resistance ◽  
Topoisomerase Iv ◽  
Sexually Transmitted

Gonorrhea is a common, sexually transmitted disease caused by Neisseria gonorrhoeae. Multidrug-resistant N. gonorrhoeae is an urgent threat, and the development of a new antimicrobial agent that functions via a new mechanism is strongly desired. We evaluated the in vitro and in vivo activities of a DNA gyrase/topoisomerase IV inhibitor, TP0480066, which is a novel 8-(methylamino)-2-oxo-1,2-dihydroquinoline derivative. The MICs of TP0480066 were substantially lower than those of other currently or previously used antimicrobials against gonococcal strains demonstrating resistance to fluoroquinolones, macrolides, β-lactams and aminoglycosides (MICs, ≤0.0005 μg/mL). Additionally, no cross-resistance was observed between TP0480066 and ciprofloxacin. The frequencies of spontaneous resistance to TP0480066 for N. gonorrhoeae ATCC 49226 were below the detection limit (<2.4 × 10−10) at concentrations equivalent to 32 × MIC. TP0480066 also showed potent in vitro bactericidal activity and in vivo efficacy in a mouse model of N. gonorrhoeae infection. These data suggest that TP0480066 is a candidate antimicrobial agent for gonococcal infections.

Sign in / Sign up

Export Citation Format

Share Document