1
|
Khurana P, Pulicharla R, Brar SK. Imipenem-metal complexes: Computational analysis and toxicity studies with wastewater model microorganisms. ENVIRONMENTAL RESEARCH 2023; 239:117275. [PMID: 37827363 DOI: 10.1016/j.envres.2023.117275] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2023] [Revised: 09/24/2023] [Accepted: 09/28/2023] [Indexed: 10/14/2023]
Abstract
The occurrence of antibiotic residues in diverse water sources has long been acknowledged as a potential health concern due to the emergence and spread of antibiotic-resistant bacteria and genes. However, there have been limited studies into the presence of antibiotic-metal complexes (AMCs) in real-time wastewater matrices, and their impact on wastewater microbial communities. The present work, in this regard, investigated the stability of Imipenem-metal complexes (Me = Mg (II), Ca (II), Fe (II), Cu (II), and Al (III)) with computational studies, stoichiometry with potentiometric measurements, and their antibacterial activity towards wastewater model microorganisms- Bacillus subtilis (B. subtilis) and Escherichia coli (E. Coli) by Colony Forming Unit (CFU) method. The lower energy of Imipenem-metal complexes than the parent antibiotic- Imipenem, during energy optimization using density functional (DFT) methods, revealed that metal interactions of Imipenem stabilize the drug by minimizing its energy. Further, CFU studies indicated that these complexes display higher antimicrobial activity than parent antibiotics. The electron delocalization over the entire chelated system (AMCs) reduces polarity and increases the lipophilicity of the complexes, thereby facilitating stronger interaction between AMCs and the bacterial cell membrane. Results indicate increased antibacterial activity of Imipenem-metal complexes for both E. coli and B. subtilis. The antibacterial activity, was however, more pronounced in B. subtilis, with >97% growth inhibition for metal complexes of Imipenem (at a Minimum Inhibitory Concentration of 20 nM or 6 ppb (i.e., MIC90)), for both the stoichiometric ratios (metal to ligand) ratios (M: L 1: 1 and 2: 1). All around, with increased stability and toxicity, AMCs are emerging as contaminants of concern and demand immediate attention to devise methods for their removal.
Collapse
Affiliation(s)
- Pratishtha Khurana
- Department of Civil Engineering, Lassonde School of Engineering, York University, North York, Toronto, Ontario M3J 1P3, Canada
| | - Rama Pulicharla
- Department of Civil Engineering, Lassonde School of Engineering, York University, North York, Toronto, Ontario M3J 1P3, Canada
| | - Satinder Kaur Brar
- Department of Civil Engineering, Lassonde School of Engineering, York University, North York, Toronto, Ontario M3J 1P3, Canada.
| |
Collapse
|
2
|
Mumtaz L, Farid A, Yousef Alomar S, Ahmad N, Nawaz A, Andleeb S, Amin A. Assesment of polyphenolic compounds against biofilms produced by clinical Acinetobacter baumannii strains using in silico and in vitro models. Saudi J Biol Sci 2023; 30:103743. [PMID: 37564783 PMCID: PMC10410175 DOI: 10.1016/j.sjbs.2023.103743] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2023] [Revised: 07/05/2023] [Accepted: 07/14/2023] [Indexed: 08/12/2023] Open
Abstract
Several types of microbial infections are caused by Acinetobacter baumanii that has developed resistance to antimicrobial agents. We therefore investigated the role of plant polyphenols against A. baumannii using in silico and in vitro models. The clinical strains of A. baumannii were investigated for determination of resistance pattern and resistance mechanisms including efflux pump, extended spectrum beta lactamase, phenotype detection of AmpC production, and Metallo-β-lactamase. The polyphenolic compounds were docked against transcription regulator BfmR (PDB ID 6BR7) and antimicrobial, antibiofilm, and anti-quorum sensing activities were performed. The antibiogram studies showed that all isolated strains were resistant. Strain A77 was positive in Metallo-β-lactamase production. Similarly, none of strains were producers of AmpC, however, A77, A76, A75 had active efflux pumps. Molecular docking studies confirmed a strong binding affinity of Rutin and Catechin towards transcription regulator 6BR7. A significant antimicrobial activity was recorded in case of quercetin and syringic acid (MIC 3.1 µg/mL) followed by vanillic acid and caffeic acid (MIC 12.5 µg/mL). All tested compounds presented a strong antibiofilm activity against A. baumanii strain A77 (65 to 90%). It was concluded that all tested polyphenols samples posess antimicrobial and antibiofilm activities, and hence they may be utilized to treat multidrug resistance A. baumannii infections.
Collapse
Affiliation(s)
- Laraib Mumtaz
- Gomal Centre of Biochemistry and Biotechnology(GCBB), Gomal University, KPK, 29050 D.I.Khan, Pakistan
- Gomal Centre of Pharmaceutical Sciences, Faculty of Pharmacy, Gomal University, D.I.Khan 29050, Pakistan
| | - Arshad Farid
- Gomal Centre of Biochemistry and Biotechnology(GCBB), Gomal University, KPK, 29050 D.I.Khan, Pakistan
| | - Suliman Yousef Alomar
- Doping Research Chair, Zoology Department, College of Science, King Saud University, Riyadh 11451, Saudi Arabia
| | - Naushad Ahmad
- Department of Chemistry, College of Science, King Saud University, Riyadh 11451, Saudi Arabia
| | - Asif Nawaz
- Gomal Centre of Pharmaceutical Sciences, Faculty of Pharmacy, Gomal University, D.I.Khan 29050, Pakistan
| | - Saadia Andleeb
- Atta Ur Rehman School of Biological Sciences, National University of Science and Technology, Islamabad Pakistan
| | - Adnan Amin
- Gomal Centre of Pharmaceutical Sciences, Faculty of Pharmacy, Gomal University, D.I.Khan 29050, Pakistan
| |
Collapse
|
3
|
Ethidium Binding to Salmonella enterica ser. Typhimurium Cells and Salmon Sperm DNA. Molecules 2021; 26:molecules26113386. [PMID: 34205065 PMCID: PMC8199877 DOI: 10.3390/molecules26113386] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2021] [Revised: 05/26/2021] [Accepted: 05/31/2021] [Indexed: 11/17/2022] Open
Abstract
Bacterial resistance to antibiotics due to increased efficiency of the efflux is a serious problem in clinics of infectious diseases. Knowledge of the factors affecting the activity of efflux pumps would help to find the solution. For this, fast and trustful methods for efflux analysis are needed. Here, we analyzed how the assay conditions affect the accumulation of efflux indicators ethidium (Et+) and tetraphenylphosphonium in Salmonella enterica ser. Typhimurium cells. An inhibitor phenylalanyl-arginyl-β-naphtylamide was applied to evaluate the input of RND family pumps into the total efflux. In parallel to spectrofluorimetric analysis, we used an electrochemical assessment of Et+ concentration. The results of our experiments indicated that Et+ fluorescence increases immediately after the penetration of this indicator into the cells. However, when cells bind a high amount of Et+, the intensity of the fluorescence reaches the saturation level and stops reacting to the accumulated amount of this indicator. For this reason, electrochemical measurements provide more trustful information about the efficiency of efflux when cells accumulate high amounts of Et+. Measurements of Et+ interaction with the purified DNA demonstrated that the affinity of this lipophilic cation to DNA depends on the medium composition. The capacity of DNA to bind Et+ considerably decreases in the presence of Mg2+, Polymyxin B or when DNA is incubated in high ionic strength media.
Collapse
|
4
|
The effect of EDTA in combination with some antibiotics against clinical isolates of gram negative bacteria in Mansoura, Egypt. Microb Pathog 2021; 154:104840. [PMID: 33691177 DOI: 10.1016/j.micpath.2021.104840] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Revised: 01/10/2021] [Accepted: 02/16/2021] [Indexed: 11/24/2022]
Abstract
Extensive use of antibiotics in clinical practice has been associated with increasing frequency of resistant microorganisms. So new strategy is needed to treat the resistant pathogens. Hence this study was conducted to determine the effect of Ethylenediaminetetraacetic acid (EDTA) in increasing the inhibition effect of some antibiotics on multi-drug resistant (MDR) gram-negative bacteria. For this purpose, 40 E. coli isolates, 40 K. pneumoniae isolates and 50 P. aeruginosa isolates were collected from different University's hospitals in Mansoura, Egypt. Antibacterial susceptibility pattern against 9 different antimicrobials were studied by disc diffusion method. Also the effect of two sub-inhibitory concentrations of EDTA (1 and 2 mM) on the inhibition zones of antibiotic discs against the highly multidrug resistant (MDR) isolates was determined. Checkerboard method was used for testing the activity of gentamicin/EDTA and cefotaxime/EDTA combinations on the highly MDR isolates. Additionally, the effect of EDTA on the expression of efflux pump genes was tested by real time-PCR. Most of the clinical isolates were found to be resistant to the tested antibiotics except imipenem and high prevalence of MDR isolates was recorded. 34 isolates were selected as those showed the highest multi-drug resistance and were tested to specify their MIC for EDTA as EDTA showed strong antibacterial activity with MIC ranging 4-8 mM. The addition of sub-MIC of EDTA (1or 2 mM) to the agar plate resulted in changing the 11 tested E. coli isolates from resistant to sensitive to ceftazidime, gentamicin, rifampin, ampicillin, erythromycin and vancomycin, the tested K. pneumoniae isolates were turned also from resistant to sensitive to gentamicin and ceftazidime, additionally the tested P. aeruginosa isolates became sensitive to gentamicin, ceftazidime and ciprofloxacin. Indifference to additive activity was observed for tested combinations and MIC value of cefotaxime or gentamicin in combination with EDTA was less than antibiotic alone in the most tested isolates. Moreover, significant reduction (P < 0.01) in the expression of all tested efflux pump genes in treated E. coli, K. pneumoniae and P. aeruginosa isolates with EDTA compared to untreated isolates was observed. In conclusion, these results suggest that the combination of antibiotic especially gentamicin with EDTA may be fruitful for management of resistant gram negative infections.
Collapse
|
5
|
Wu VM, Huynh E, Tang S, Uskoković V. Calcium phosphate nanoparticles as intrinsic inorganic antimicrobials: mechanism of action. Biomed Mater 2020; 16:015018. [DOI: 10.1088/1748-605x/aba281] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
|
6
|
Nava AR, Mauricio N, Sanca AJ, Domínguez DC. Evidence of Calcium Signaling and Modulation of the LmrS Multidrug Resistant Efflux Pump Activity by Ca 2 + Ions in S. aureus. Front Microbiol 2020; 11:573388. [PMID: 33193178 PMCID: PMC7642317 DOI: 10.3389/fmicb.2020.573388] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Accepted: 09/14/2020] [Indexed: 12/19/2022] Open
Abstract
Calcium ions (Ca2+) play a pivotal role in eukaryote cell signaling and regulate many physiological functions. Although a similar role for Ca2+ in prokaryotes has been difficult to demonstrate, there is increasing evidence for Ca2+ as a cell regulator in bacteria. The purpose of this study was to investigate Ca2+ signaling and the effect of Ca2+ on the Staphylococcus aureus multidrug resistant efflux pump LmrS. We hypothesized that antibiotics act by increasing Ca2+ concentrations, which in turn enhance the efflux activity of LmrS. These Ca2+ transients were measured by luminometry in response to various antibiotics by using the photoprotein aequorin reconstituted within live bacterial cells. Efflux associated with LmrS was measured by the increase in fluorescence due to the loss of ethidium bromide (EtBr) from both S. aureus cells and from E. coli cells in which the lmrs gene of S. aureus was expressed. We found that addition of antibiotics to cells generated unique cytosolic Ca2+ transients and that addition of CaCl2 to cells enhanced EtBr efflux whereas addition of Ca2+ chelators or efflux pump inhibitors significantly decreased EtBr efflux from cells. We conclude that antibiotics induce a Ca2+ mediated response through transients in cytosolic Ca2+, which then stimulates LmrS efflux pump.
Collapse
Affiliation(s)
- Amy R Nava
- Department of Interdisciplinary Health Sciences, The University of Texas at El Paso, El Paso, TX, United States
| | - Natalia Mauricio
- Biology Department, El Paso Community College, El Paso, TX, United States
| | - Angel J Sanca
- Biological Sciences Department, The University of Texas at El Paso, El Paso, TX, United States
| | - Delfina C Domínguez
- Department of Interdisciplinary Health Sciences, The University of Texas at El Paso, El Paso, TX, United States.,Clinical Laboratory Science Program/Department of Public Health Sciences, The University of Texas at El Paso, El Paso, TX, United States
| |
Collapse
|
7
|
Guo RH, Gong Y, Kim SY, Rhee JH, Kim YR. DIDS inhibits Vibrio vulnificus cytotoxicity by interfering with TolC-mediated RtxA1 toxin secretion. Eur J Pharmacol 2020; 884:173407. [PMID: 32735984 DOI: 10.1016/j.ejphar.2020.173407] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Revised: 07/10/2020] [Accepted: 07/23/2020] [Indexed: 12/28/2022]
Abstract
Vibrio vulnificus (V. vulnificus) infection, frequently resulting in fatal septicemia, has become a growing health concern worldwide. The present study aimed to explore the potential agents that could protect against V. vulnificus cytotoxicity, and to analyze the possible underlying mechanisms. First, we observed that 4,4'-diisothiocyanatostilbene-2,2'-disulfonic acid disodium salt hydrate (DIDS) significantly suppressed V. vulnificus cytotoxicity to host cells by using a lactate dehydrogenase (LDH) assay. DIDS did not exhibit any effect on host cell viability, bacterial growth, microbial adhesion and swarming motility. DIDS effectively lowered V. vulnificus RtxA1 toxin-induced calcium influx into host mitochondria and RtxA1 binding to host cells. To further elucidate the underlying mechanism, the synthesis and secretion of RtxA1 toxin were investigated by Western blotting. Intriguingly, DIDS selectively inhibited the secretion of RtxA1 toxin, but did not influence its synthesis. Consequently, the outer membrane portal TolC, a key conduit for RtxA1 export coupled with tripartite efflux pumps, was examined by RT-PCR and Western blotting. We found that DIDS significantly reduced the expression of TolCV1 protein at the transcriptional level. Taken together, these results suggest that DIDS is a promising new paradigm as an antimicrobial drug that targets TolC-mediated toxin.
Collapse
Affiliation(s)
- Rui Hong Guo
- College of Pharmacy and Research Institute of Drug Development, Chonnam National University, Republic of Korea
| | - Yue Gong
- College of Pharmacy and Research Institute of Drug Development, Chonnam National University, Republic of Korea
| | - Soo Young Kim
- Clinical Vaccine R&D Center and Department of Microbiology, Chonnam National University Medical School, Republic of Korea
| | - Joon Haeng Rhee
- Clinical Vaccine R&D Center and Department of Microbiology, Chonnam National University Medical School, Republic of Korea
| | - Young Ran Kim
- College of Pharmacy and Research Institute of Drug Development, Chonnam National University, Republic of Korea.
| |
Collapse
|
8
|
Grimsey EM, Piddock LJV. Do phenothiazines possess antimicrobial and efflux inhibitory properties? FEMS Microbiol Rev 2020; 43:577-590. [PMID: 31216574 DOI: 10.1093/femsre/fuz017] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2019] [Accepted: 06/12/2019] [Indexed: 12/30/2022] Open
Abstract
Antibiotic resistance is a global health concern; the rise of drug-resistant bacterial infections is compromising the medical advances that resulted from the introduction of antibiotics at the beginning of the 20th century. Considering that the presence of mutations within individuals in a bacterial population may allow a subsection to survive and propagate in response to selective pressure, as long as antibiotics are used in the treatment of bacterial infections, development of resistance is an inevitable evolutionary outcome. This, combined with the lack of novel antibiotics being released to the clinical market, means the need to develop alternative strategies to treat these resistant infections is critical. We discuss how the use of antibiotic adjuvants can minimise the appearance and impact of resistance. To this effect, several phenothiazine-derived drugs have been shown to potentiate the activities of antibiotics used to treat infections caused by Gram-positive and Gram-negative bacteria. Outside of their role as antipsychotic medications, we review the evidence to suggest that phenothiazines possess inherent antibacterial and efflux inhibitory properties enabling them to potentially combat drug resistance. We also discuss that understanding their mode of action is essential to facilitate the design of new phenothiazine derivatives or novel agents for use as antibiotic adjuvants.
Collapse
Affiliation(s)
- Elizabeth M Grimsey
- Institute of Microbiology & Infection, College of Medical & Dental Sciences, University of Birmingham, Edgbaston, United Kingdom
| | - Laura J V Piddock
- Institute of Microbiology & Infection, College of Medical & Dental Sciences, University of Birmingham, Edgbaston, United Kingdom
| |
Collapse
|
9
|
Nové M, Kincses A, Molnár J, Amaral L, Spengler G. The Role of Efflux Pumps and Environmental pH in Bacterial Multidrug Resistance. In Vivo 2020; 34:65-71. [PMID: 31882464 DOI: 10.21873/invivo.11746] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Revised: 10/03/2019] [Accepted: 10/11/2019] [Indexed: 12/13/2022]
Abstract
BACKGROUND/AIM One of the most studied bacterial resistance mechanisms is the resistance related to multidrug efflux pumps. In our study the pump activity of the Escherichia coli K-12 AG100 strain expressing the AcrAB-TolC pump system was investigated at pH 7 and pH 5 in the presence of the efflux pump inhibitor (EPI) promethazine (PMZ). MATERIALS AND METHODS The EPI activity was assessed by real-time fluorimetry. The influence of PMZ treatment on the relative expression of the pump genes acrA, acrB and their regulators marA, marB, marR, the stress genes soxS, rob, as well as the bacterial growth control genes ftsI, and sdiA were determined by RT-qPCR. RESULTS The EPI activity of PMZ was more effective at neutral pH. The PMZ treatment induced a significant stress response in the bacterium at acidic pH by the up-regulation of genes. CONCLUSION The genetic system that regulates the activity of the main efflux pump is pH-dependent.
Collapse
Affiliation(s)
- Márta Nové
- Department of Medical Microbiology and Immunobiology, Faculty of Medicine, University of Szeged, Szeged, Hungary
| | - Annamária Kincses
- Department of Medical Microbiology and Immunobiology, Faculty of Medicine, University of Szeged, Szeged, Hungary
| | - József Molnár
- Department of Medical Microbiology and Immunobiology, Faculty of Medicine, University of Szeged, Szeged, Hungary
| | - Leonard Amaral
- Department of Medical Microbiology and Immunobiology, Faculty of Medicine, University of Szeged, Szeged, Hungary.,Travel Medicine, Institute of Hygiene and Tropical Medicine, Universidade Nova de Lisboa, Lisbon, Portugal
| | - Gabriella Spengler
- Department of Medical Microbiology and Immunobiology, Faculty of Medicine, University of Szeged, Szeged, Hungary
| |
Collapse
|
10
|
Abstract
Efflux is an important mechanism in Gram-negative bacteria conferring multidrug resistance. Inhibition of efflux is an encouraging strategy to restore the antibacterial activity of antibiotics. Chlorpromazine and amitriptyline have been shown to behave as efflux inhibitors. However, their mode of action is poorly understood. Exposure of Salmonella enterica serovar Typhimurium and Escherichia coli to chlorpromazine selected for mutations within genes encoding RamR and MarR, regulators of the multidrug tripartite efflux pump AcrAB-TolC. Further experiments with S. Typhimurium containing AcrB D408A (a nonfunctional efflux pump) and chlorpromazine or amitriptyline resulted in the reversion of the mutant acrB allele to the wild type. Together, this suggests these drugs are AcrB efflux substrates. Subsequent docking studies with AcrB from S. Typhimurium and E. coli, followed by molecular dynamics simulations and free energy calculations showed that chlorpromazine and amitriptyline bind at the hydrophobic trap, a preferred binding site for substrates and inhibitors within the distal binding pocket of AcrB. Based on these simulations, we suggest that chlorpromazine and amitriptyline inhibit AcrB-mediated efflux by interfering with substrate binding. Our findings provide evidence that these drugs are substrates and inhibitors of AcrB, yielding molecular details of their mechanism of action and informing drug discovery of new efflux inhibitors.IMPORTANCE Efflux pumps of the resistance nodulation-cell division (RND) superfamily are major contributors to multidrug resistance for most of the Gram-negative ESKAPE (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter species) pathogens. The development of inhibitors of these pumps would be highly desirable; however, several issues have thus far hindered all efforts at designing new efflux inhibitory compounds devoid of adverse effects. An alternative route to de novo design relies on the use of marketed drugs, for which side effects on human health have been already assessed. In this work, we provide experimental evidence that the antipsychotic drugs chlorpromazine and amitriptyline are inhibitors of the AcrB transporter, the engine of the major RND efflux pumps in Escherichia coli and Salmonella enterica serovar Typhimurium. Furthermore, in silico calculations have provided a molecular-level picture of the inhibition mechanism, allowing rationalization of experimental data and paving the way for similar studies with other classes of marketed compounds.
Collapse
|
11
|
Scheel RA, Fusi AD, Min BC, Thomas CM, Ramarao BV, Nomura CT. Increased Production of the Value-Added Biopolymers Poly( R-3-Hydroxyalkanoate) and Poly(γ-Glutamic Acid) From Hydrolyzed Paper Recycling Waste Fines. Front Bioeng Biotechnol 2019; 7:409. [PMID: 31921814 PMCID: PMC6930151 DOI: 10.3389/fbioe.2019.00409] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2019] [Accepted: 11/27/2019] [Indexed: 11/25/2022] Open
Abstract
Reject fines, a waste stream of short lignocellulosic fibers produced from paper linerboard recycling, are a cellulose-rich paper mill byproduct that can be hydrolyzed enzymatically into fermentable sugars. In this study, the use of hydrolyzed reject fines as a carbon source for bacterial biosynthesis of poly(R-3-hydroxyalkanoate) (PHA) and poly(γ-glutamic acid) (PGA) was investigated. Recombinant Escherichia coli harboring PHA biosynthesis genes were cultivated with purified sugars or crude hydrolysate to produce both poly(R-3-hydroxybutyrate) (PHB) homopolymer and medium chain length-containing copolymer (PHB-co-MCL). Wild-type Bacillus licheniformis WX-02 were cultivated with crude hydrolysate to produce PGA. Both PHB and short chain-length-co-medium chain-length (SCL-co-MCL) PHA yields from crude hydrolysate were a 2-fold improvement over purified sugars, and the MCL monomer fraction was decreased slightly in copolymers produced from crude hydrolysate. PGA yield from crude hydrolysate was similarly increased 2-fold. The results suggest that sugars from hydrolyzed reject fines are a viable carbon source for PHA and PGA biosynthesis. The use of crude hydrolysate is not only possible but beneficial for biopolymer production, eliminating the need for costly separation and purification techniques. This study demonstrates the potential to divert a lignocellulosic waste stream into valuable biomaterials, mitigating the environmental impacts of solid waste disposal.
Collapse
Affiliation(s)
- Ryan A Scheel
- Department of Chemistry, State University of New York College of Environmental Science and Forestry, Syracuse, NY, United States
| | - Alexander D Fusi
- Department of Chemistry, State University of New York College of Environmental Science and Forestry, Syracuse, NY, United States
| | - Byeong C Min
- Department of Paper and Bioprocess Engineering, State University of New York College of Environmental Science and Forestry, Syracuse, NY, United States
| | - Christopher M Thomas
- Department of Paper and Bioprocess Engineering, State University of New York College of Environmental Science and Forestry, Syracuse, NY, United States
| | - Bandaru V Ramarao
- Department of Paper and Bioprocess Engineering, State University of New York College of Environmental Science and Forestry, Syracuse, NY, United States
| | - Christopher T Nomura
- Department of Chemistry, State University of New York College of Environmental Science and Forestry, Syracuse, NY, United States.,Center for Applied Microbiology, State University of New York College of Environmental Science and Forestry, Syracuse, NY, United States
| |
Collapse
|
12
|
Lima WG, Ramos-Alves MC, Soares AC. Dos distúrbios psiquiátricos à antibioticoterapia: reposicionamento da clorpromazina como agente antibacteriano. ACTA ACUST UNITED AC 2019. [DOI: 10.15446/rcciquifa.v48n1.80062] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
O alarmante aumento na taxa de resistência aos antibióticos põe em check à eficácia da terapia antibacteriana futura. Em contrapartida, as indústrias farmacêuticas negligenciam os investimentos em pesquisa e desenvolvimento de novos fármacos antimicrobianos em virtude de questões financeiras, legais e farmacológicas. Assim sendo, o reposicionamento de agentes disponíveis clinicamente torna-se uma promissora ferramenta para tentar driblar o desinteresse das indústrias. O fármaco antipsicótico clorpromazina (CPZ) destaca-se por possuir uma ampla faixa de atividade antibacteriana, a qual cobre desde patógenos Gram-positivos e Gram-negativos, até as micobactérias. A atividade antibacteriana é independente do perfil de susceptibilidade do microrganismo, sendo ela mantida mesmo em cepas altamente resistentes aos antibióticos. Alguns estudos mostram que mesmo nas concentrações clinicamente disponíveis no plasma (entre 0,1-0,5 μg/mL), a CPZ é capaz de matar Staphylococcus aureus e Mycobacterium tuberculosis dentro dos macrófagos. Em adição, estudos clínicos têm revelado os benefícios do uso da CPZ na terapia de suporte para pacientes com infecções em curso. Em conclusão, a CPZ pode eventualmente ser direcionada ao arsenal terapêutico antimicrobiano, especialmente no manejo das infecções causadas por microrganismos intracelulares com fenótipo multirresistente.
Collapse
|
13
|
Antistaphylococcal and Antibiotic Resistance Modulatory Activities of Thirteen Cameroonian Edible Plants against Resistant Phenotypes. Int J Microbiol 2018; 2018:1920198. [PMID: 30057614 PMCID: PMC6051259 DOI: 10.1155/2018/1920198] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2018] [Accepted: 06/06/2018] [Indexed: 11/26/2022] Open
Abstract
Background In this study, 18 methanol extracts from Cameroonian edible plants were tested for their antibacterial activities against 26 strains of S. aureus; the role of efflux pumps in the resistance of tested bacteria and the antibiotic resistance-modulating activities against selected multidrug-resistant (MDR) phenotypes were also investigated. Methods Broth microdilution assay was used to evaluate the antibacterial activity, the role of efflux pumps, and the antibiotic resistance-modulating effects of plant extracts. Results Extracts from Dacryodes edulis seeds (DES) and Dacryodes edulis bark (DEB) were active against all 26 tested bacterial strains, within the minimal inhibitory concentration (MIC) range of 256–1024 µg/mL. MIC values varied from 64 to 1024 µg/mL against 96.2% of the 26 tested bacteria for Phaseolus vulgaris leaves (PVL), 92.3% for Azadirachta indica bark (AIB), Dacryodes edulis leaves (DEL), and Ricinodendron heudelotii leaves (RHL). The lowest MIC value of 64 µg/mL was obtained with the extract from Cucurbita maxima beans (CMB) against MRSA4 strain and from Uapaca guineensis bark (UGB) against MRSA9 strain. Bacterial efflux pump inhibitor (EPI), carbonyl cyanide m-chlorophenyl hydrazone (CCCP), improved the activity of DES and UGB as well as that of extracts from Hibiscus esculentus leaves (HEL) and Uapaca guineensis leaves (UGL) against resistant S. aureus strains. Antibiotic-modulating effects against more than 70% of the S. aureus strains tested were obtained when RHL (at MIC/2) was combined with CIP, ERY, and KAN (88.89%), CHL (88.89%), TET (77.78%), and STR (88.89%). Conclusion The present study demonstrated that the 13 tested plants had antistaphylococcal effects and that DES, HEL, UGL, and UGB could be used in combination with EPI to combat resistance to Staphylococcus aureus. Also, it demonstrated that some studied extracts and mostly RHL could be used as antibiotic resistance modulators to fight against resistant strains of S. aureus.
Collapse
|
14
|
Kochan TJ, Somers MJ, Kaiser AM, Shoshiev MS, Hagan AK, Hastie JL, Giordano NP, Smith AD, Schubert AM, Carlson PE, Hanna PC. Intestinal calcium and bile salts facilitate germination of Clostridium difficile spores. PLoS Pathog 2017; 13:e1006443. [PMID: 28704538 PMCID: PMC5509370 DOI: 10.1371/journal.ppat.1006443] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2017] [Accepted: 06/03/2017] [Indexed: 12/26/2022] Open
Abstract
Clostridium difficile (C. difficile) is an anaerobic gram-positive pathogen that is the leading cause of nosocomial bacterial infection globally. C. difficile infection (CDI) typically occurs after ingestion of infectious spores by a patient that has been treated with broad-spectrum antibiotics. While CDI is a toxin-mediated disease, transmission and pathogenesis are dependent on the ability to produce viable spores. These spores must become metabolically active (germinate) in order to cause disease. C. difficile spore germination occurs when spores encounter bile salts and other co-germinants within the small intestine, however, the germination signaling cascade is unclear. Here we describe a signaling role for Ca2+ during C. difficile spore germination and provide direct evidence that intestinal Ca2+ coordinates with bile salts to stimulate germination. Endogenous Ca2+ (released from within the spore) and a putative AAA+ ATPase, encoded by Cd630_32980, are both essential for taurocholate-glycine induced germination in the absence of exogenous Ca2+. However, environmental Ca2+ replaces glycine as a co-germinant and circumvents the need for endogenous Ca2+ fluxes. Cd630_32980 is dispensable for colonization in a murine model of C. difficile infection and ex vivo germination in mouse ileal contents. Calcium-depletion of the ileal contents prevented mutant spore germination and reduced WT spore germination by 90%, indicating that Ca2+ present within the gastrointestinal tract plays a critical role in C. difficile germination, colonization, and pathogenesis. These data provide a biological mechanism that may explain why individuals with inefficient intestinal calcium absorption (e.g., vitamin D deficiency, proton pump inhibitor use) are more prone to CDI and suggest that modulating free intestinal calcium is a potential strategy to curb the incidence of CDI. The anaerobic, spore-forming bacterium Clostridium difficile (C. difficile) is a prominent pathogen in hospitals worldwide and the leading cause of nosocomial diarrhea. Numerous risk factors are associated with C. difficile infections (CDIs) including: antibiotics, advanced age, vitamin D deficiency, and proton pump inhibitors. Antibiotic use disrupts the intestinal microbiota allowing for C. difficile to colonize, however, why these other risk factors increase CDI incidence is unclear. Notably, deficient intestinal calcium absorption (i.e., increased calcium levels) is associated with these risk factors. In this work, we investigate the role of calcium in C. difficile spore germination. C. difficile spores are the infectious particles and they must become metabolically active (germinate) to cause disease. Here, we show that calcium is required for C. difficile germination, specifically activating the key step of cortex hydrolysis, and that this calcium can be derived from either within the spore or the environment. We also demonstrate that intestinal calcium is required for efficient spore germination in vivo, suggesting that intestinal concentrations of other co-germinants are insufficient to induce C. difficile germination. Collectively, these data provide a mechanism that explains the strong clinical correlations between increased intestinal calcium levels and risk of CDI.
Collapse
Affiliation(s)
- Travis J. Kochan
- University of Michigan Medical School, Department of Microbiology and Immunology. Ann Arbor, Michigan, United States of America
| | - Madeline J. Somers
- University of Michigan Medical School, Department of Microbiology and Immunology. Ann Arbor, Michigan, United States of America
| | - Alyssa M. Kaiser
- University of Michigan Medical School, Department of Microbiology and Immunology. Ann Arbor, Michigan, United States of America
| | - Michelle S. Shoshiev
- University of Michigan Medical School, Department of Microbiology and Immunology. Ann Arbor, Michigan, United States of America
| | - Ada K. Hagan
- University of Michigan Medical School, Department of Microbiology and Immunology. Ann Arbor, Michigan, United States of America
| | - Jessica L. Hastie
- Center for Biologics Evaluation and Research, US Food and Drug Administration. Silver Spring, Maryland, United States of America
| | - Nicole P. Giordano
- Center for Biologics Evaluation and Research, US Food and Drug Administration. Silver Spring, Maryland, United States of America
| | - Ashley D. Smith
- Center for Biologics Evaluation and Research, US Food and Drug Administration. Silver Spring, Maryland, United States of America
| | - Alyxandria M. Schubert
- Center for Biologics Evaluation and Research, US Food and Drug Administration. Silver Spring, Maryland, United States of America
| | - Paul E. Carlson
- Center for Biologics Evaluation and Research, US Food and Drug Administration. Silver Spring, Maryland, United States of America
| | - Philip C. Hanna
- University of Michigan Medical School, Department of Microbiology and Immunology. Ann Arbor, Michigan, United States of America
- * E-mail:
| |
Collapse
|
15
|
Spengler G, Kincses A, Gajdács M, Amaral L. New Roads Leading to Old Destinations: Efflux Pumps as Targets to Reverse Multidrug Resistance in Bacteria. Molecules 2017; 22:molecules22030468. [PMID: 28294992 PMCID: PMC6155429 DOI: 10.3390/molecules22030468] [Citation(s) in RCA: 118] [Impact Index Per Article: 16.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2017] [Revised: 03/09/2017] [Accepted: 03/10/2017] [Indexed: 01/05/2023] Open
Abstract
Multidrug resistance (MDR) has appeared in response to selective pressures resulting from the incorrect use of antibiotics and other antimicrobials. This inappropriate application and mismanagement of antibiotics have led to serious problems in the therapy of infectious diseases. Bacteria can develop resistance by various mechanisms and one of the most important factors resulting in MDR is efflux pump-mediated resistance. Because of the importance of the efflux-related multidrug resistance the development of new therapeutic approaches aiming to inhibit bacterial efflux pumps is a promising way to combat bacteria having over-expressed MDR efflux systems. The definition of an efflux pump inhibitor (EPI) includes the ability to render the bacterium increasingly more sensitive to a given antibiotic or even reverse the multidrug resistant phenotype. In the recent years numerous EPIs have been developed, although so far their clinical application has not yet been achieved due to their in vivo toxicity and side effects. In this review, we aim to give a short overview of efflux mediated resistance in bacteria, EPI compounds of plant and synthetic origin, and the possible methods to investigate and screen EPI compounds in bacterial systems.
Collapse
Affiliation(s)
- Gabriella Spengler
- Department of Medical Microbiology and Immunobiology, Faculty of Medicine, University of Szeged, 6720 Szeged, Hungary.
| | - Annamária Kincses
- Department of Medical Microbiology and Immunobiology, Faculty of Medicine, University of Szeged, 6720 Szeged, Hungary.
| | - Márió Gajdács
- Department of Medical Microbiology and Immunobiology, Faculty of Medicine, University of Szeged, 6720 Szeged, Hungary.
| | - Leonard Amaral
- Department of Medical Microbiology and Immunobiology, Faculty of Medicine, University of Szeged, 6720 Szeged, Hungary.
- Travel Medicine, Institute of Hygiene and Tropical Medicine, Universidade Nova de Lisboa, 1349-008 Lisbon, Portugal.
| |
Collapse
|
16
|
Amaral L, Viveiros M. Thioridazine: A Non-Antibiotic Drug Highly Effective, in Combination with First Line Anti-Tuberculosis Drugs, against Any Form of Antibiotic Resistance of Mycobacterium tuberculosis Due to Its Multi-Mechanisms of Action. Antibiotics (Basel) 2017; 6:antibiotics6010003. [PMID: 28098814 PMCID: PMC5372983 DOI: 10.3390/antibiotics6010003] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2016] [Revised: 12/29/2016] [Accepted: 01/05/2017] [Indexed: 01/01/2023] Open
Abstract
This review presents the evidence that supports the use of thioridazine (TZ) for the therapy of a pulmonary tuberculosis infection regardless of its antibiotic resistance status. The evidence consists of in vitro and ex vivo assays that demonstrate the activity of TZ against all encountered Mycobacterium tuberculosis (Mtb) regardless of its antibiotic resistance phenotype, as well as in vivo as a therapy for mice infected with multi-drug resistant strains of Mtb, or for human subjects infected with extensively drug resistant (XDR) Mtb. The mechanisms of action by which TZ brings about successful therapeutic outcomes are presented in detail.
Collapse
Affiliation(s)
- Leonard Amaral
- Insititute of Hygiene and Tropical Medicine, Universidade Nova de Lisboa, Lisbon 1349-008, Portugal.
- Institute of Medical Microbiology and Immunobiology, University of Szeged, Szeged 6720, Hungary.
| | - Miguel Viveiros
- Unidade de Microbiologia Médica, Global Health and Tropical Medicine, Instituto de Higiene e Medicina Tropical, Universidade Nova de Lisboa, Lisbon 1349-008, Portugal.
| |
Collapse
|
17
|
Pinto-Almeida A, Mendes T, Armada A, Belo S, Carrilho E, Viveiros M, Afonso A. The Role of Efflux Pumps in Schistosoma mansoni Praziquantel Resistant Phenotype. PLoS One 2015; 10:e0140147. [PMID: 26445012 PMCID: PMC4596880 DOI: 10.1371/journal.pone.0140147] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2015] [Accepted: 09/21/2015] [Indexed: 12/25/2022] Open
Abstract
BACKGROUND Schistosomiasis is a neglected disease caused by a trematode of the genus Schistosoma that is second only to malaria in public health significance in Africa, South America, and Asia. Praziquantel (PZQ) is the drug of choice to treat this disease due to its high cure rates and no significant side effects. However, in the last years increasingly cases of tolerance to PZQ have been reported, which has caused growing concerns regarding the emergency of resistance to this drug. METHODOLOGY/PRINCIPAL FINDINGS Here we describe the selection of a parasitic strain that has a stable resistance phenotype to PZQ. It has been reported that drug resistance in helminths might involve efflux pumps such as members of ATP-binding cassette transport proteins, including P-glycoprotein and multidrug resistance-associated protein families. Here we evaluate the role of efflux pumps in Schistosoma mansoni resistance to PZQ, by comparing the efflux pumps activity in susceptible and resistant strains. The evaluation of the efflux activity was performed by an ethidium bromide accumulation assay in presence and absence of Verapamil. The role of efflux pumps in resistance to PZQ was further investigated comparing the response of susceptible and resistant parasites in the absence and presence of different doses of Verapamil, in an ex vivo assay, and these results were further reinforced through the comparison of the expression levels of SmMDR2 RNA by RT-PCR. CONCLUSIONS/SIGNIFICANCE This work strongly suggests the involvement of Pgp-like transporters SMDR2 in Praziquantel drug resistance in S. mansoni. Low doses of Verapamil successfully reverted drug resistance. Our results might give an indication that a combination therapy with PZQ and natural or synthetic Pgp modulators can be an effective strategy for the treatment of confirmed cases of resistance to PZQ in S. mansoni.
Collapse
Affiliation(s)
- António Pinto-Almeida
- Graduate Program in Areas of Basic and Applied Biology, Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto, Porto, Portugal
- Medical Parasitology Unit, Global Health and Tropical Medicine, GHTM, Instituto de Higiene e Medicina Tropical, IHMT, Universidade Nova de Lisboa, UNL, Lisbon, Portugal
- Universidade de São Paulo, Instituto de Química de São Carlos, São Carlos, SP, Brazil
| | - Tiago Mendes
- Medical Parasitology Unit, Global Health and Tropical Medicine, GHTM, Instituto de Higiene e Medicina Tropical, IHMT, Universidade Nova de Lisboa, UNL, Lisbon, Portugal
- Institute of Biology, Universidade de Campinas, Campinas, SP, Brazil
| | - Ana Armada
- Medical Microbiology Unit, Global Health and Tropical Medicine, GHTM, Instituto de Higiene e Medicina Tropical, IHMT, Universidade Nova de Lisboa, UNL, Lisbon, Portugal
| | - Silvana Belo
- Medical Parasitology Unit, Global Health and Tropical Medicine, GHTM, Instituto de Higiene e Medicina Tropical, IHMT, Universidade Nova de Lisboa, UNL, Lisbon, Portugal
| | - Emanuel Carrilho
- Universidade de São Paulo, Instituto de Química de São Carlos, São Carlos, SP, Brazil
| | - Miguel Viveiros
- Medical Microbiology Unit, Global Health and Tropical Medicine, GHTM, Instituto de Higiene e Medicina Tropical, IHMT, Universidade Nova de Lisboa, UNL, Lisbon, Portugal
| | - Ana Afonso
- Medical Parasitology Unit, Global Health and Tropical Medicine, GHTM, Instituto de Higiene e Medicina Tropical, IHMT, Universidade Nova de Lisboa, UNL, Lisbon, Portugal
- Universidade de São Paulo, Instituto de Química de São Carlos, São Carlos, SP, Brazil
- Laboratory of Parasitology, Departamento de Morfologia e Patologia, Universidade Federal de São Carlos, São Carlos, SP, Brazil
| |
Collapse
|
18
|
Li XZ, Plésiat P, Nikaido H. The challenge of efflux-mediated antibiotic resistance in Gram-negative bacteria. Clin Microbiol Rev 2015; 28:337-418. [PMID: 25788514 PMCID: PMC4402952 DOI: 10.1128/cmr.00117-14] [Citation(s) in RCA: 924] [Impact Index Per Article: 102.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
The global emergence of multidrug-resistant Gram-negative bacteria is a growing threat to antibiotic therapy. The chromosomally encoded drug efflux mechanisms that are ubiquitous in these bacteria greatly contribute to antibiotic resistance and present a major challenge for antibiotic development. Multidrug pumps, particularly those represented by the clinically relevant AcrAB-TolC and Mex pumps of the resistance-nodulation-division (RND) superfamily, not only mediate intrinsic and acquired multidrug resistance (MDR) but also are involved in other functions, including the bacterial stress response and pathogenicity. Additionally, efflux pumps interact synergistically with other resistance mechanisms (e.g., with the outer membrane permeability barrier) to increase resistance levels. Since the discovery of RND pumps in the early 1990s, remarkable scientific and technological advances have allowed for an in-depth understanding of the structural and biochemical basis, substrate profiles, molecular regulation, and inhibition of MDR pumps. However, the development of clinically useful efflux pump inhibitors and/or new antibiotics that can bypass pump effects continues to be a challenge. Plasmid-borne efflux pump genes (including those for RND pumps) have increasingly been identified. This article highlights the recent progress obtained for organisms of clinical significance, together with methodological considerations for the characterization of MDR pumps.
Collapse
Affiliation(s)
- Xian-Zhi Li
- Human Safety Division, Veterinary Drugs Directorate, Health Products and Food Branch, Health Canada, Ottawa, Ontario, Canada
| | - Patrick Plésiat
- Laboratoire de Bactériologie, Faculté de Médecine-Pharmacie, Centre Hospitalier Régional Universitaire, Université de Franche-Comté, Besançon, France
| | - Hiroshi Nikaido
- Department of Molecular and Cell Biology, University of California, Berkeley, California, USA
| |
Collapse
|
19
|
Lavilla Lerma L, Benomar N, Valenzuela AS, Casado Muñoz MDC, Gálvez A, Abriouel H. Role of EfrAB efflux pump in biocide tolerance and antibiotic resistance of Enterococcus faecalis and Enterococcus faecium isolated from traditional fermented foods and the effect of EDTA as EfrAB inhibitor. Food Microbiol 2014; 44:249-57. [PMID: 25084670 DOI: 10.1016/j.fm.2014.06.009] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2014] [Revised: 05/15/2014] [Accepted: 06/11/2014] [Indexed: 11/30/2022]
Abstract
Enterococcus faecalis and Enterococcus faecium isolated from various traditional fermented foods of both animal and vegetable origins have shown multidrug resistance to several antibiotics and tolerance to biocides. Reduced susceptibility was intra and inter-species dependent and was due to specific and unspecific mechanisms such as efflux pumps. EfrAB, a heterodimeric ABC transporter efflux pump, was detected in 100% of multidrug resistant (MDR) E. faecalis strains and only in 12% of MDR E. faecium strains. EfrAB expression was induced by half of minimum inhibitory concentration (MIC) of gentamicin, streptomycin and chloramphenicol. However, expression of efrA and efrB genes was highly dependent on the strain tested and on the antimicrobial used. Our results indicated that 3 mM EDTA highly reduced the MICs of almost all drugs tested. Nevertheless, the higher reductions (>8 folds) were obtained with gentamicin, streptomycin, chlorhexidine and triclosan. Reductions of MICs were correlated with down-regulation of EfrAB expression (10-140 folds) in all three MDR enterococci strains. This is the first report describing the role of EfrAB in the efflux of antibiotics and biocides which reflect also the importance of EfrAB in multidrug resistance in enterococci. EDTA used at low concentration as food preservative could be one of the best choices to prevent spread of multidrug resistant enterococci throughout food chain by decreasing EfrAB expression. EfrAB could be an attractive target not only in enterococci present in food matrix but also those causing infections as well by using EDTA as therapeutic agent in combination with low doses of antibiotics.
Collapse
Affiliation(s)
- Leyre Lavilla Lerma
- Área de Microbiología, Departamento de Ciencias de la Salud, Facultad de Ciencias Experimentales, Universidad de Jaén, 23071 Jaén, Spain
| | - Nabil Benomar
- Área de Microbiología, Departamento de Ciencias de la Salud, Facultad de Ciencias Experimentales, Universidad de Jaén, 23071 Jaén, Spain
| | - Antonio Sánchez Valenzuela
- Área de Microbiología, Departamento de Ciencias de la Salud, Facultad de Ciencias Experimentales, Universidad de Jaén, 23071 Jaén, Spain
| | - María del Carmen Casado Muñoz
- Área de Microbiología, Departamento de Ciencias de la Salud, Facultad de Ciencias Experimentales, Universidad de Jaén, 23071 Jaén, Spain
| | - Antonio Gálvez
- Área de Microbiología, Departamento de Ciencias de la Salud, Facultad de Ciencias Experimentales, Universidad de Jaén, 23071 Jaén, Spain
| | - Hikmate Abriouel
- Área de Microbiología, Departamento de Ciencias de la Salud, Facultad de Ciencias Experimentales, Universidad de Jaén, 23071 Jaén, Spain.
| |
Collapse
|
20
|
Viveiros M, Martins M, Rodrigues L, Machado D, Couto I, Ainsa J, Amaral L. Inhibitors of mycobacterial efflux pumps as potential boosters for anti-tubercular drugs. Expert Rev Anti Infect Ther 2014; 10:983-98. [DOI: 10.1586/eri.12.89] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
|
21
|
Amaral L, Martins A, Spengler G, Molnar J. Efflux pumps of Gram-negative bacteria: what they do, how they do it, with what and how to deal with them. Front Pharmacol 2014; 4:168. [PMID: 24427138 PMCID: PMC3879458 DOI: 10.3389/fphar.2013.00168] [Citation(s) in RCA: 82] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2013] [Accepted: 12/16/2013] [Indexed: 11/20/2022] Open
Abstract
This review discusses the relationship of the efflux pump (EP) system of Gram-negative bacteria to other antibiotic resistance mechanisms of the bacterium such as quorum sensing, biofilms, two component regulons, etc. The genetic responses of a Gram-negative to an antibiotic that render it immune to an antibiotic are also discussed. Lastly, the methods that have been developed for the identification of bacteria that over-express their EP system are presented in detail. Phenothiazines are well-known antipsychotic drugs with reported activity against bacterial EPs and other ancillary antibiotic mechanisms of the organism. Therefore these compounds will also be discussed.
Collapse
Affiliation(s)
- Leonard Amaral
- Travel Medicine of the Centro de Malária e Doenças Tropicais, Institute of Hygiene and Tropical Medicine, Universidade Nova de Lisboa Lisbon, Portugal ; Institute of Medical Microbiology and Immunobiology, University of Szeged Szeged, Hungary
| | - Ana Martins
- Institute of Medical Microbiology and Immunobiology, University of Szeged Szeged, Hungary ; Unit of Parasitology and Medical Microbiology, Institute of Hygiene and Tropical Medicine, Universidade Nova de Lisboa Lisbon, Portugal
| | - Gabriella Spengler
- Institute of Medical Microbiology and Immunobiology, University of Szeged Szeged, Hungary
| | - Joseph Molnar
- Institute of Medical Microbiology and Immunobiology, University of Szeged Szeged, Hungary
| |
Collapse
|
22
|
Valade E, Davin-Regli A, Bolla JM, Pagès JM. Bacterial Membrane, a Key for Controlling Drug Influx and Efflux. Antibiotics (Basel) 2013. [DOI: 10.1002/9783527659685.ch9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
|
23
|
Theodorou MC, Kyriakidis DA. Calcium channels blockers inhibit the signal transduction through the AtoSC system in Escherichia coli. Eur J Pharm Sci 2012; 47:84-96. [PMID: 22634222 DOI: 10.1016/j.ejps.2012.05.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2012] [Revised: 05/05/2012] [Accepted: 05/09/2012] [Indexed: 01/17/2023]
Abstract
Verapamil, diltiazem and nifedipine are Ca(2+)-channel blockers used in cardiovascular diseases. We report here that the Escherichia coli AtoSC signaling is inhibited by those blockers. AtoSC two-component system plays a pivotal role in sophisticated signaling networks in E. coli regulating processes implicated in bacterial homeostasis and pathogenicity. The Ca(2+)-channel blockers abrogated the in vitro full-length AtoS kinase autophosphorylation. However, they demonstrated no effect on the AtoS cytoplasmic form autophosphorylation. AtoC protected AtoS from verapamil or diltiazem but not from nifedipine, when the two constituents formed complex. The blockers did not affect the AtoS≈P to AtoC phosphotransfer. The blockers-mediated AtoSC inhibition was verified in vivo on the atoDAEB expression, which was inhibited only in AtoSC-expressing bacteria upon acetoacetate. The AtoS and AtoC protein or their genes transcription levels were unaffected by the blockers. Blockers demonstrated differential effects in the regulation of both the cytosolic- and most potently the membrane-bound-cPHB. Extracellular Ca(2+) counteracted the verapamil-mediated effect on cPHB only in atoSC(+) cells. Extracellular Ca(2+) reversed the diltiazem-mediated cPHB decreases in cells of both genetic backgrounds, yet a Ca(2+)-concentration dependent reversion was observed only in the AtoSC-regulated cPHB. Nifedipine caused a more pronounced cPHB down-regulation that was not reversed by extracellular Ca(2+). The AtoSC signaling inhibition by Ca(2+)-channel blockers used for human treatment, and their differential effects on cPHB-formed Ca(2+)-channels, signify their implications in bacterial-host interactions through the two-component signaling and could stimulate the design of Ca(2+)-channels blockers derivatives acting as inhibitors of two-component systems.
Collapse
Affiliation(s)
- Marina C Theodorou
- Laboratory of Biochemistry, Department of Chemistry, Aristotle University of Thessaloniki, GR-54124 Thessaloniki, Greece.
| | | |
Collapse
|
24
|
Why thioridazine in combination with antibiotics cures extensively drug-resistant Mycobacterium tuberculosis infections. Int J Antimicrob Agents 2012; 39:376-80. [PMID: 22445204 DOI: 10.1016/j.ijantimicag.2012.01.012] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2012] [Accepted: 01/18/2012] [Indexed: 11/22/2022]
Abstract
Thioridazine (TDZ) in combination with antibiotics to which extensively drug-resistant Mycobacterium tuberculosis (XDR-TB) is initially resistant yields a cure. This is due to the fact that TDZ enhances the killing of intracellular M. tuberculosis by non-killing macrophages, inhibits the genetic expression of efflux pumps of M. tuberculosis that extrude antibiotics prior to reaching their intended targets, and inhibits the activity of existing efflux pumps that contribute to the multidrug-resistant phenotype of M. tuberculosis. The combination of these effects of TDZ probably contributes to the successful recent cures of XDR-TB cases when the phenothiazine TDZ is used in combination with antibiotics to which the patient with XDR-TB was initially unresponsive.
Collapse
|
25
|
Genetic response of Salmonella enterica serotype Enteritidis to thioridazine rendering the organism resistant to the agent. Int J Antimicrob Agents 2012; 39:16-21. [DOI: 10.1016/j.ijantimicag.2011.08.013] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2011] [Revised: 08/19/2011] [Accepted: 08/24/2011] [Indexed: 01/29/2023]
|
26
|
Amaral L, Cerca P, Spengler G, Machado L, Martins A, Couto I, Viveiros M, Fanning S, Pagès JM. Ethidium bromide efflux by Salmonella: modulation by metabolic energy, pH, ions and phenothiazines. Int J Antimicrob Agents 2011; 38:140-5. [PMID: 21565465 DOI: 10.1016/j.ijantimicag.2011.03.014] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2011] [Revised: 03/21/2011] [Accepted: 03/22/2011] [Indexed: 11/16/2022]
Abstract
The main efflux pump of Salmonella enterica serotype Enteritidis, which obtains its energy for the extrusion of noxious agents from the proton-motive force, was studied with the aid of an ethidium bromide (EtBr) semi-automated method under conditions that define the role of metabolic energy, ions and pH in the extrusion of the universal substrate EtBr. The results obtained in this study indicate that in minimal medium containing sodium at pH 5 efflux of EtBr is independent of glucose, whereas at pH 8 metabolic energy is an absolute requirement for the maintenance of efflux. In deionised water at pH 5.5, metabolic energy is required for the maintenance of efflux. The inhibitory effect of the ionophore carbonyl cyanide m-chlorophenylhydrazone (CCCP) on efflux is shown to be minimised by low pH, and at high pH by metabolic energy. Similarly, thioridazine, an inhibitor of metabolic enzymes, inhibits efflux of EtBr only at pH 8 and the degree of inhibition is lessened by the presence of metabolic energy.
Collapse
Affiliation(s)
- Leonard Amaral
- Grupo de Micobactérias, Unidade de Microbiologia Médica, Instituto de Higiene e Medicina Tropical, Universidade Nova de Lisboa, Rua da Junqueira 100, 1349-008 Lisboa, Portugal.
| | | | | | | | | | | | | | | | | |
Collapse
|