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Alibert S, N'gompaza Diarra J, Hernandez J, Stutzmann A, Fouad M, Boyer G, Pagès JM. Multidrug efflux pumps and their role in antibiotic and antiseptic resistance: a pharmacodynamic perspective. Expert Opin Drug Metab Toxicol 2016; 13:301-309. [PMID: 27764576 DOI: 10.1080/17425255.2017.1251581] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
INTRODUCTION Worrying levels of bacterial resistance have been reported worldwide involving the failure of many available antibiotic treatments. Multidrug resistance (MDR) in Gram-negative bacteria is often ascribed to the presence of multiple and different resistance mechanisms in the same strain. RND efflux pumps play a major role and are an attractive target to discover new antibacterial drugs. Areas covered: This review discusses the prevalence of efflux pumps, their overexpression in clinical scenarios, their polyselectivity, their effect on the intracellular concentrations of various antibiotics associated with the alteration of the membrane permeability and their involvement in pathogenicity are discussed. Expert opinion: Efflux pumps are new targets for the development of adjuvant in antibiotic treatments by of efflux pump inhibition. They may allow us to rejuvenate old antibiotics acting on their concentration inside the bacteria and thus potentiating their activity while blocking the release of virulence factors. It is a pharmacodynamic challenge to finalize new combined therapy.
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Affiliation(s)
- Sandrine Alibert
- a Aix-Marseille Université, IRBA, TMCD2, UMR-MD1, Transporteurs Membranaires, Chimioresistance et Drug Design, Facultés de Médecine et de Pharmacie , Marseille , France
| | - Joannah N'gompaza Diarra
- a Aix-Marseille Université, IRBA, TMCD2, UMR-MD1, Transporteurs Membranaires, Chimioresistance et Drug Design, Facultés de Médecine et de Pharmacie , Marseille , France
| | - Jessica Hernandez
- a Aix-Marseille Université, IRBA, TMCD2, UMR-MD1, Transporteurs Membranaires, Chimioresistance et Drug Design, Facultés de Médecine et de Pharmacie , Marseille , France
| | - Aurélien Stutzmann
- a Aix-Marseille Université, IRBA, TMCD2, UMR-MD1, Transporteurs Membranaires, Chimioresistance et Drug Design, Facultés de Médecine et de Pharmacie , Marseille , France
| | - Marwa Fouad
- b Pharmaceutical Chemistry Department, Faculty of Pharmacy , Cairo University , Giza , Egypt
| | - Gérard Boyer
- a Aix-Marseille Université, IRBA, TMCD2, UMR-MD1, Transporteurs Membranaires, Chimioresistance et Drug Design, Facultés de Médecine et de Pharmacie , Marseille , France
| | - Jean-Marie Pagès
- a Aix-Marseille Université, IRBA, TMCD2, UMR-MD1, Transporteurs Membranaires, Chimioresistance et Drug Design, Facultés de Médecine et de Pharmacie , Marseille , France
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152
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Li Y, Cao S, Zhang L, Lau GW, Wen Y, Wu R, Zhao Q, Huang X, Yan Q, Huang Y, Wen X. A TolC-Like Protein of Actinobacillus pleuropneumoniae Is Involved in Antibiotic Resistance and Biofilm Formation. Front Microbiol 2016; 7:1618. [PMID: 27822201 PMCID: PMC5075564 DOI: 10.3389/fmicb.2016.01618] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2016] [Accepted: 09/28/2016] [Indexed: 11/13/2022] Open
Abstract
Actinobacillus pleuropneumoniae is the etiologic agent of porcine contagious pleuropneumonia, a significant disease that causes serious economic losses to the swine industry worldwide. Persistent infections caused by bacterial biofilms are recalcitrant to treat because of the particular drug resistance of biofilm-dwelling cells. TolC, a key component of multidrug efflux pumps, are responsible for multidrug resistance (MDR) in many Gram-negative bacteria. In this study, we identified two TolC-like proteins, TolC1 and TolC2, in A. pleuropneumoniae. Deletion of tolC1, but not tolC2, caused a significant reduction in biofilm formation, as well as increased drug sensitivity of both planktonic and biofilm cells. The genetic-complementation of the tolC1 mutation restored the competent biofilm and drug resistance. Besides, biofilm formation was inhibited and drug sensitivity was increased by the addition of phenylalanine-arginine beta-naphthylamide (PAβN), a well-known efflux pump inhibitor (EPI), suggesting a role for EPI in antibacterial strategies toward drug tolerance of A. pleuropneumoniae. Taken together, TolC1 is required for biofilm formation and is a part of the MDR machinery of both planktonic and biofilm cells, which could supplement therapeutic strategies for resistant bacteria and biofilm-related infections of A. pleuropneumoniae clinical isolate SC1516.
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Affiliation(s)
- Ying Li
- Research Center of Swine Diseases, College of Veterinary Medicine, Sichuan Agricultural University Chengdu, China
| | - Sanjie Cao
- Research Center of Swine Diseases, College of Veterinary Medicine, Sichuan Agricultural University Chengdu, China
| | - Luhua Zhang
- Research Center of Swine Diseases, College of Veterinary Medicine, Sichuan Agricultural UniversityChengdu, China; Department of Pathobiology, University of Illinois at Urbana-ChampaignUrbana, IL, USA
| | - Gee W Lau
- Department of Pathobiology, University of Illinois at Urbana-Champaign Urbana, IL, USA
| | - Yiping Wen
- Research Center of Swine Diseases, College of Veterinary Medicine, Sichuan Agricultural University Chengdu, China
| | - Rui Wu
- Research Center of Swine Diseases, College of Veterinary Medicine, Sichuan Agricultural University Chengdu, China
| | - Qin Zhao
- Research Center of Swine Diseases, College of Veterinary Medicine, Sichuan Agricultural University Chengdu, China
| | - Xiaobo Huang
- Research Center of Swine Diseases, College of Veterinary Medicine, Sichuan Agricultural University Chengdu, China
| | - Qigui Yan
- Research Center of Swine Diseases, College of Veterinary Medicine, Sichuan Agricultural University Chengdu, China
| | - Yong Huang
- Research Center of Swine Diseases, College of Veterinary Medicine, Sichuan Agricultural University Chengdu, China
| | - Xintian Wen
- Research Center of Swine Diseases, College of Veterinary Medicine, Sichuan Agricultural University Chengdu, China
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153
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Park KS, Choo H, Kim MK, Chong Y. Quercetin 7-O-Glutamate PotentiatesStaphylococcus aureusto Fluoroquinolone Antibiotics. B KOREAN CHEM SOC 2016. [DOI: 10.1002/bkcs.10901] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Kwang-Su Park
- Department of Integrative Bioscience and Biotechnology, Bio/Molecular Informatics Center; Konkuk University; Seoul 143-701 Korea
| | - Hyunah Choo
- Center for Neuro-Medicine; Korea Institute of Science and Technology; Seoul 02792 Korea
- Department of Biological Chemistry; University of Science and Technology; Daejeon 34113 Korea
| | - Mi Kyoung Kim
- Department of Integrative Bioscience and Biotechnology, Bio/Molecular Informatics Center; Konkuk University; Seoul 143-701 Korea
| | - Youhoon Chong
- Department of Integrative Bioscience and Biotechnology, Bio/Molecular Informatics Center; Konkuk University; Seoul 143-701 Korea
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154
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Goli HR, Nahaei MR, Rezaee MA, Hasani A, Samadi Kafil H, Aghazadeh M, Sheikhalizadeh V. Contribution of mexAB-oprM and mexXY (-oprA) efflux operons in antibiotic resistance of clinical Pseudomonas aeruginosa isolates in Tabriz, Iran. INFECTION GENETICS AND EVOLUTION 2016; 45:75-82. [PMID: 27562333 DOI: 10.1016/j.meegid.2016.08.022] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2015] [Revised: 08/20/2016] [Accepted: 08/20/2016] [Indexed: 10/21/2022]
Abstract
Overexpression of efflux pumps is one of the most important mechanisms that contributes to intrinsic and acquired resistance to antibiotics in Pseudomonas aeruginosa. The present study evaluated the role of MexAB-OprM and MexXY (-OprA) efflux pump overexpression in antibiotics resistance of P. aeruginosa clinical isolates. One-hundred clinical isolates of P. aeruginosa were obtained from four hospitals of Tabriz city in Northwest Iran. Isolates were identified and evaluated by the disk diffusion method and agar dilution in order to determine antibiotic resistance. Effect of Phenylalanine Arginine beta-Naphthylamide (PAβN) on susceptibility to various anti-Pseudomonas antimicrobials and expression levels of mexB and mexY using quantitative real-time PCR were determined in the clinical isolates. Random Amplified Polymorphic DNA Typing (RAPD-PCR) was used for genotyping of the isolates. The most and least effective antibiotics tested were colistin and ofloxacin, respectively. Seventy-one percent of the isolates were found as multidrug resistant (resistant to at least three different classes of antibiotics). Among ciprofloxacin and levofloxacin resistant isolates, 39.6% and 28.5% of them showed four-fold reduction in MIC with PAβN, respectively. Sixty-two percent and 65% of isolates overexpressed mexB and mexY, respectively. Sixty six isolates showed overexpression of both mexB and mexY efflux genes. Moreover, 76% and 88.7% of MDR isolates were mexB and mexY overexpressed, respectively. There were 30 different RAPD types in this study which were clustered into 6 clones. The study indicated that there is a significant correlation between the expression of efflux pumps and the resistance to most anti-pseudomonal antibiotics.
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Affiliation(s)
- Hamid Reza Goli
- Drug Applied Research Center, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Islamic Republic of Iran; Department of Medical Microbiology, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Islamic Republic of Iran; Student Research Committee, Tabriz University of Medical Sciences, Tabriz, Islamic Republic of Iran
| | - Mohammad Reza Nahaei
- Drug Applied Research Center, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Islamic Republic of Iran; Department of Medical Microbiology, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Islamic Republic of Iran
| | - Mohammad Ahangarzadeh Rezaee
- Infectious Diseases and Tropical Medicine Research Center, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Islamic Republic of Iran; Department of Medical Microbiology, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Islamic Republic of Iran
| | - Alka Hasani
- Infectious Diseases and Tropical Medicine Research Center, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Islamic Republic of Iran; Department of Medical Microbiology, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Islamic Republic of Iran
| | - Hossein Samadi Kafil
- Drug Applied Research Center, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Islamic Republic of Iran; Department of Medical Microbiology, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Islamic Republic of Iran
| | - Mohammad Aghazadeh
- Drug Applied Research Center, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Islamic Republic of Iran; Department of Medical Microbiology, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Islamic Republic of Iran.
| | - Vajihe Sheikhalizadeh
- Department of Medical Microbiology, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Islamic Republic of Iran
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155
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Morita Y, Nakashima KI, Nishino K, Kotani K, Tomida J, Inoue M, Kawamura Y. Berberine Is a Novel Type Efflux Inhibitor Which Attenuates the MexXY-Mediated Aminoglycoside Resistance in Pseudomonas aeruginosa. Front Microbiol 2016; 7:1223. [PMID: 27547203 PMCID: PMC4975076 DOI: 10.3389/fmicb.2016.01223] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2015] [Accepted: 07/22/2016] [Indexed: 01/10/2023] Open
Abstract
The emergence and spread of multidrug-resistant P. aeruginosa infections is of great concern, as very few agents are effective against strains of this species. Methanolic extracts from the Coptidis Rhizoma (the rhizomes of Coptis japonica var. major Satake) or Phellodendri Cortex (the bark of Phellodendron chinense Schneider) markedly reduced resistance to anti-pseudomonal aminoglycosides (e.g., amikacin) in multidrug-resistant P. aeruginosa strains. Berberine, the most abundant benzylisoquinoline alkaloid in the two extracts, reduced aminoglycoside resistance of P. aeruginosa via a mechanism that required the MexXY multidrug efflux system; berberine also reduced aminoglycoside MICs in Achromobacter xylosoxidans and Burkholderia cepacia, two species that harbor intrinsic multidrug efflux systems very similar to the MexXY. Furthermore this compound inhibited MexXY-dependent antibiotic resistance of other classes including cephalosporins (cefepime), macrolides (erythromycin), and lincosamides (lincomycin) demonstrated using a pseudomonad lacking the four other major Mex pumps. Although phenylalanine-arginine beta-naphthylamide (PAβN), a well-known efflux inhibitor, antagonized aminoglycoside in a MexXY-dependent manner, a lower concentration of berberine was sufficient to reduce amikacin resistance of P. aeruginosa in the presence of PAβN. Moreover, berberine enhanced the synergistic effects of amikacin and piperacillin (and vice versa) in multidrug-resistant P. aeruginosa strains. Thus, berberine appears to be a novel type inhibitor of the MexXY-dependent aminoglycoside efflux in P. aeruginosa. As aminoglycosides are molecules of choice to treat severe infections the clinical impact is potentially important.
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Affiliation(s)
- Yuji Morita
- Department of Microbiology, School of Pharmacy, Aichi Gakuin University Nagoya, Japan
| | - Ken-Ichi Nakashima
- Laboratory of Medicinal Resources, School of Pharmacy, Aichi Gakuin University Nagoya, Japan
| | - Kunihiko Nishino
- Department of Biomolecular Science and Regulation, Institute of Scientific and Industrial Research, Osaka University Osaka, Japan
| | - Kenta Kotani
- Department of Microbiology, School of Pharmacy, Aichi Gakuin University Nagoya, Japan
| | - Junko Tomida
- Department of Microbiology, School of Pharmacy, Aichi Gakuin University Nagoya, Japan
| | - Makoto Inoue
- Laboratory of Medicinal Resources, School of Pharmacy, Aichi Gakuin University Nagoya, Japan
| | - Yoshiaki Kawamura
- Department of Microbiology, School of Pharmacy, Aichi Gakuin University Nagoya, Japan
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156
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El-Shaer S, Shaaban M, Barwa R, Hassan R. Control of quorum sensing and virulence factors of Pseudomonas aeruginosa using phenylalanine arginyl β-naphthylamide. J Med Microbiol 2016; 65:1194-1204. [PMID: 27498852 DOI: 10.1099/jmm.0.000327] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The spread of multidrug-resistant Pseudomonas aeruginosa isolates constitutes a serious clinical challenge. Bacterial efflux machinery is a crucial mechanism of resistance among P. aeruginosa. Efflux inhibitors such as phenylalanine arginyl β-naphthylamide (PAβN) promote the bacterial susceptibility to antimicrobial agents. The pathogenesis of P. aeruginosa is coordinated via quorum sensing (QS). This study aims to find out the impact of efflux pump inhibitor, PAβN, on QS and virulence attributes in clinical isolates of P. aeruginosa. P. aeruginosa isolates were purified from urine and wound samples, and the antimicrobial susceptibility was carried out by disc diffusion method. The multidrug-resistant and the virulent isolates U16, U21, W19 and W23 were selected. PAβN enhanced their susceptibility to most antimicrobial agents. PAβN reduced QS signalling molecules N-3-oxo-dodecanoyl-l-homoserine lactone and N-butyryl-l-homoserine lactone without affecting bacterial viability. Moreover, PAβN eliminated their virulence factors such as elastase, protease, pyocyanin and bacterial motility. At the transcription level, PAβN significantly (P<0.01) diminished the relative expression of QS cascade (lasI, lasR, rhlI, rhlR, pqsA and pqsR) and QS regulated-type II secretory genes lasB (elastase) and toxA (exotoxin A) compared to the control untreated isolates U16 and U21. In addition, PAβN eliminated the relative expression of pelA (exopolysaccharides) in U16 and U21 isolates. Hence, P. aeruginosa-tested isolates became hypo-virulent upon using PAβN. PAβN significantly blocked the QS circuit and inhibited the virulence factors expressed by clinical isolates of P. aeruginosa. PAβN could be a prime substrate for development of QS inhibitors and prevention of P. aeruginosa pathogenicity.
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Affiliation(s)
- Soha El-Shaer
- Microbiology and Immunology Department, Faculty of Pharmacy, Mansoura University, 35516 Mansoura, Egypt
| | - Mona Shaaban
- Microbiology and Immunology Department, Faculty of Pharmacy, Mansoura University, 35516 Mansoura, Egypt
| | - Rasha Barwa
- Microbiology and Immunology Department, Faculty of Pharmacy, Mansoura University, 35516 Mansoura, Egypt
| | - Ramadan Hassan
- Microbiology and Immunology Department, Faculty of Pharmacy, Mansoura University, 35516 Mansoura, Egypt
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157
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Abstract
Resistance to antifungal drugs is an increasingly significant clinical problem. The most common antifungal resistance encountered is efflux pump-mediated resistance of Candida species to azole drugs. One approach to overcome this resistance is to inhibit the pumps and chemosensitize resistant strains to azole drugs. Drug discovery targeting fungal efflux pumps could thus result in the development of azole-enhancing combination therapy. Heterologous expression of fungal efflux pumps in Saccharomyces cerevisiae provides a versatile system for screening for pump inhibitors. Fungal efflux pumps transport a range of xenobiotics including fluorescent compounds. This enables the use of fluorescence-based detection, as well as growth inhibition assays, in screens to discover compounds targeting efflux-mediated antifungal drug resistance. A variety of medium- and high-throughput screens have been used to identify a number of chemical entities that inhibit fungal efflux pumps.
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158
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da Silva APS, Nascimento da Silva LC, Martins da Fonseca CS, de Araújo JM, Correia MTDS, Cavalcanti MDS, Lima VLDM. Antimicrobial Activity and Phytochemical Analysis of Organic Extracts from Cleome spinosa Jaqc. Front Microbiol 2016; 7:963. [PMID: 27446005 PMCID: PMC4924519 DOI: 10.3389/fmicb.2016.00963] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2015] [Accepted: 06/03/2016] [Indexed: 11/24/2022] Open
Abstract
Due to the use of Cleome spinosa Jacq. (Cleomaceae) in traditional medicine against inflammatory and infectious processes, this study evaluated the in vitro antimicrobial potential and phytochemical composition of extracts from its roots and leaves. From leaves (L) and roots (R) of C. spinosa different extracts were obtained (cyclohexane: ChL and ChR; chloroform: CL and CR; ethyl acetate: EAL and EAR, methanol: ML and MR). The antimicrobial activity was evaluated by the broth microdilution method to obtain the minimum inhibitory (MIC) and microbicidal (MMC) concentrations against 17 species, including bacteria and yeasts. Additionally, antimicrobial and combinatory effects with oxacillin were assessed against eight clinical isolates of Staphylococcus aureus. All C. spinosa extracts showed a broad spectrum of antimicrobial activity, as they have inhibited all tested bacteria and yeasts. This activity seems to be related to the phytochemicals (flavonoid, terpenoids and saponins) detected into the extracts of C. spinosa. ChL and CL extracts were the most actives, with MIC less than 1 mg/mL against S. aureus, Bacillus subtilis, and Micrococcus luteus. It is important to note that these concentrations are much lower than their 50% hemolysis concentration (HC50) values. Strong correlations were found between the average MIC against S. aureus and their phenolic (r = −0.89) and flavonoid content (r = −0.87), reinforcing the possible role of these metabolite classes on the antimicrobial activity of C. spinosa derived extracts. Moreover, CL and CR showed the best inhibitory activity against S. aureus clinical isolates, they also showed synergistic action with oxacillin against all these strains (at least at one combined proportion). These results encourage the identification of active substances which could be used as lead(s) molecules in the development of new antimicrobial drugs.
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Affiliation(s)
- Ana P Sant'Anna da Silva
- Departamento de Bioquímica, Centro de Ciências Biológicas, Universidade Federal de Pernambuco Recife, Brazil
| | | | - Caíque S Martins da Fonseca
- Departamento de Bioquímica, Centro de Ciências Biológicas, Universidade Federal de Pernambuco Recife, Brazil
| | - Janete M de Araújo
- Departamento de Antibióticos, Centro de Ciências Biológicas, Universidade Federal de Pernambuco Recife, Brazil
| | - Maria T Dos Santos Correia
- Departamento de Bioquímica, Centro de Ciências Biológicas, Universidade Federal de Pernambuco Recife, Pernambuco, Brazil
| | - Marilene da Silva Cavalcanti
- Departamento de Micologia, Centro de Ciências Biológicas, Universidade Federal de Pernambuco Recife, Pernambuco, Brazil
| | - Vera L de Menezes Lima
- Departamento de Bioquímica, Centro de Ciências Biológicas, Universidade Federal de Pernambuco Recife, Brazil
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159
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Evidence of a Substrate-Discriminating Entrance Channel in the Lower Porter Domain of the Multidrug Resistance Efflux Pump AcrB. Antimicrob Agents Chemother 2016; 60:4315-23. [PMID: 27161641 DOI: 10.1128/aac.00314-16] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2016] [Accepted: 05/01/2016] [Indexed: 11/20/2022] Open
Abstract
Efflux pumps of the resistance nodulation cell division (RND) transporter family, such as AcrB of Escherichia coli, play an important role in the development of multidrug resistance, but the molecular basis for their substrate promiscuity is not yet completely understood. From a collection of highly clarithromycin-resistant AcrB periplasmic domain mutants derived from in vitro random mutagenesis, we identified variants with an unusually altered drug resistance pattern characterized by increased susceptibility to many drugs of lower molecular weight, including fluoroquinolones, tetracyclines, and oxazolidinones, but unchanged or increased resistance to drugs of higher molecular weight, including macrolides. Sequencing of 14 such "divergent resistance" phenotype mutants and 15 control mutants showed that this unusual phenotype was associated with mutations at residues I38 and I671 predominantly to phenylalanine and threonine, respectively, both conferring a similar susceptibility pattern. Reconstructed I38F and I671T single mutants as well as an engineered I38F I671T double mutant with proved efflux competence revealed an equivalent phenotype with enhanced or unchanged resistance to many large AcrB substrates but increased susceptibility to several lower-molecular-weight drugs known to bind within the distal binding pocket. The two isoleucines located in close vicinity to each other in the lower porter domain of AcrB beneath the bottom of the proximal binding pocket may be part of a preferential small-drug entrance pathway that is compromised by the mutations. This finding supports recent indications of distinct entrance channels used by compounds with different physicochemical properties, of which molecular size appears to play a prominent role.
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160
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Abstract
DNA gyrase and topoisomerase IV are type IIA bacterial topoisomerases that are targeted by highly effective antibiotics. However, resistance via multiple mechanisms arises to limit the efficacies of these drugs. Continued research on type IIA bacterial topoisomerases has provided novel approaches to counter the most common resistance mechanism for utilization of these proven targets in antibacterial therapy. Bacterial topoisomerase I is being explored as an alternative target that is not expected to show cross-resistance. Dual targeting or combination therapy could be strategies for circumventing the development of resistance to topoisomerase-targeting antibiotics. Bacterial topoisomerases are high-value bactericidal targets that could continue to be exploited for antibacterial therapy, if new tactics to counter resistance can be adopted.
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161
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The analysis of the antibiotic resistome offers new opportunities for therapeutic intervention. Future Med Chem 2016; 8:1133-51. [DOI: 10.4155/fmc-2016-0027] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Most efforts in the development of antimicrobials have focused on the screening of lethal targets. Nevertheless, the constant expansion of antimicrobial resistance makes the antibiotic resistance determinants themselves suitable targets for finding inhibitors to be used in combination with antibiotics. Among them, inhibitors of antibiotic inactivating enzymes and of multidrug efflux pumps are suitable candidates for improving the efficacy of antibiotics. In addition, the application of systems biology tools is helping to understand the changes in bacterial physiology associated to the acquisition of resistance, including the increased susceptibility to other antibiotics displayed by some antibiotic-resistant mutants. This information is useful for implementing novel strategies based in metabolic interventions or combination of antibiotics for improving the efficacy of antibacterial therapy.
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162
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Pseudomonas aeruginosa: targeting cell-wall metabolism for new antibacterial discovery and development. Future Med Chem 2016; 8:975-92. [PMID: 27228070 DOI: 10.4155/fmc-2016-0017] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Pseudomonas aeruginosa is a leading cause of hospital-acquired infections and is resistant to most antibiotics. With therapeutic options against P. aeruginosa dwindling, and the lack of new antibiotics in advanced developmental stages, strategies for preserving the effectiveness of current antibiotics are urgently required. β-Lactam antibiotics are important agents for treating P. aeruginosa infections, thus, adjuvants that potentiate the activity of these compounds are desirable for extending their lifespan while new antibiotics - or antibiotic classes - are discovered and developed. In this review, we discuss recent research that has identified exploitable targets of cell-wall metabolism for the design and development of compounds that hinder resistance and potentiate the activity of antipseudomonal β-lactams.
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163
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Otręebska-Machaj E, Chevalier J, Handzlik J, Szymańska E, Schabikowski J, Boyer G, Bolla JM, Kieć-Kononowicz K, Pagès JM, Alibert S. Efflux Pump Blockers in Gram-Negative Bacteria: The New Generation of Hydantoin Based-Modulators to Improve Antibiotic Activity. Front Microbiol 2016; 7:622. [PMID: 27199950 PMCID: PMC4853399 DOI: 10.3389/fmicb.2016.00622] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2016] [Accepted: 04/15/2016] [Indexed: 01/21/2023] Open
Abstract
Multidrug resistant (MDR) bacteria are an increasing health problem with the shortage of new active antibiotic agents. Among effective mechanisms that contribute to the spread of MDR Gram-negative bacteria are drug efflux pumps that expel clinically important antibiotic classes out of the cell. Drug pumps are attractive targets to restore the susceptibility toward the expelled antibiotics by impairing their efflux activity. Arylhydantoin derivatives were investigated for their potentiation of activities of selected antibiotics described as efflux substrates in Enterobacter aerogenes expressing or not AcrAB pump. Several compounds increased the bacterial susceptibility toward nalidixic acid, chloramphenicol and sparfloxacin and were further pharmacomodulated to obtain a better activity against the AcrAB producing bacteria.
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Affiliation(s)
- Ewa Otręebska-Machaj
- Department of Technology and Biotechnology of Drugs, Medical College, Jagiellonian UniversityKrakow, Poland; UMR-MD1, Aix Marseille Université/IRBA, Facultés de Médecine et de PharmacieMarseille, France
| | - Jacqueline Chevalier
- UMR-MD1, Aix Marseille Université/IRBA, Facultés de Médecine et de Pharmacie Marseille, France
| | - Jadwiga Handzlik
- Department of Technology and Biotechnology of Drugs, Medical College, Jagiellonian University Krakow, Poland
| | - Ewa Szymańska
- Department of Technology and Biotechnology of Drugs, Medical College, Jagiellonian University Krakow, Poland
| | - Jakub Schabikowski
- Department of Technology and Biotechnology of Drugs, Medical College, Jagiellonian University Krakow, Poland
| | - Gérard Boyer
- UMR-MD1, Aix Marseille Université/IRBA, Facultés de Médecine et de Pharmacie Marseille, France
| | - Jean-Michel Bolla
- UMR-MD1, Aix Marseille Université/IRBA, Facultés de Médecine et de Pharmacie Marseille, France
| | - Katarzyna Kieć-Kononowicz
- Department of Technology and Biotechnology of Drugs, Medical College, Jagiellonian University Krakow, Poland
| | - Jean-Marie Pagès
- UMR-MD1, Aix Marseille Université/IRBA, Facultés de Médecine et de Pharmacie Marseille, France
| | - Sandrine Alibert
- UMR-MD1, Aix Marseille Université/IRBA, Facultés de Médecine et de Pharmacie Marseille, France
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164
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Cheng G, Dai M, Ahmed S, Hao H, Wang X, Yuan Z. Antimicrobial Drugs in Fighting against Antimicrobial Resistance. Front Microbiol 2016; 7:470. [PMID: 27092125 PMCID: PMC4824775 DOI: 10.3389/fmicb.2016.00470] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Accepted: 03/21/2016] [Indexed: 01/18/2023] Open
Abstract
The outbreak of antimicrobial resistance, together with the lack of newly developed antimicrobial drugs, represents an alarming signal for both human and animal healthcare worldwide. Selection of rational dosage regimens for traditional antimicrobial drugs based on pharmacokinetic/pharmacodynamic principles as well as development of novel antimicrobials targeting new bacterial targets or resistance mechanisms are key approaches in tackling AMR. In addition to the cellular level resistance (i.e., mutation and horizontal gene transfer of resistance determinants), the community level resistance (i.e., bilofilms and persisters) is also an issue causing antimicrobial therapy difficulties. Therefore, anti-resistance and antibiofilm strategies have currently become research hotspot to combat antimicrobial resistance. Although metallic nanoparticles can both kill bacteria and inhibit biofilm formation, the toxicity is still a big challenge for their clinical applications. In conclusion, rational use of the existing antimicrobials and combinational use of new strategies fighting against antimicrobial resistance are powerful warranties to preserve potent antimicrobial drugs for both humans and animals.
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Affiliation(s)
- Guyue Cheng
- Ministry of Agriculture Laboratory for Risk Assessment of Quality and Safety of Livestock and Poultry Products, Huazhong Agricultural University Wuhan, China
| | - Menghong Dai
- Ministry of Agriculture Laboratory for Risk Assessment of Quality and Safety of Livestock and Poultry Products, Huazhong Agricultural University Wuhan, China
| | - Saeed Ahmed
- National Reference Laboratory of Veterinary Drug Residues (HZAU) and Ministry of Agriculture Key Laboratory for the Detection of Veterinary Drug Residues in Foods, Huazhong Agricultural University Wuhan, China
| | - Haihong Hao
- Ministry of Agriculture Laboratory for Risk Assessment of Quality and Safety of Livestock and Poultry Products, Huazhong Agricultural University Wuhan, China
| | - Xu Wang
- Ministry of Agriculture Laboratory for Risk Assessment of Quality and Safety of Livestock and Poultry Products, Huazhong Agricultural University Wuhan, China
| | - Zonghui Yuan
- Ministry of Agriculture Laboratory for Risk Assessment of Quality and Safety of Livestock and Poultry Products, Huazhong Agricultural UniversityWuhan, China; National Reference Laboratory of Veterinary Drug Residues (HZAU) and Ministry of Agriculture Key Laboratory for the Detection of Veterinary Drug Residues in Foods, Huazhong Agricultural UniversityWuhan, China
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165
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Molecular basis for inhibition of AcrB multidrug efflux pump by novel and powerful pyranopyridine derivatives. Proc Natl Acad Sci U S A 2016; 113:3509-14. [PMID: 26976576 DOI: 10.1073/pnas.1602472113] [Citation(s) in RCA: 149] [Impact Index Per Article: 18.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
The Escherichia coli AcrAB-TolC efflux pump is the archetype of the resistance nodulation cell division (RND) exporters from Gram-negative bacteria. Overexpression of RND-type efflux pumps is a major factor in multidrug resistance (MDR), which makes these pumps important antibacterial drug discovery targets. We have recently developed novel pyranopyridine-based inhibitors of AcrB, which are orders of magnitude more powerful than the previously known inhibitors. However, further development of such inhibitors has been hindered by the lack of structural information for rational drug design. Although only the soluble, periplasmic part of AcrB binds and exports the ligands, the presence of the membrane-embedded domain in AcrB and its polyspecific binding behavior have made cocrystallization with drugs challenging. To overcome this obstacle, we have engineered and produced a soluble version of AcrB [AcrB periplasmic domain (AcrBper)], which is highly congruent in structure with the periplasmic part of the full-length protein, and is capable of binding substrates and potent inhibitors. Here, we describe the molecular basis for pyranopyridine-based inhibition of AcrB using a combination of cellular, X-ray crystallographic, and molecular dynamics (MD) simulations studies. The pyranopyridines bind within a phenylalanine-rich cage that branches from the deep binding pocket of AcrB, where they form extensive hydrophobic interactions. Moreover, the increasing potency of improved inhibitors correlates with the formation of a delicate protein- and water-mediated hydrogen bond network. These detailed insights provide a molecular platform for the development of novel combinational therapies using efflux pump inhibitors for combating multidrug resistant Gram-negative pathogens.
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166
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Zuo Z, Weng J, Wang W. Insights into the Inhibitory Mechanism of D13-9001 to the Multidrug Transporter AcrB through Molecular Dynamics Simulations. J Phys Chem B 2016; 120:2145-54. [PMID: 26900716 DOI: 10.1021/acs.jpcb.5b11942] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The resistance-nodulation-cell division transporter AcrB is responsible for energy transduction and substrate recognition in the tripartite AcrAB-TolC efflux system in Escherichia coli. Despite a broad substrate specificity, only a few compounds have been cocrystallized with AcrB inside the distal binding pocket (DBP), including doxorubicin (DOX) and D13-9001. D13-9001 is a promising efflux pump inhibitor that potentiates the efficacy of a wide variety of antibiotics. To understand its inhibition effect under the framework of functional rotating mechanism, we performed targeted and steered molecular dynamics simulations to compare the binding and extrusion processes of this inhibitor and the substrate DOX in AcrB. The results demonstrate that, with respect to DOX, the interaction of D13-9001 with the hydrophobic trap results in delayed disassociation from the DBP. Notably, the detachment of D13-9001 is tightly correlated with the side-chain reorientation of Phe628 and large-scale displacement of Tyr327. Furthermore, the inhibitor induces much more significant conformational changes at the exit gate than DOX does, thereby causing higher energy cost for extrusion and contributing to the inhibitory effect in addition to the tight binding at DBP.
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Affiliation(s)
- Zhicheng Zuo
- Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Department of Chemistry, and Institutes of Biomedical Sciences, Fudan University , Shanghai 200433, People's Republic of China
| | - Jingwei Weng
- Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Department of Chemistry, and Institutes of Biomedical Sciences, Fudan University , Shanghai 200433, People's Republic of China
| | - Wenning Wang
- Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Department of Chemistry, and Institutes of Biomedical Sciences, Fudan University , Shanghai 200433, People's Republic of China
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167
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Wang XY, Zhou L, Yang J, Ji GH, He YW. The RpfB-Dependent Quorum Sensing Signal Turnover System Is Required for Adaptation and Virulence in Rice Bacterial Blight Pathogen Xanthomonas oryzae pv. oryzae. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2016; 29:220-30. [PMID: 26667598 DOI: 10.1094/mpmi-09-15-0206-r] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Xanthomonas oryzae pv. oryzae, the bacterial blight pathogen of rice, produces diffusible signal factor (DSF) family quorum sensing signals to regulate virulence. The biosynthesis and perception of DSF family signals require components of the rpf (regulation of pathogenicity factors) cluster. In this study, we report that RpfB plays an essential role in DSF family signal turnover in X. oryzae pv. oryzae PXO99A. The production of DSF family signals was boosted by deletion of the rpfB gene and was abolished by its overexpression. The RpfC/RpfG-mediated DSF signaling system negatively regulates rpfB expression via the global transcription regulator Clp, whose activity is reversible in the presence of cyclic diguanylate monophosphate. These findings indicate that the DSF family signal turnover system in PXO99A is generally consistent with that in Xanthomonas campestris pv. campestris. Moreover, this study has revealed several specific roles of RpfB in PXO99A. First, the rpfB deletion mutant produced high levels of DSF family signals but reduced extracellular polysaccharide production, extracellular amylase activity, and attenuated pathogenicity. Second, the rpfB/rpfC double-deletion mutant was partially deficient in xanthomonadin production. Taken together, the RpfB-dependent DSF family signal turnover system is a conserved and naturally presenting signal turnover system in Xanthomonas spp., which plays unique roles in X. oryzae pv. oryzae adaptation and pathogenesis.
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Affiliation(s)
- Xing-Yu Wang
- 1 State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Lian Zhou
- 1 State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Jun Yang
- 2 College of Plant Protection, Yunnan Agricultural University, Kunming 650201, China
| | - Guang-Hai Ji
- 2 College of Plant Protection, Yunnan Agricultural University, Kunming 650201, China
| | - Ya-Wen He
- 1 State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, 200240, China
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168
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Wagner S, Sommer R, Hinsberger S, Lu C, Hartmann RW, Empting M, Titz A. Novel Strategies for the Treatment of Pseudomonas aeruginosa Infections. J Med Chem 2016; 59:5929-69. [DOI: 10.1021/acs.jmedchem.5b01698] [Citation(s) in RCA: 176] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Stefanie Wagner
- Chemical
Biology of Carbohydrates, Helmholtz Institute for Pharmaceutical Research Saarland (HIPS), D-66123 Saarbrücken, Germany
- Deutsches Zentrum für Infektionsforschung (DZIF), 30625 Standort Hannover-Braunschweig, Germany
| | - Roman Sommer
- Chemical
Biology of Carbohydrates, Helmholtz Institute for Pharmaceutical Research Saarland (HIPS), D-66123 Saarbrücken, Germany
- Deutsches Zentrum für Infektionsforschung (DZIF), 30625 Standort Hannover-Braunschweig, Germany
| | - Stefan Hinsberger
- Deutsches Zentrum für Infektionsforschung (DZIF), 30625 Standort Hannover-Braunschweig, Germany
- Drug
Design and Optimization, Helmholtz Institute for Pharmaceutical Research Saarland (HIPS), D-66123 Saarbrücken, Germany
| | - Cenbin Lu
- Deutsches Zentrum für Infektionsforschung (DZIF), 30625 Standort Hannover-Braunschweig, Germany
- Drug
Design and Optimization, Helmholtz Institute for Pharmaceutical Research Saarland (HIPS), D-66123 Saarbrücken, Germany
| | - Rolf W. Hartmann
- Deutsches Zentrum für Infektionsforschung (DZIF), 30625 Standort Hannover-Braunschweig, Germany
- Drug
Design and Optimization, Helmholtz Institute for Pharmaceutical Research Saarland (HIPS), D-66123 Saarbrücken, Germany
| | - Martin Empting
- Deutsches Zentrum für Infektionsforschung (DZIF), 30625 Standort Hannover-Braunschweig, Germany
- Drug
Design and Optimization, Helmholtz Institute for Pharmaceutical Research Saarland (HIPS), D-66123 Saarbrücken, Germany
| | - Alexander Titz
- Chemical
Biology of Carbohydrates, Helmholtz Institute for Pharmaceutical Research Saarland (HIPS), D-66123 Saarbrücken, Germany
- Deutsches Zentrum für Infektionsforschung (DZIF), 30625 Standort Hannover-Braunschweig, Germany
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169
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An overview of bacterial efflux pumps and computational approaches to study efflux pump inhibitors. Future Med Chem 2016; 8:195-210. [DOI: 10.4155/fmc.15.173] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Micro-organisms express a wide range of transmembrane pumps known as multidrug efflux pumps that improve the micro-organism's ability to survive in severe environments and contribute to resistance against antibiotic and antimicrobial agents. There is significant interest in developing efflux inhibitors as an adjunct to treatment with current and next generation of antibiotics. A greater understanding of drug recognition and transport by multidrug efflux pumps is needed to develop clinically useful inhibitors, given the breadth of molecules that can be effluxed by these systems. We summarize some structural and functional data that could provide insights into the inhibition of transport mechanisms of these intricate molecular nanomachines with a focus on the advances in computational approaches.
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170
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Loughman K, Hall J, Knowlton S, Sindeldecker D, Gilson T, Schmitt DM, Birch JWM, Gajtka T, Kobe BN, Florjanczyk A, Ingram J, Bakshi CS, Horzempa J. Temperature-Dependent Gentamicin Resistance of Francisella tularensis is Mediated by Uptake Modulation. Front Microbiol 2016; 7:37. [PMID: 26858709 PMCID: PMC4729955 DOI: 10.3389/fmicb.2016.00037] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2015] [Accepted: 01/11/2016] [Indexed: 11/13/2022] Open
Abstract
Gentamicin (Gm) is an aminoglycoside commonly used to treat bacterial infections such as tularemia – the disease caused by Francisella tularensis. In addition to being pathogenic, F. tularensis is found in environmental niches such as soil where this bacterium likely encounters Gm producers (Micromonospora sp.). Here we show that F. tularensis exhibits increased resistance to Gm at ambient temperature (26°C) compared to mammalian body temperature (37°C). To evaluate whether F. tularensis was less permeable to Gm at 26°C, a fluorescent marker [Texas Red (Tr)] was conjugated with Gm, yielding Tr-Gm. Bacteria incubated at 26°C showed reduced fluorescence compared to those at 37°C when exposed to Tr-Gm suggesting that uptake of Gm was reduced at 26°C. Unconjugated Gm competitively inhibited uptake of Tr-Gm, demonstrating that this fluorescent compound was taken up similarly to unconjugated Gm. Lysates of F. tularensis bacteria incubated with Gm at 37°C inhibited the growth of Escherichia coli significantly more than lysates from bacteria incubated at 26°C, further indicating reduced uptake at this lower temperature. Other facultative pathogens (Listeria monocytogenes and Klebsiella pneumoniae) exhibited increased resistance to Gm at 26°C suggesting that the results generated using F. tularensis may be generalizable to diverse bacteria. Regulation of the uptake of antibiotics provides a mechanism by which facultative pathogens survive alongside antibiotic-producing microbes in nature.
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Affiliation(s)
- Kathleen Loughman
- Department of Natural Sciences and Mathematics, West Liberty University West Liberty, WV, USA
| | - Jesse Hall
- Department of Natural Sciences and Mathematics, West Liberty University West Liberty, WV, USA
| | - Samantha Knowlton
- Department of Natural Sciences and Mathematics, West Liberty University West Liberty, WV, USA
| | - Devin Sindeldecker
- Department of Natural Sciences and Mathematics, West Liberty University West Liberty, WV, USA
| | - Tricia Gilson
- Department of Natural Sciences and Mathematics, West Liberty University West Liberty, WV, USA
| | - Deanna M Schmitt
- Department of Natural Sciences and Mathematics, West Liberty University West Liberty, WV, USA
| | - James W-M Birch
- Department of Natural Sciences and Mathematics, West Liberty University West Liberty, WV, USA
| | - Tara Gajtka
- Department of Natural Sciences and Mathematics, West Liberty University West Liberty, WV, USA
| | - Brianna N Kobe
- Department of Natural Sciences and Mathematics, West Liberty University West Liberty, WV, USA
| | - Aleksandr Florjanczyk
- Department of Natural Sciences and Mathematics, West Liberty University West Liberty, WV, USA
| | - Jenna Ingram
- Department of Natural Sciences and Mathematics, West Liberty University West Liberty, WV, USA
| | - Chandra S Bakshi
- Department of Microbiology and Immunology, New York Medical College Valhalla, NY, USA
| | - Joseph Horzempa
- Department of Natural Sciences and Mathematics, West Liberty University West Liberty, WV, USA
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171
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Klahn P, Brönstrup M. New Structural Templates for Clinically Validated and Novel Targets in Antimicrobial Drug Research and Development. Curr Top Microbiol Immunol 2016; 398:365-417. [PMID: 27704270 DOI: 10.1007/82_2016_501] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The development of bacterial resistance against current antibiotic drugs necessitates a continuous renewal of the arsenal of efficacious drugs. This imperative has not been met by the output of antibiotic research and development of the past decades for various reasons, including the declining efforts of large pharma companies in this area. Moreover, the majority of novel antibiotics are chemical derivatives of existing structures that represent mostly step innovations, implying that the available chemical space may be exhausted. This review negates this impression by showcasing recent achievements in lead finding and optimization of antibiotics that have novel or unexplored chemical structures. Not surprisingly, many of the novel structural templates like teixobactins, lysocin, griselimycin, or the albicidin/cystobactamid pair were discovered from natural sources. Additional compounds were obtained from the screening of synthetic libraries and chemical synthesis, including the gyrase-inhibiting NTBI's and spiropyrimidinetrione, the tarocin and targocil inhibitors of wall teichoic acid synthesis, or the boronates and diazabicyclo[3.2.1]octane as novel β-lactamase inhibitors. A motif that is common to most clinically validated antibiotics is that they address hotspots in complex biosynthetic machineries, whose functioning is essential for the bacterial cell. Therefore, an introduction to the biological targets-cell wall synthesis, topoisomerases, the DNA sliding clamp, and membrane-bound electron transport-is given for each of the leads presented here.
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Affiliation(s)
- Philipp Klahn
- Department of Chemical Biology, Helmholtz Centre for Infection Research, Inhoffenstrasse 7, 38124, Braunschweig, Germany.
| | - Mark Brönstrup
- Department of Chemical Biology, Helmholtz Centre for Infection Research, Inhoffenstrasse 7, 38124, Braunschweig, Germany.
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172
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El Zowalaty ME, Al Thani AA, Webster TJ, El Zowalaty AE, Schweizer HP, Nasrallah GK, Marei HE, Ashour HM. Pseudomonas aeruginosa: arsenal of resistance mechanisms, decades of changing resistance profiles, and future antimicrobial therapies. Future Microbiol 2015; 10:1683-706. [PMID: 26439366 DOI: 10.2217/fmb.15.48] [Citation(s) in RCA: 88] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Antimicrobial resistance is one of the most serious public health issues facing humans since the discovery of antimicrobial agents. The frequent, prolonged, and uncontrolled use of antimicrobial agents are major factors in the emergence of antimicrobial-resistant bacterial strains, including multidrug-resistant variants. Pseudomonas aeruginosa is a leading cause of nosocomial infections. The abundant data on the increased resistance to antipseudomonal agents support the need for global action. There is a paucity of new classes of antibiotics active against P. aeruginosa. Here, we discuss recent antibacterial resistance profiles and mechanisms of resistance by P. aeruginosa. We also review future potential methods for controlling antibiotic-resistant bacteria, such as phage therapy, nanotechnology and antipseudomonal vaccines.
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Affiliation(s)
- Mohamed E El Zowalaty
- Department of Microbiology & Immunology, Emory University School of Medicine, Atlanta, GA 30322, USA.,BioMedical Research Center, Qatar University, Doha, PO Box 2713, Qatar
| | - Asmaa A Al Thani
- BioMedical Research Center, Qatar University, Doha, PO Box 2713, Qatar.,Department of Health Sciences, College of Arts and Sciences, Qatar University, Doha 2713, Qatar
| | - Thomas J Webster
- Department of Chemical Engineering, Northeastern University, Boston, MA 02018, USA.,Center of Excellence for Advanced Materials Research, King Abdulaziz University, Jeddah, Kingdom of Saudi Arabia
| | - Ahmed E El Zowalaty
- Department of Physiology & Pharmacology, College of Veterinary Medicine, University of Georgia, Athens, GA 30602, USA.,Interdisciplinary Toxicology Program, University of Georgia, Athens, GA 30602, USA
| | - Herbert P Schweizer
- Department of Molecular Genetics & Microbiology, College of Medicine, University of Florida, Gainesville, FL 32611, USA.,Emerging Pathogens Institute, Institute for Therapeutic Innovation, University of Florida Gainesville, FL 32611, USA
| | - Gheyath K Nasrallah
- BioMedical Research Center, Qatar University, Doha, PO Box 2713, Qatar.,Department of Health Sciences, College of Arts and Sciences, Qatar University, Doha 2713, Qatar
| | - Hany E Marei
- BioMedical Research Center, Qatar University, Doha, PO Box 2713, Qatar
| | - Hossam M Ashour
- Department of Microbiology & Immunology, Faculty of Pharmacy, Cairo University, Egypt.,Department of Pharmacy Practice, Eugene Applebaum College of Pharmacy & Health Sciences, Wayne State University, Detroit, MI, USA
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173
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Zgurskaya HI, López CA, Gnanakaran S. Permeability Barrier of Gram-Negative Cell Envelopes and Approaches To Bypass It. ACS Infect Dis 2015; 1:512-522. [PMID: 26925460 DOI: 10.1021/acsinfecdis.5b00097] [Citation(s) in RCA: 377] [Impact Index Per Article: 41.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Gram-negative bacteria are intrinsically resistant to many antibiotics. Species that have acquired multidrug resistance and cause infections that are effectively untreatable present a serious threat to public health. The problem is broadly recognized and tackled at both the fundamental and applied levels. This paper summarizes current advances in understanding the molecular bases of the low permeability barrier of Gram-negative pathogens, which is the major obstacle in discovery and development of antibiotics effective against such pathogens. Gaps in knowledge and specific strategies to break this barrier and to achieve potent activities against difficult Gram-negative bacteria are also discussed.
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Affiliation(s)
- Helen I. Zgurskaya
- Department of Chemistry and Biochemistry, University of Oklahoma, 101 Stephenson Parkway, Norman, Oklahoma 73019, United States
| | - Cesar A. López
- Theoretical Biology and Biophysics Group, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - S. Gnanakaran
- Theoretical Biology and Biophysics Group, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
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174
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Garneau-Tsodikova S, Labby KJ. Mechanisms of Resistance to Aminoglycoside Antibiotics: Overview and Perspectives. MEDCHEMCOMM 2015; 7:11-27. [PMID: 26877861 DOI: 10.1039/c5md00344j] [Citation(s) in RCA: 272] [Impact Index Per Article: 30.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Aminoglycoside (AG) antibiotics are used to treat many Gram-negative and some Gram-positive infections and, importantly, multidrug-resistant tuberculosis. Among various bacterial species, resistance to AGs arises through a variety of intrinsic and acquired mechanisms. The bacterial cell wall serves as a natural barrier for small molecules such as AGs and may be further fortified via acquired mutations. Efflux pumps work to expel AGs from bacterial cells, and modifications here too may cause further resistance to AGs. Mutations in the ribosomal target of AGs, while rare, also contribute to resistance. Of growing clinical prominence is resistance caused by ribosome methyltransferases. By far the most widespread mechanism of resistance to AGs is the inactivation of these antibiotics by AG-modifying enzymes. We provide here an overview of these mechanisms by which bacteria become resistant to AGs and discuss their prevalence and potential for clinical relevance.
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Affiliation(s)
- Sylvie Garneau-Tsodikova
- University of Kentucky, Department of Pharmaceutical Sciences, 789 South Limestone Street, Lexington, KY, USA. ; Tel: 859-218-1686
| | - Kristin J Labby
- Beloit College, Department of Chemistry, 700 College Street, Beloit, WI, USA. ; Tel: 608-363-2273
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175
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Juhas M. Pseudomonas aeruginosa essentials: an update on investigation of essential genes. MICROBIOLOGY-SGM 2015; 161:2053-60. [PMID: 26311069 DOI: 10.1099/mic.0.000161] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Pseudomonas aeruginosa is the leading cause of nosocomial infections, particularly in immunocompromised, cancer, burn and cystic fibrosis patients. Development of novel antimicrobials against P. aeruginosa is therefore of the highest importance. Although the first reports on P. aeruginosa essential genes date back to the early 2000s, a number of more sensitive genomic approaches have been used recently to better define essential genes in this organism. These analyses highlight the evolution of the definition of an 'essential' gene from the traditional to the context-dependent. Essential genes, particularly those indispensable under the clinically relevant conditions, are considered to be promising targets of novel antibiotics against P. aeruginosa. This review provides an update on the investigation of P. aeruginosa essential genes. Special focus is on recently identified P. aeruginosa essential genes and their exploitation for the development of antimicrobials.
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Affiliation(s)
- Mario Juhas
- Department of Pathology, University of Cambridge, Tennis Court Road, Cambridge CB2 1QP, UK
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