1
|
Kaur M, Mingeot-Leclercq MP. Maintenance of bacterial outer membrane lipid asymmetry: insight into MlaA. BMC Microbiol 2024; 24:186. [PMID: 38802775 PMCID: PMC11131202 DOI: 10.1186/s12866-023-03138-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Accepted: 11/29/2023] [Indexed: 05/29/2024] Open
Abstract
The outer membrane (OM) of Gram-negative bacteria acts as an effective barrier to protect against toxic compounds. By nature, the OM is asymmetric with the highly packed lipopolysaccharide (LPS) at the outer leaflet and glycerophospholipids at the inner leaflet. OM asymmetry is maintained by the Mla system, in which is responsible for the retrograde transport of glycerophospholipids from the OM to the inner membrane. This system is comprised of six Mla proteins, including MlaA, an OM lipoprotein involved in the removal of glycerophospholipids that are mis-localized at the outer leaflet of the OM. Interestingly, MlaA was initially identified - and called VacJ - based on its role in the intracellular spreading of Shigella flexneri.Many open questions remain with respect to the Mla system and the mechanism involved in the translocation of mislocated glycerophospholipids at the outer leaflet of the OM, by MlaA. After summarizing the current knowledge on MlaA, we focus on the impact of mlaA deletion on OM lipid composition and biophysical properties of the OM. How changes in OM lipid composition and biophysical properties can impact the generation of membrane vesicles and membrane permeability is discussed. Finally, we explore whether and how MlaA might be a candidate for improving the activity of antibiotics and as a vaccine candidate.Efforts dedicated to understanding the relationship between the OM lipid composition and the mechanical strength of the bacterial envelope and, in turn, how such properties act against external stress, are needed for the design of new targets or drugs for Gram-negative infections.
Collapse
Affiliation(s)
- M Kaur
- Louvain Drug Research Institute, Université catholique de Louvain, Unité de Pharmacologie cellulaire et moléculaire, B1.73.05; 73 Av E. Mounier, Brussels, 1200, Belgium
| | - M-P Mingeot-Leclercq
- Louvain Drug Research Institute, Université catholique de Louvain, Unité de Pharmacologie cellulaire et moléculaire, B1.73.05; 73 Av E. Mounier, Brussels, 1200, Belgium.
| |
Collapse
|
2
|
Morici P, Rizzato C, Ghelardi E, Rossolini GM, Lupetti A. Sensitization of KPC and NDM Klebsiella pneumoniae To Rifampicin by the Human Lactoferrin-Derived Peptide hLF1-11. Microbiol Spectr 2023; 11:e0276722. [PMID: 36537823 PMCID: PMC9927577 DOI: 10.1128/spectrum.02767-22] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
A synergistic effect of non-bactericidal concentrations of the human lactoferrin (hLF)-derived peptide hLF1-11 and rifampicin against multidrug-resistant KPC (Klebsiella pneumoniae carbapenemase)-producing K. pneumoniae has been previously shown. The present study focuses on the mechanism(s) underlying this synergistic effect. The contribution of hLF1-11 and rifampicin to the synergistic effect was evaluated by killing assays with KPC K. pneumoniae cells incubated with hLF1-11 and, after washing, with rifampicin, or vice versa. Cell membrane permeability and polarization upon exposure to hLF1-11 and/or rifampicin were evaluated by ethidium bromide (EtBr) and DiBAC4(3) (bis-1,3-dibutylbarbituric acid trimethine oxonol) permeability, respectively. The effect of carbonyl cyanide m-chlorophenyl hydrazone (CCCP), an uncoupler of oxidative phosphorylation, was also evaluated. KPC K. pneumoniae cells were effectively killed after prior exposure to rifampicin for 30 to 60 min followed by treatment with hLF1-11, while no antibacterial activity was observed when cells were incubated with hLF1-11 first and then with rifampicin. EtBr accumulation increased upon exposure to hLF1-11 or the combination of hLF1-11 and rifampicin, but not upon exposure to rifampicin alone. Moreover, hLF1-11 induced a dose-dependent membrane depolarization. As expected, the antibacterial activity of hLF1-11 alone or combined with rifampicin was significantly reduced in the presence of CCCP. Furthermore, hLF1-11 and rifampicin were synergistic also against a colistin-resistant NDM (New Delhi metallo-β-lactamase)-producing K. pneumoniae strain. The results suggest that rifampicin was accumulated by KPC cells during the 30-to-60-min incubation and that the addition of hLF1-11 sensitized bacterial cells to rifampicin by inducing a transient loss of membrane potential and increased cell membrane permeability, thus facilitating the entrance and retention of rifampicin into the cytoplasm. IMPORTANCE The present study describes a synergistic effect between rifampicin, an impermeable hydrophobic antibiotic with an intracellular target, and an hLF1-11, an antimicrobial peptide derived from human lactoferrin, against multidrug-resistant Klebsiella pneumoniae. Carbapenem-resistant K. pneumoniae has recently caused an outbreak in Tuscany, Italy, thus pressing the need for the development of new treatment options. The mechanisms underlying such a synergistic effect have been studied. The results suggest that the synergistic effect was due to the transient loss of membrane potential induced by hLF1-11 and the subsequent increase in cell membrane permeability which allowed rifampicin to enter the bacterial cell. Therefore, it is likely that a sub-inhibitory concentration of hLF1-11 can efficiently permeabilize K. pneumoniae cells to rifampicin, allowing the antibiotic to reach its intracellular target. These results encourage further exploration of possible applications of this synergistic combination in the treatment of K. pneumoniae infections.
Collapse
Affiliation(s)
- Paola Morici
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Pisa, Italy
| | - Cosmeri Rizzato
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Pisa, Italy
| | - Emilia Ghelardi
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Pisa, Italy
| | - Gian Maria Rossolini
- Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy
- Clinical Microbiology and Virology Unit, Florence Careggi University Hospital, Florence, Italy
| | - Antonella Lupetti
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Pisa, Italy
| |
Collapse
|
3
|
Emergence of coexistence of a novel bla NDM-5-harbouring IncI1-I plasmid and an mcr-1.1-harbouring IncHI2 plasmid in a clinical Escherichia coli isolate in China. J Infect Public Health 2022; 15:1363-1369. [PMID: 36334462 DOI: 10.1016/j.jiph.2022.10.020] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Revised: 10/18/2022] [Accepted: 10/23/2022] [Indexed: 11/06/2022] Open
Abstract
BACKGROUND Co-harbouring of carbapenem and colistin resistance genes in multidrug-resistant Enterobacterales strains poses a serious public health problem. In this study, an MCR-1.1 and NDM-5 coproducing Escherichia coli strain named EC6563 was isolated and characterized. OBJECTIVES This study aimed to characterize a clinical carbapenem-resistant E. coli isolate which co-harbours mcr-1.1 and blaNDM-5 on separate plasmids, and explored the phenotypic and genotypic characteristics of the mcr-1.1- and blaNDM-5-harbouring plasmids. METHODS E. coli isolate EC6563 was subjected to antimicrobial susceptibility testing, conjugation assay, stability of the plasmid and growth rate determination. In addition, the whole genome sequence of this strain was obtained and the genetic characteristics of the mcr-1.1- and blaNDM-5-harbouring plasmids were analyzed. RESULTS Carbapenem-resistant E. coli isolate EC6563 was resistant to all the tested antibiotics except tigecycline. Bioinformatic analysis confirmed that the IncHI2 plasmid carrying mcr-1.1 was highly similar to the previously reported mcr-1.1-harbouring plasmid pGDP37-4, and carried multiple drug resistance genes and the IncI1-I plasmid carrying blaNDM-5 had low similarity to the published blaNDM-5-carrying IncI1-I plasmid pEC-16-10-NDM-5. The pEC6563-NDM5 plasmid was capable of conjugation with an efficiency of 1.34 × 10-2 in a filter mating experiment. The transconjugant J53/pEC6563-NDM5 was able to be stably inherited after 12 days of passage. CONCLUSIONS To the best of our knowledge, this is the first time that an IncHI2 plasmid carrying mcr-1.1 and an IncI1-I plasmid carrying blaNDM-5 is found to coexist in an E. coli isolate. Our research expands the known diversity of plasmids in NDM-5-producing Enterobacterales strains. Meanwhile, effective measures should be taken to prevent the spread of these plasmids.
Collapse
|
4
|
Shi Y, Wareham DW, Yuan Y, Deng X, Mata A, Azevedo HS. Polymyxin B-Triggered Assembly of Peptide Hydrogels for Localized and Sustained Release of Combined Antimicrobial Therapy. Adv Healthc Mater 2021; 10:e2101465. [PMID: 34523266 DOI: 10.1002/adhm.202101465] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2021] [Revised: 08/24/2021] [Indexed: 12/30/2022]
Abstract
Repurposing old antibiotics into more effective and safer formulations is an emergent approach to tackle the growing threat of antimicrobial resistance. Herein, a peptide hydrogel is reported for the localized and sustained release of polymyxin B (PMB), a decade-old antibiotic with increasing clinical utility for treating multidrug-resistant Gram-negative bacterial infections. The hydrogel is assembled by additing PMB solution into a rationally designed peptide amphiphile (PA) solution and its mechanical properties can be adjusted through the addition of counterions, envisioning its application in diverse infection scenarios. Sustained release of PMB from the hydrogel over a 5-day period and prolonged antimicrobial activities against Gram-negative bacteria are observed. The localized release of active PMB from the hydrogel is shown to be effective in vivo for treating Pseudomonas aeruginosa infection in the Galleria mellonella burn wound infection model, dramatically reducing the mortality from 93% to 13%. Complementary antimicrobial activity against Gram-positive Staphylococcus aureus and enhanced antimicrobial effect against the Gram-negative Acinetobacter baumannii are observed when an additional antibiotic fusidic acid is incorporated into the hydrogen network. These results demonstrate the potential of the PMB-triggered PA hydrogel as a versatile platform for the localized and sustained delivery of combined antimicrobial therapies.
Collapse
Affiliation(s)
- Yejiao Shi
- School of Engineering and Materials Science Queen Mary University of London London E1 4NS UK
- Institute of Bioengineering Queen Mary University of London London E1 4NS UK
| | - David W. Wareham
- Center for Immunobiology The Blizard Institute Barts and The London School of Medicine and Dentistry Queen Mary University of London London E1 2AT UK
- Barts Health NHS Trust London E1 2AT UK
| | - Yichen Yuan
- School of Engineering and Materials Science Queen Mary University of London London E1 4NS UK
- Institute of Bioengineering Queen Mary University of London London E1 4NS UK
| | - Xinru Deng
- School of Engineering and Materials Science Queen Mary University of London London E1 4NS UK
- Institute of Bioengineering Queen Mary University of London London E1 4NS UK
| | - Alvaro Mata
- School of Pharmacy University of Nottingham Nottingham NG7 2RD UK
- Department of Chemical and Environmental Engineering University of Nottingham Nottingham NG7 2AT UK
- Biodiscovery Institute University of Nottingham Nottingham NG7 2RD UK
| | - Helena S. Azevedo
- School of Engineering and Materials Science Queen Mary University of London London E1 4NS UK
- Institute of Bioengineering Queen Mary University of London London E1 4NS UK
| |
Collapse
|
5
|
Lan X, Guo Q, Liu Z, Liu K, He J, Li R, Sun H, Yao W, Wang L. Facile preparation of nanomicelles using polymyxin E for enhanced antitumor effects. JOURNAL OF BIOMATERIALS SCIENCE-POLYMER EDITION 2021; 33:329-341. [PMID: 34606738 DOI: 10.1080/09205063.2021.1989568] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Chemotherapy is a major cancer treatment that uses antitumor drugs to kill fast-growing cancer cells. Many kinds of drug carriers have been developed to deliver and achieve controlled release of small-molecule therapeutic agents. However, many therapeutic agent carriers need complex preparation process. The natural polypeptides may serve as proper drug carriers. More specifically, polymyxin E (PE) is a kind of natural antibiotic lipopeptides. It is commonly used to treat infections caused by multidrug-resistant Gram-negative bacteria. Herein, we present a facile method to prepare DOX-loaded polymyxin E micelles (PE-DOX micelles) to enhance the therapeutic effect of anticancer drug doxorubicin (DOX). The hydrodynamic sizes and zeta potential of the prepared nanomedicine (PE-DOX micelles) were 142.0 nm and 6.47 mV, respectively. The release of DOX from PE-DOX micelles was faster at pH 5.5 than that at pH 7.4. Furthermore, PE exhibited negligible cytotoxicity to A549 cells and HeLa cells within 50 μg/mL, while PE-DOX micelles caused higher cytotoxicity than that of free DOX. Moreover, the intravenously injected PE-DOX micelles showed good biocompatibility and obvious antitumor effect after 14 days' treatment in vivo. The PE-DOX micelles have great potential to be used as anticancer agent in the future.
Collapse
Affiliation(s)
- Xifa Lan
- First Hospital of Qinhuangdao, Qinhuangdao, China
| | - Quanling Guo
- Key Laboratory of Applied Chemistry, College of Environmental and Chemical Engineering, Yanshan University, Qinhuangdao, China
| | - Zhiwei Liu
- Key Laboratory of Applied Chemistry, College of Environmental and Chemical Engineering, Yanshan University, Qinhuangdao, China
| | - Kai Liu
- Key Laboratory of Applied Chemistry, College of Environmental and Chemical Engineering, Yanshan University, Qinhuangdao, China
| | - Jinfeng He
- Key Laboratory of Applied Chemistry, College of Environmental and Chemical Engineering, Yanshan University, Qinhuangdao, China
| | - Ruyu Li
- Key Laboratory of Applied Chemistry, College of Environmental and Chemical Engineering, Yanshan University, Qinhuangdao, China
| | | | - Wenxiu Yao
- First Hospital of Qinhuangdao, Qinhuangdao, China
| | - Longgang Wang
- Key Laboratory of Applied Chemistry, College of Environmental and Chemical Engineering, Yanshan University, Qinhuangdao, China
| |
Collapse
|
6
|
Alabresm A, Chandler SL, Benicewicz BC, Decho AW. Nanotargeting of Resistant Infections with a Special Emphasis on the Biofilm Landscape. Bioconjug Chem 2021; 32:1411-1430. [PMID: 34319073 PMCID: PMC8527872 DOI: 10.1021/acs.bioconjchem.1c00116] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Bacterial resistance to antimicrobial compounds is a growing concern in medical and public health circles. Overcoming the adaptable and duplicative resistance mechanisms of bacteria requires chemistry-based approaches. Engineered nanoparticles (NPs) now offer unique advantages toward this effort. However, most in situ infections (in humans) occur as attached biofilms enveloped in a protective surrounding matrix of extracellular polymers, where survival of microbial cells is enhanced. This presents special considerations in the design and deployment of antimicrobials. Here, we review recent efforts to combat resistant bacterial strains using NPs and, then, explore how NP surfaces may be specifically engineered to enhance the potency and delivery of antimicrobial compounds. Special NP-engineering challenges in the design of NPs must be overcome to penetrate the inherent protective barriers of the biofilm and to successfully deliver antimicrobials to bacterial cells. Future challenges are discussed in the development of new antibiotics and their mechanisms of action and targeted delivery via NPs.
Collapse
Affiliation(s)
- Amjed Alabresm
- Department of Environmental Health Sciences, University of South Carolina, Columbia, South Carolina 29208, United States
- Department of Biological Development of Shatt Al-Arab & N. Arabian Gulf, Marine Science Centre, University of Basrah, Basrah, Iraq
| | - Savannah L Chandler
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina 29208, United States
| | - Brian C Benicewicz
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina 29208, United States
- USC NanoCenter, University of South Carolina, Columbia, South Carolina 29208, United States
| | - Alan W Decho
- Department of Environmental Health Sciences, University of South Carolina, Columbia, South Carolina 29208, United States
| |
Collapse
|
7
|
Lu CH, Shiau CW, Chang YC, Kung HN, Wu JC, Lim CH, Yeo HH, Chang HC, Chien HS, Huang SH, Hung WK, Wei JR, Chiu HC. SC5005 dissipates the membrane potential to kill Staphylococcus aureus persisters without detectable resistance. J Antimicrob Chemother 2021; 76:2049-2056. [PMID: 33855344 DOI: 10.1093/jac/dkab114] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Accepted: 03/13/2021] [Indexed: 01/01/2023] Open
Abstract
OBJECTIVES In the past few decades, multiple-antibiotic-resistant Staphylococcus aureus has emerged and quickly spread in hospitals and communities worldwide. Additionally, the formation of antibiotic-tolerant persisters and biofilms further reduces treatment efficacy. Previously, we identified a sorafenib derivative, SC5005, with bactericidal activity against MRSA in vitro and in vivo. Here, we sought to elucidate the resistance status, mode of action and anti-persister activity of this compound. METHODS The propensity of S. aureus to develop SC5005 resistance was evaluated by assessment of spontaneous resistance and by multi-passage selection. The mode of action of SC5005 was investigated using macromolecular synthesis, LIVE/DEAD and ATPlite assays and DiOC2(3) staining. The effect of SC5005 on the mammalian cytoplasmic membrane was measured using haemolytic and lactate dehydrogenase (LDH) assays and flow cytometry. RESULTS SC5005 depolarized and permeabilized the bacterial cytoplasmic membrane, leading to reduced ATP production. Because of this mode of action, no resistance of S. aureus to SC5005 was observed after constant exposure to sub-lethal concentrations for 200 passages. The membrane-perturbing activity of SC5005 was specific to bacteria, as no significant haemolysis or release of LDH from human HT-29 cells was detected. Additionally, compared with other bactericidal antibiotics, SC5005 exhibited superior activity in eradicating both planktonic and biofilm-embedded S. aureus persisters. CONCLUSIONS Because of its low propensity for resistance development and potent persister-eradicating activity, SC5005 is a promising lead compound for developing new therapies for biofilm-related infections caused by S. aureus.
Collapse
Affiliation(s)
- Chieh-Hsien Lu
- Department of Clinical Laboratory Sciences and Medical Biotechnology, College of Medicine, National Taiwan University, Taipei 10048, Taiwan
| | - Chung-Wai Shiau
- Institute of Biopharmaceutical Sciences, National Yang-Ming University, Taipei 11221, Taiwan
| | - Yung-Chi Chang
- Graduate Institute of Microbiology, College of Medicine, National Taiwan University, Taipei 10051, Taiwan
| | - Hsiu-Ni Kung
- Graduate Institute of Anatomy and Cell Biology, College of Medicine, National Taiwan University, Taipei 10051, Taiwan
| | - Jui-Ching Wu
- Department of Clinical Laboratory Sciences and Medical Biotechnology, College of Medicine, National Taiwan University, Taipei 10048, Taiwan.,Department of Laboratory Medicine, National Taiwan University Hospital, College of Medicine, National Taiwan University, Taipei 10021, Taiwan
| | - Chui-Hian Lim
- Department of Clinical Laboratory Sciences and Medical Biotechnology, College of Medicine, National Taiwan University, Taipei 10048, Taiwan
| | - Hui-Hui Yeo
- Department of Clinical Laboratory Sciences and Medical Biotechnology, College of Medicine, National Taiwan University, Taipei 10048, Taiwan
| | - Han-Chu Chang
- Department of Clinical Laboratory Sciences and Medical Biotechnology, College of Medicine, National Taiwan University, Taipei 10048, Taiwan
| | - Han-Sheng Chien
- Department of Clinical Laboratory Sciences and Medical Biotechnology, College of Medicine, National Taiwan University, Taipei 10048, Taiwan
| | - Sheng-Hsuan Huang
- Department of Clinical Laboratory Sciences and Medical Biotechnology, College of Medicine, National Taiwan University, Taipei 10048, Taiwan.,Department of Laboratory Medicine, National Taiwan University Hospital, College of Medicine, National Taiwan University, Taipei 10021, Taiwan
| | - Wei-Kang Hung
- Department of Clinical Laboratory Sciences and Medical Biotechnology, College of Medicine, National Taiwan University, Taipei 10048, Taiwan
| | - Jun-Rong Wei
- Department of Immunology and Infectious Diseases, Harvard T.H. Chan School of Public Health, Boston, MA, 02115, USA
| | - Hao-Chieh Chiu
- Department of Clinical Laboratory Sciences and Medical Biotechnology, College of Medicine, National Taiwan University, Taipei 10048, Taiwan.,Department of Laboratory Medicine, National Taiwan University Hospital, College of Medicine, National Taiwan University, Taipei 10021, Taiwan
| |
Collapse
|
8
|
Chen SP, Chen EHL, Yang SY, Kuo PS, Jan HM, Yang TC, Hsieh MY, Lee KT, Lin CH, Chen RPY. A Systematic Study of the Stability, Safety, and Efficacy of the de novo Designed Antimicrobial Peptide PepD2 and Its Modified Derivatives Against Acinetobacter baumannii. Front Microbiol 2021; 12:678330. [PMID: 34220763 PMCID: PMC8250858 DOI: 10.3389/fmicb.2021.678330] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Accepted: 05/27/2021] [Indexed: 12/12/2022] Open
Abstract
Searching for new antimicrobials is a pressing issue to conquer the emergence of multidrug-resistant (MDR) bacteria and fungi. Antimicrobial peptides (AMPs) usually have antimicrobial mechanisms different from those of traditional antibiotics and bring new hope in the discovery of new antimicrobials. In addition to antimicrobial activity, stability and target selectivity are important concerns to decide whether an antimicrobial peptide can be applied in vivo. Here, we used a simple de novo designed peptide, pepD2, which contains only three kinds of amino acid residues (W, K, L), as an example to evaluate how the residues and modifications affect the antimicrobial activity against Acinetobacter baumannii, stability in plasma, and toxicity to human HEK293 cells. We found that pepI2 with a Leu→Ile substitution can decrease the minimum bactericidal concentrations (MBC) against A. baumannii by one half (4 μg/mL). A D-form peptide, pepdD2, in which the D-enantiomers replaced the L-enantiomers of the Lys(K) and Leu(L) residues, extended the peptide half-life in plasma by more than 12-fold. PepD3 is 3-residue shorter than pepD2. Decreasing peptide length did not affect antimicrobial activity but increased the IC50 to HEK293 cells, thus increased the selectivity index (SI) between A. baumannii and HEK293 cells from 4.7 to 8.5. The chain length increase of the N-terminal acyl group and the Lys→Arg substitution greatly enhanced the hemolytic activity, hence those modifications are not good for clinical application. Unlike colistin, the action mechanism of our peptides relies on negatively charged lipids rather than lipopolysaccharides. Therefore, not only gram-negative bacteria but also gram-positive bacteria can be killed by our peptides.
Collapse
Affiliation(s)
- Sung-Pang Chen
- Institute of Biological Chemistry, Academia Sinica, Taipei, Taiwan.,Institute of Biochemical Sciences, National Taiwan University, Taipei, Taiwan
| | - Eric H-L Chen
- Institute of Biological Chemistry, Academia Sinica, Taipei, Taiwan
| | - Sheng-Yung Yang
- Institute of Biological Chemistry, Academia Sinica, Taipei, Taiwan
| | - Pin-Shin Kuo
- Institute of Biological Chemistry, Academia Sinica, Taipei, Taiwan.,Institute of Biochemical Sciences, National Taiwan University, Taipei, Taiwan
| | - Hau-Ming Jan
- Institute of Biological Chemistry, Academia Sinica, Taipei, Taiwan
| | - Tsai-Chen Yang
- Institute of Biological Chemistry, Academia Sinica, Taipei, Taiwan
| | - Ming-Yen Hsieh
- Institute of Biological Chemistry, Academia Sinica, Taipei, Taiwan
| | - Kung-Ta Lee
- Department of Biochemical Science and Technology, National Taiwan University, Taipei, Taiwan
| | - Chun-Hung Lin
- Institute of Biological Chemistry, Academia Sinica, Taipei, Taiwan.,Institute of Biochemical Sciences, National Taiwan University, Taipei, Taiwan
| | - Rita P-Y Chen
- Institute of Biological Chemistry, Academia Sinica, Taipei, Taiwan.,Institute of Biochemical Sciences, National Taiwan University, Taipei, Taiwan
| |
Collapse
|
9
|
Investigating the action of the microalgal pigment marennine on Vibrio splendidus by in vivo 2H and 31P solid-state NMR. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2021; 1863:183642. [PMID: 34000261 DOI: 10.1016/j.bbamem.2021.183642] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 02/02/2021] [Revised: 04/28/2021] [Accepted: 05/04/2021] [Indexed: 11/21/2022]
Abstract
This work investigates the potential probiotic effect of marennine - a natural pigment produced by the diatom Haslea ostrearia - on Vibrio splendidus. These marine bacteria are often considered a threat for aquaculture; therefore, chemical antibiotics can be required to reduce bacterial outbreaks. In vivo2H solid-state NMR was used to probe the effects of marennine on the bacterial membrane in the exponential and stationary phases. Comparisons were made with polymyxin B (PxB) - an antibiotic used in aquaculture and known to interact with Gram(-) bacteria membranes. We also investigated the effect of marennine using 31P solid-state NMR on model membranes. Our results show that marennine has little effect on phospholipid headgroups dynamics, but reduces the acyl chain fluidity. Our data suggest that the two antimicrobial agents perturb V. splendidus membranes through different mechanisms. While PxB would alter the bacterial outer and inner membranes, marennine would act through a membrane stiffening mechanism, without affecting the bilayer integrity. Our study proposes this microalgal pigment, which is harmless for humans, as a potential treatment against vibriosis.
Collapse
|
10
|
Rybenkov VV, Zgurskaya HI, Ganguly C, Leus IV, Zhang Z, Moniruzzaman M. The Whole Is Bigger than the Sum of Its Parts: Drug Transport in the Context of Two Membranes with Active Efflux. Chem Rev 2021; 121:5597-5631. [PMID: 33596653 PMCID: PMC8369882 DOI: 10.1021/acs.chemrev.0c01137] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Cell envelope plays a dual role in the life of bacteria by simultaneously protecting it from a hostile environment and facilitating access to beneficial molecules. At the heart of this ability lie the restrictive properties of the cellular membrane augmented by efflux transporters, which preclude intracellular penetration of most molecules except with the help of specialized uptake mediators. Recently, kinetic properties of the cell envelope came into focus driven on one hand by the urgent need in new antibiotics and, on the other hand, by experimental and theoretical advances in studies of transmembrane transport. A notable result from these studies is the development of a kinetic formalism that integrates the Michaelis-Menten behavior of individual transporters with transmembrane diffusion and offers a quantitative basis for the analysis of intracellular penetration of bioactive compounds. This review surveys key experimental and computational approaches to the investigation of transport by individual translocators and in whole cells, summarizes key findings from these studies and outlines implications for antibiotic discovery. Special emphasis is placed on Gram-negative bacteria, whose envelope contains two separate membranes. This feature sets these organisms apart from Gram-positive bacteria and eukaryotic cells by providing them with full benefits of the synergy between slow transmembrane diffusion and active efflux.
Collapse
Affiliation(s)
- Valentin V Rybenkov
- Department of Chemistry and Biochemistry, Stephenson Life Sciences Research Center, University of Oklahoma, 101 Stephenson Parkway, Norman, Oklahoma 73019, United States
| | - Helen I Zgurskaya
- Department of Chemistry and Biochemistry, Stephenson Life Sciences Research Center, University of Oklahoma, 101 Stephenson Parkway, Norman, Oklahoma 73019, United States
| | - Chhandosee Ganguly
- Department of Chemistry and Biochemistry, Stephenson Life Sciences Research Center, University of Oklahoma, 101 Stephenson Parkway, Norman, Oklahoma 73019, United States
| | - Inga V Leus
- Department of Chemistry and Biochemistry, Stephenson Life Sciences Research Center, University of Oklahoma, 101 Stephenson Parkway, Norman, Oklahoma 73019, United States
| | - Zhen Zhang
- Department of Chemistry and Biochemistry, Stephenson Life Sciences Research Center, University of Oklahoma, 101 Stephenson Parkway, Norman, Oklahoma 73019, United States
| | - Mohammad Moniruzzaman
- Department of Chemistry and Biochemistry, Stephenson Life Sciences Research Center, University of Oklahoma, 101 Stephenson Parkway, Norman, Oklahoma 73019, United States
| |
Collapse
|
11
|
Sastry AV, Hu A, Heckmann D, Poudel S, Kavvas E, Palsson BO. Independent component analysis recovers consistent regulatory signals from disparate datasets. PLoS Comput Biol 2021; 17:e1008647. [PMID: 33529205 PMCID: PMC7888660 DOI: 10.1371/journal.pcbi.1008647] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2020] [Revised: 02/17/2021] [Accepted: 12/18/2020] [Indexed: 01/03/2023] Open
Abstract
The availability of bacterial transcriptomes has dramatically increased in recent years. This data deluge could result in detailed inference of underlying regulatory networks, but the diversity of experimental platforms and protocols introduces critical biases that could hinder scalable analysis of existing data. Here, we show that the underlying structure of the E. coli transcriptome, as determined by Independent Component Analysis (ICA), is conserved across multiple independent datasets, including both RNA-seq and microarray datasets. We subsequently combined five transcriptomics datasets into a large compendium containing over 800 expression profiles and discovered that its underlying ICA-based structure was still comparable to that of the individual datasets. With this understanding, we expanded our analysis to over 3,000 E. coli expression profiles and predicted three high-impact regulons that respond to oxidative stress, anaerobiosis, and antibiotic treatment. ICA thus enables deep analysis of disparate data to uncover new insights that were not visible in the individual datasets. Cells adapt to diverse environments by regulating gene expression. Genome-wide measurements of gene expression levels have exponentially increased in recent years, but successful integration and analysis of these datasets are limited. Recently, we showed that independent component analysis (ICA), a signal deconvolution algorithm, can separate a large bacterial gene expression dataset into groups of co-regulated genes. This previous study focused on data generated by a standardized pipeline and did not address whether ICA extracts the same quantitative co-expression signals across expression profiling platforms. In this study, we show that ICA finds similar co-regulation patterns underlying multiple gene expression datasets and can be used as a tool to integrate and interpret diverse datasets. Using a dataset containing over 3,000 expression profiles, we predicted three new regulons and characterized their activities. Since large, standardized expression datasets only exist for a few bacterial strains, these results broaden the possible applications of this tool to better understand transcriptional regulation across a wide range of microbes.
Collapse
Affiliation(s)
- Anand V. Sastry
- Department of Bioengineering, University of California San Diego, La Jolla, California, United States of America
| | - Alyssa Hu
- Department of Bioengineering, University of California San Diego, La Jolla, California, United States of America
| | - David Heckmann
- Department of Bioengineering, University of California San Diego, La Jolla, California, United States of America
| | - Saugat Poudel
- Department of Bioengineering, University of California San Diego, La Jolla, California, United States of America
| | - Erol Kavvas
- Department of Bioengineering, University of California San Diego, La Jolla, California, United States of America
| | - Bernhard O. Palsson
- Department of Bioengineering, University of California San Diego, La Jolla, California, United States of America
- Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Lyngby, Denmark
- * E-mail:
| |
Collapse
|
12
|
Cetuk H, Anishkin A, Scott AJ, Rempe SB, Ernst RK, Sukharev S. Partitioning of Seven Different Classes of Antibiotics into LPS Monolayers Supports Three Different Permeation Mechanisms through the Outer Bacterial Membrane. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2021; 37:1372-1385. [PMID: 33449700 DOI: 10.1021/acs.langmuir.0c02652] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
The outer membrane (OM) of Gram-negative (G-) bacteria presents a barrier for many classes of antibacterial agents. Lipopolysaccharide (LPS), present in the outer leaflet of the OM, is stabilized by divalent cations and is considered to be the major impediment for antibacterial agent permeation. However, the actual affinities of major antibiotic classes toward LPS have not yet been determined. In the present work, we use Langmuir monolayers formed from E. coli Re and Rd types of LPS to record pressure-area isotherms in the presence of antimicrobial agents. Our observations suggest three general types of interactions. First, some antimicrobials demonstrated no measurable interactions with LPS. This lack of interaction in the case of cefsulodin, a third-generation cephalosporin antibiotic, correlates with its low efficacy against G- bacteria. Ampicillin and ciprofloxacin also show no interactions with LPS, but in contrast to cefsulodin, both exhibit good efficacy against G- bacteria, indicating permeation through common porins. Second, we observe substantial intercalation of the more hydrophobic antibiotics, novobiocin, rifampicin, azithromycin, and telithromycin, into relaxed LPS monolayers. These largely repartition back to the subphase with monolayer compression. We find that the hydrophobic area, charge, and dipole all show correlations with both the mole fraction of antibiotic retained in the monolayer at the monolayer-bilayer equivalence pressure and the efficacies of these antibiotics against G- bacteria. Third, amine-rich gentamicin and the cationic antimicrobial peptides polymyxin B and colistin show no hydrophobic insertion but are instead strongly driven into the polar LPS layer by electrostatic interactions in a pressure-independent manner. Their intercalation stably increases the area per molecule (by up to 20%), which indicates massive formation of defects in the LPS layer. These defects support a self-promoted permeation mechanism of these antibiotics through the OM, which explains the high efficacy and specificity of these antimicrobials against G- bacteria.
Collapse
Affiliation(s)
- Hannah Cetuk
- Biology Department, University of Maryland, College Park, Maryland 20742, United States
| | - Andriy Anishkin
- Biology Department, University of Maryland, College Park, Maryland 20742, United States
| | - Alison J Scott
- Department of Microbial Pathogenesis, University of Maryland, Baltimore, Baltimore Maryland 21201, United States
| | - Susan B Rempe
- Center for Chemical, Biological, Radiation, and Nuclear Defense and Energy Technology, Sandia National Laboratories, Albuquerque, New Mexico 87185, United States
| | - Robert K Ernst
- Department of Microbial Pathogenesis, University of Maryland, Baltimore, Baltimore Maryland 21201, United States
| | - Sergei Sukharev
- Biology Department, University of Maryland, College Park, Maryland 20742, United States
| |
Collapse
|
13
|
Septal Class A Penicillin-Binding Protein Activity and ld-Transpeptidases Mediate Selection of Colistin-Resistant Lipooligosaccharide-Deficient Acinetobacter baumannii. mBio 2021; 12:mBio.02185-20. [PMID: 33402533 PMCID: PMC8545086 DOI: 10.1128/mbio.02185-20] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Despite dogma suggesting that lipopolysaccharide/lipooligosaccharide (LOS) was essential for viability of Gram-negative bacteria, several Acinetobacter baumannii clinical isolates produced LOS− colonies after colistin selection. Inactivation of the conserved class A penicillin-binding protein, PBP1A, was a compensatory mutation that supported isolation of LOS−A. baumannii, but the impact of PBP1A mutation was not characterized. Here, we show that the absence of PBP1A causes septation defects and that these, together with ld-transpeptidase activity, support isolation of LOS−A. baumannii. PBP1A contributes to proper cell division in A. baumannii, and its absence induced cell chaining. Only isolates producing three or more septa supported selection of colistin-resistant LOS−A. baumannii. PBP1A was enriched at the midcell, where the divisome complex facilitates daughter cell formation, and its localization was dependent on glycosyltransferase activity. Transposon mutagenesis showed that genes encoding two putative ld-transpeptidases (LdtJ and LdtK) became essential in the PBP1A mutant. Both LdtJ and LdtK were required for selection of LOS−A. baumannii, but each had distinct enzymatic activities in the cell. Together, these findings demonstrate that defects in PBP1A glycosyltransferase activity and ld-transpeptidase activity remodel the cell envelope to support selection of colistin-resistant LOS−A. baumannii.
Collapse
|
14
|
Kazi MI, Schargel RD, Boll JM. Generating Transposon Insertion Libraries in Gram-Negative Bacteria for High-Throughput Sequencing. J Vis Exp 2020. [PMID: 32716393 DOI: 10.3791/61612] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Transposon sequencing (Tn-seq) is a powerful method that combines transposon mutagenesis and massive parallel sequencing to identify genes and pathways that contribute to bacterial fitness under a wide range of environmental conditions. Tn-seq applications are extensive and have not only enabled examination of genotype-phenotype relationships at an organism level but also at the population, community and systems levels. Gram-negative bacteria are highly associated with antimicrobial resistance phenotypes, which has increased incidents of antibiotic treatment failure. Antimicrobial resistance is defined as bacterial growth in the presence of otherwise lethal antibiotics. The "last-line" antimicrobial colistin is used to treat Gram-negative bacterial infections. However, several Gram-negative pathogens, including Acinetobacter baumannii can develop colistin resistance through a range of molecular mechanisms, some of which were characterized using Tn-seq. Furthermore, signal transduction pathways that regulate colistin resistance vary within Gram-negative bacteria. Here we propose an efficient method of transposon mutagenesis in A. baumannii that streamlines generation of a saturating transposon insertion library and amplicon library construction by eliminating the need for restriction enzymes, adapter ligation, and gel purification. The methods described herein will enable in-depth analysis of molecular determinants that contribute to A. baumannii fitness when challenged with colistin. The protocol is also applicable to other Gram-negative ESKAPE pathogens, which are primarily associated with drug resistant hospital-acquired infections.
Collapse
Affiliation(s)
- Misha I Kazi
- Department of Biology, University of Texas at Arlington
| | | | - Joseph M Boll
- Department of Biology, University of Texas at Arlington;
| |
Collapse
|
15
|
Annunziato G. Strategies to Overcome Antimicrobial Resistance (AMR) Making Use of Non-Essential Target Inhibitors: A Review. Int J Mol Sci 2019; 20:E5844. [PMID: 31766441 PMCID: PMC6928725 DOI: 10.3390/ijms20235844] [Citation(s) in RCA: 100] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2019] [Revised: 11/19/2019] [Accepted: 11/20/2019] [Indexed: 12/23/2022] Open
Abstract
Antibiotics have always been considered as one of the most relevant discoveries of the twentieth century. Unfortunately, the dawn of the antibiotic era has sadly corresponded to the rise of the phenomenon of antimicrobial resistance (AMR), which is a natural process whereby microbes evolve in such a way to withstand the action of drugs. In this context, the identification of new potential antimicrobial targets and/or the identification of new chemical entities as antimicrobial drugs are in great demand. To date, among the many possible approaches used to deal with antibiotic resistance is the use of antibiotic adjuvants that hit bacterial non-essential targets. In this review, the author focuses on the discovery of antibiotic adjuvants and on new tools to study and reduce the prevalence of resistant bacterial infections.
Collapse
Affiliation(s)
- Giannamaria Annunziato
- Probes for Targets Group (P4T group), Department of food and Drug, University of Parma, 43124 Parma, Italy
| |
Collapse
|
16
|
Lehman KM, Grabowicz M. Countering Gram-Negative Antibiotic Resistance: Recent Progress in Disrupting the Outer Membrane with Novel Therapeutics. Antibiotics (Basel) 2019; 8:antibiotics8040163. [PMID: 31554212 PMCID: PMC6963605 DOI: 10.3390/antibiotics8040163] [Citation(s) in RCA: 53] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2019] [Revised: 09/19/2019] [Accepted: 09/20/2019] [Indexed: 10/27/2022] Open
Abstract
Gram-negative bacteria shield themselves from antibiotics by producing an outer membrane (OM) that forms a formidable permeability barrier. Multidrug resistance among these organisms is a particularly acute problem that is exacerbated by the OM. The poor penetrance of many available antibiotics prevents their clinical use, and efforts to discover novel classes of antibiotics against Gram-negative bacteria have been unsuccessful for almost 50 years. Recent insights into how the OM is built offer new hope. Several essential multiprotein molecular machines (Bam, Lpt, and Lol) work in concert to assemble the barrier and offer a swathe of new targets for novel therapeutic development. Murepavadin has been at the vanguard of these efforts, but its recently reported phase III clinical trial toxicity has tempered the anticipation of imminent new clinical options. Nonetheless, the many concerted efforts aimed at breaking down the OM barrier provide a source of ongoing optimism for what may soon come through the development pipeline. We will review the current state of drug development against the OM assembly targets, highlighting insightful new discovery approaches and strategies.
Collapse
Affiliation(s)
- Kelly M Lehman
- Microbiology and Molecular Genetics Program, Graduate Division of Biological and Biomedical Sciences, Laney Graduate School, Emory University, Atlanta, GA 30322, USA.
- Emory Antibiotic Resistance Center, Emory University School of Medicine, Atlanta, GA 30322, USA.
- Department of Microbiology & Immunology, Emory University School of Medicine, Atlanta, GA 30322, USA.
| | - Marcin Grabowicz
- Microbiology and Molecular Genetics Program, Graduate Division of Biological and Biomedical Sciences, Laney Graduate School, Emory University, Atlanta, GA 30322, USA.
- Emory Antibiotic Resistance Center, Emory University School of Medicine, Atlanta, GA 30322, USA.
- Department of Microbiology & Immunology, Emory University School of Medicine, Atlanta, GA 30322, USA.
- Division of Infectious Diseases, Department of Medicine, Emory University School of Medicine, Atlanta, GA 30322, USA.
| |
Collapse
|
17
|
Halder V, Suliman MNS, Kaschani F, Kaiser M. Plant chemical genetics reveals colistin sulphate as a SA and NPR1-independent PR1 inducer functioning via a p38-like kinase pathway. Sci Rep 2019; 9:11196. [PMID: 31371749 PMCID: PMC6671972 DOI: 10.1038/s41598-019-47526-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2019] [Accepted: 07/18/2019] [Indexed: 01/07/2023] Open
Abstract
In plants, low-dose of exogenous bacterial cyclic lipopeptides (CLPs) trigger transient membrane changes leading to activation of early and late defence responses. Here, a forward chemical genetics approach identifies colistin sulphate (CS) CLP as a novel plant defence inducer. CS uniquely triggers activation of the PATHOGENESIS-RELATED 1 (PR1) gene and resistance against Pseudomonas syringae pv. tomato DC3000 (Pst DC3000) in Arabidopsis thaliana (Arabidopsis) independently of the PR1 classical inducer, salicylic acid (SA) and the key SA-signalling protein, NON-EXPRESSOR OF PR1 (NPR1). Low bioactive concentration of CS does not trigger activation of early defence markers such as reactive oxygen species (ROS) and mitogen activated protein kinase (MAPK). However, it strongly suppresses primary root length elongation. Structure activity relationship (SAR) assays and mode-of-action (MoA) studies show the acyl chain and activation of a ∼46 kDa p38-like kinase pathway to be crucial for CS' bioactivity. Selective pharmacological inhibition of the active p38-like kinase pathway by SB203580 reverses CS' effects on PR1 activation and root length suppression. Our results with CS as a chemical probe highlight the existence of a novel SA- and NPR1-independent branch of PR1 activation functioning via a membrane-sensitive p38-like kinase pathway.
Collapse
Affiliation(s)
- Vivek Halder
- Chemical Biology Laboratory, Max Planck Institute of Plant Breeding Research, Carl-von-Linnè-Weg 10, 50829, Köln, Germany. .,Chemical Biology, Centre of Medical Biotechnology, Faculty of Biology, University of Duisburg-Essen, Universitätsstr. 2, 45141, Essen, Germany. .,Rijk Zwaan, De Lier, 2678 ZG, The Netherlands.
| | - Mohamed N S Suliman
- Chemical Biology Laboratory, Max Planck Institute of Plant Breeding Research, Carl-von-Linnè-Weg 10, 50829, Köln, Germany.,Desert Research Centre, 11753 El matareya, Cairo, Egypt
| | - Farnusch Kaschani
- Chemical Biology, Centre of Medical Biotechnology, Faculty of Biology, University of Duisburg-Essen, Universitätsstr. 2, 45141, Essen, Germany
| | - Markus Kaiser
- Chemical Biology, Centre of Medical Biotechnology, Faculty of Biology, University of Duisburg-Essen, Universitätsstr. 2, 45141, Essen, Germany.
| |
Collapse
|
18
|
Douafer H, Andrieu V, Phanstiel O, Brunel JM. Antibiotic Adjuvants: Make Antibiotics Great Again! J Med Chem 2019; 62:8665-8681. [PMID: 31063379 DOI: 10.1021/acs.jmedchem.8b01781] [Citation(s) in RCA: 160] [Impact Index Per Article: 32.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Multiple approaches have been developed to combat bacterial resistance. However, the combination of antibiotic resistance mechanisms by bacteria and the limited number of effective antibiotics available decreases the effective interventions for the treatment of current bacterial infections. This review covers the many ways that bacteria resist antibiotics including antibiotic target modification, the use of efflux pumps, and antibiotic inactivation. As a pertinent example, the use of beta lactamase inhibitors in combination with β-lactam containing antibiotics is discussed in detail. The solution to emerging antibiotic resistance may involve combination therapies of existing antibiotics and potentiating adjuvants, which re-empower the antibiotic agent to become efficacious against the resistant strain of interest. We report herein that a reasoned adjuvant design permits one to perform polypharmacy on bacteria by not only providing greater internal access to the codosed antibiotics but also by de-energizing the efflux pumps used by the bacteria to escape antibiotic action.
Collapse
Affiliation(s)
- Hana Douafer
- Aix Marseille University , INSERM, SSA, MCT , 13385 Marseille , France
| | - Véronique Andrieu
- Aix Marseille University , IRD, APHM, MEPHI, IHU Méditerranée Infection, Faculté de Médecine et de Pharmacie , 13385 Marseille , France
| | - Otto Phanstiel
- 12722 Research Parkway, College of Medicine , University of Central Florida , Orlando , Florida 32826 , United States
| | | |
Collapse
|
19
|
Aghapour Z, Gholizadeh P, Ganbarov K, Bialvaei AZ, Mahmood SS, Tanomand A, Yousefi M, Asgharzadeh M, Yousefi B, Kafil HS. Molecular mechanisms related to colistin resistance in Enterobacteriaceae. Infect Drug Resist 2019; 12:965-975. [PMID: 31190901 PMCID: PMC6519339 DOI: 10.2147/idr.s199844] [Citation(s) in RCA: 184] [Impact Index Per Article: 36.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2018] [Accepted: 03/04/2019] [Indexed: 12/16/2022] Open
Abstract
Colistin is an effective antibiotic for treatment of most multidrug-resistant Gram-negative bacteria. It is used currently as a last-line drug for infections due to severe Gram-negative bacteria followed by an increase in resistance among Gram-negative bacteria. Colistin resistance is considered a serious problem, due to a lack of alternative antibiotics. Some bacteria, including Pseudomonas aeruginosa, Acinetobacter baumannii, Enterobacteriaceae members, such as Escherichia coli, Salmonella spp., and Klebsiella spp. have an acquired resistance against colistin. However, other bacteria, including Serratia spp., Proteus spp. and Burkholderia spp. are naturally resistant to this antibiotic. In addition, clinicians should be alert to the possibility of colistin resistance among multidrug-resistant bacteria and development through mutation or adaptation mechanisms. Rapidly emerging bacterial resistance has made it harder for us to rely completely on the discovery of new antibiotics; therefore, we need to have logical approaches to use old antibiotics, such as colistin. This review presents current knowledge about the different mechanisms of colistin resistance.
Collapse
Affiliation(s)
- Zahra Aghapour
- Drug Applied Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.,Student Research Committee, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Pourya Gholizadeh
- Tuberculosis and Lung Diseases Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | | | | | - Suhad Saad Mahmood
- Department of Biotechnology, College of Science, University of Baghdad, Baghdad, Iraq
| | - Asghar Tanomand
- Department of Microbiology, Maragheh University of Medical Sciences, Maragheh, Iran
| | - Mehdi Yousefi
- Stem Cell Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Mohammad Asgharzadeh
- Biotechnology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Bahman Yousefi
- Biotechnology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Hossein Samadi Kafil
- Drug Applied Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| |
Collapse
|
20
|
Shifting Gears: The Future of Polymyxin Antibiotics. Antibiotics (Basel) 2019; 8:antibiotics8020042. [PMID: 31013818 PMCID: PMC6628003 DOI: 10.3390/antibiotics8020042] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2019] [Revised: 04/05/2019] [Accepted: 04/09/2019] [Indexed: 11/17/2022] Open
Abstract
The manuscripts contained in this special edition of Antibiotics represent a current review of the polymyxins as well as highlights from the 3rd International Polymyxin Conference, which was held in Madrid, Spain, April 25 to 26, 2018. The role of the polymyxin antibiotics has evolved over time based on the availability of alternative agents. After high rates of nephrotoxicity caused the drug class to fall out of favor, polymyxins were once against utilized in the 21st century to combat drug-resistant pathogens. However, the introduction of safer agents with activity against drug-resistant organisms has brought the future utility of polymyxins into question. The present review investigates the future niche of polymyxins by evaluating currently available and future treatment options for difficult-to-treat pathogens. The introduction of ceftazidime-avibactam, meropenem-vaborbactam and plazomicin are likely to decrease polymyxin utilization for infections caused by Enterobacteriaceae. Similarly, the availability of ceftolozane-tazobactam will reduce the use of polymyxins to counter multidrug-resistant Pseudomonas aeruginosa. In contrast, polymyxins will likely continue be an important option for combatting carbapenem-resistant Acinetobacter baumannii until better options become commercially available. Measuring polymyxin concentrations in patients and individualizing therapy may be a future strategy to optimize clinical outcomes while minimizing nephrotoxicity. Inhaled polymyxins will continue to be an adjunctive option for pulmonary infections but further clinical trials are needed to clarify the efficacy of inhaled polymyxins. Lastly, safer polymyxin analogs will potentially be an important addition to the antimicrobial armamentarium.
Collapse
|
21
|
|
22
|
Synergistic Activity of Colistin-Containing Combinations against Colistin-Resistant Enterobacteriaceae. Antimicrob Agents Chemother 2018; 62:AAC.00873-18. [PMID: 30061285 DOI: 10.1128/aac.00873-18] [Citation(s) in RCA: 62] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2018] [Accepted: 07/24/2018] [Indexed: 11/20/2022] Open
Abstract
Resistance to colistin, a polypeptide drug used as an agent of last resort for the treatment of infections caused by multidrug-resistant (MDR) and extensively drug-resistant (XDR) Gram-negative bacteria, including carbapenem-resistant Enterobacteriaceae (CRE), severely limits treatment options and may even transform an XDR organism into one that is pan-resistant. We investigated the synergistic activity of colistin in combination with 19 antibiotics against a collection of 20 colistin-resistant Enterobacteriaceae isolates, 15 of which were also CRE. All combinations were tested against all strains using an inkjet printer-assisted digital dispensing checkerboard array, and the activities of those that demonstrated synergy by this method were evaluated against a single isolate in a time-kill synergy study. Eighteen of 19 combinations demonstrated synergy against two or more isolates, and the 4 most highly synergistic combinations (colistin combined with linezolid, rifampin, azithromycin, and fusidic acid) were synergistic against ≥90% of strains. Sixteen of 18 combinations (88.9%) that were synergistic in the checkerboard array were also synergistic in a time-kill study. Our findings demonstrate that colistin in combination with a range of antibiotics, particularly protein and RNA synthesis inhibitors, exhibits synergy against colistin-resistant strains, suggesting that colistin may exert a subinhibitory permeabilizing effect on the Gram-negative bacterial outer membrane even in isolates that are resistant to it. These findings suggest that colistin combination therapy may have promise as a treatment approach for patients infected with colistin-resistant XDR Gram-negative pathogens.
Collapse
|
23
|
Yu W, Luo Q, Shi Q, Huang C, Yu X, Niu T, Zhou K, Zhang J, Xiao Y. In vitro antibacterial effect of fosfomycin combination therapy against colistin-resistant Klebsiella pneumoniae. Infect Drug Resist 2018; 11:577-585. [PMID: 29731646 PMCID: PMC5926077 DOI: 10.2147/idr.s160474] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Objectives Colistin is still a “last-resort” antibiotic used to manage human infections due to multidrug-resistant (MDR) Klebsiella pneumoniae. However, colistin-resistant K. pneumoniae (CR-Kp) isolates emerged a decade ago and had a worldwide distribution. The purpose of this study was to evaluate the genetic data of CR-Kp and identify the antibacterial activity of fosfomycin (FM) alone and in combination with amikacin (AMK) or colistin (COL) against CR-Kp in vitro. Methods Three clinical CR-Kp isolates from three patients were collected. Whole-genome sequencing and bioinformatics analysis were performed. The Pharmacokinetics Auto Simulation System 400, by simulating human pharmacokinetics in vitro, was employed to simulate FM, AMK, and COL alone and in combination. Different pharmacodynamic parameters were calculated for determining the antimicrobial effect. Results Whole-genome sequencing revealed that none of the three isolates contain mcr gene and that no insertion was found in pmrAB, phoPQ, or mgrB genes. We found the antibacterial activity of AMK alone was more efficient than FM or COL against CR-Kp. The area between the control growth and antibacterial killing curves of FM (8 g every 8 hours) combined with AMK (15 mg/kg once daily) was higher than 170 LogCFU/mL·h−1. In addition, the area between the control growth and antibacterial killing curves of FM (8 g every 8 hours) combined with COL (75,000 IU/kg every12 hours) was higher than that of monotherapies (>100 LogCFU/mL·h−1 vs <80 LogCFU/mL·h−1). Conclusion FM (8 g every 8 hours) combined with AMK (15 mg/kg once daily) was effective at maximizing bacterial killing against CR-Kp.
Collapse
Affiliation(s)
- Wei Yu
- State Key Laboratory for Diagnosis and Treatment of Infectious Disease, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, People's Republic of China.,Department of Infectious Diseases, Zhejiang Provincial People's Hospital, People's Hospital of Hangzhou Medical College, Hangzhou, People's Republic of China
| | - Qixia Luo
- State Key Laboratory for Diagnosis and Treatment of Infectious Disease, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, People's Republic of China
| | - Qingyi Shi
- State Key Laboratory for Diagnosis and Treatment of Infectious Disease, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, People's Republic of China
| | - Chen Huang
- State Key Laboratory for Diagnosis and Treatment of Infectious Disease, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, People's Republic of China
| | - Xiao Yu
- State Key Laboratory for Diagnosis and Treatment of Infectious Disease, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, People's Republic of China
| | - Tianshui Niu
- State Key Laboratory for Diagnosis and Treatment of Infectious Disease, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, People's Republic of China
| | - Kai Zhou
- State Key Laboratory for Diagnosis and Treatment of Infectious Disease, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, People's Republic of China
| | - Jiajie Zhang
- Department of Infectious Diseases, Zhejiang Provincial People's Hospital, People's Hospital of Hangzhou Medical College, Hangzhou, People's Republic of China
| | - Yonghong Xiao
- State Key Laboratory for Diagnosis and Treatment of Infectious Disease, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, People's Republic of China
| |
Collapse
|
24
|
Togashi S, Takahashi K, Tamura A, Toyota I, Hatakeyama S, Komatsuda A, Kudo I, Sasaki Kudoh E, Okamoto T, Haga A, Miyamoto A, Grave E, Sugawara T, Shimizu H, Itoh H. High dose of antibiotic colistin induces oligomerization of molecular chaperone HSP90. J Biochem 2017; 162:27-36. [PMID: 28201527 DOI: 10.1093/jb/mvw104] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2016] [Accepted: 12/15/2016] [Indexed: 11/12/2022] Open
Abstract
Colistin is an antimicrobial cationic peptide that belongs to the polymyxin family. Colistin was clinically used for the treatment of gram-negative infections but fell out of favour because of its significant side effects including neurotoxicity and nephrotoxicity. More recently, colistin has been regarded as one of the important options for nosocomial infections caused by multidrug resistant bacteria. Mechanisms of both the side effect onset of the drug and the side effect reduction are yet to be elucidated. In this study, we identified the specific binding protein of colistin using an affinity column chromatography. Colistin binds to the molecular chaperone HSP90. Although colistin slightly suppressed the chaperone activity of HSP90, there are no effects on the ATPase activity for a low concentration of colistin. Interestingly, colistin-induced aggregation of HSP90 via the N-domain. As for the cell viability of the SHSY5Y cell, the cell viability decreased to approximately 80% by the colistin 300 μM. However, the cell viability recovered to approximately 100% by adding ATP dosage. The same result was obtained by dot blot assay using anti-HSP90 antibody. Our results may help to understand the side effect mechanism of colistin.
Collapse
Affiliation(s)
- Shuntaro Togashi
- Department of Neurosurgery, Akita University Graduate School of Medicine, Akita 010-8543, Japan
| | - Kyosuke Takahashi
- Department of Life Science, Akita University Graduate School of Engineering Science, Akita 010-8502, Japan
| | - Arisa Tamura
- Department of Life Science, Akita University Graduate School of Engineering Science, Akita 010-8502, Japan
| | - Ikumi Toyota
- Department of Life Science, Akita University Graduate School of Engineering Science, Akita 010-8502, Japan
| | - Shiori Hatakeyama
- Department of Life Science, Akita University Graduate School of Engineering Science, Akita 010-8502, Japan
| | - Atsushi Komatsuda
- Department of Hematology, Nephrology, Rheumatology, Akita University Graduate School of Medicine, Akita 010-8543, Japan
| | - Ikuru Kudo
- Department of Life Science, Akita University Graduate School of Engineering Science, Akita 010-8502, Japan
| | - Erina Sasaki Kudoh
- Department of Neurosurgery, Akita University Graduate School of Medicine, Akita 010-8543, Japan
| | - Tomoya Okamoto
- Department of Life Science, Akita University Graduate School of Engineering Science, Akita 010-8502, Japan
| | - Asami Haga
- Department of Life Science, Akita University Graduate School of Engineering Science, Akita 010-8502, Japan
| | - Asuka Miyamoto
- Department of Life Science, Akita University Graduate School of Engineering Science, Akita 010-8502, Japan
| | - Ewa Grave
- Department of Life Science, Akita University Graduate School of Engineering Science, Akita 010-8502, Japan
| | - Taku Sugawara
- Department of Spinal cord and Spine Surgery, Research Institute for Brain and Blood Vessels-Akita, 010-0874 Akita, Japan
| | - Hiroaki Shimizu
- Department of Neurosurgery, Akita University Graduate School of Medicine, Akita 010-8543, Japan
| | - Hideaki Itoh
- Department of Life Science, Akita University Graduate School of Engineering Science, Akita 010-8502, Japan
| |
Collapse
|
25
|
Rajchakit U, Sarojini V. Recent Developments in Antimicrobial-Peptide-Conjugated Gold Nanoparticles. Bioconjug Chem 2017; 28:2673-2686. [DOI: 10.1021/acs.bioconjchem.7b00368] [Citation(s) in RCA: 103] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Urawadee Rajchakit
- School of Chemical Sciences, The University of Auckland, Private Bag, 92019 Auckland, New Zealand
| | - Vijayalekshmi Sarojini
- School of Chemical Sciences, The University of Auckland, Private Bag, 92019 Auckland, New Zealand
| |
Collapse
|
26
|
Jammal J, Zaknoon F, Mor A. Eliciting improved antibacterial efficacy of host proteins in the presence of antibiotics. FASEB J 2017; 32:369-376. [DOI: 10.1096/fj.201700652r] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2017] [Accepted: 08/28/2017] [Indexed: 11/11/2022]
Affiliation(s)
- Joanna Jammal
- Department of Biotechnology and Food EngineeringTechnion‐Israel Institute of Technology Haifa Israel
| | - Fadia Zaknoon
- Department of Biotechnology and Food EngineeringTechnion‐Israel Institute of Technology Haifa Israel
| | - Amram Mor
- Department of Biotechnology and Food EngineeringTechnion‐Israel Institute of Technology Haifa Israel
| |
Collapse
|
27
|
Zhao M, Bulman ZP, Lenhard JR, Satlin MJ, Kreiswirth BN, Walsh TJ, Marrocco A, Bergen PJ, Nation RL, Li J, Zhang J, Tsuji BT. Pharmacodynamics of colistin and fosfomycin: a 'treasure trove' combination combats KPC-producing Klebsiella pneumoniae. J Antimicrob Chemother 2017; 72:1985-1990. [PMID: 28444224 PMCID: PMC5890748 DOI: 10.1093/jac/dkx070] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2016] [Revised: 01/25/2017] [Accepted: 02/12/2017] [Indexed: 12/26/2022] Open
Abstract
Objectives KPC-producing Klebsiella pneumoniae are an emerging public health problem around the globe. We defined the combinatorial pharmacodynamics and ability to suppress resistance of two 'old' antibiotics, fosfomycin and colistin, in time-kill experiments and hollow-fibre infection models (HFIM). Methods Two KPC-2-producing K. pneumoniae isolates were used: one susceptible to both colistin and fosfomycin (KPC 9A: MIC colistin 0.25 mg/L and MIC fosfomycin ≤8 mg/L) and the other resistant to colistin and susceptible to fosfomycin (KPC 5A: MIC colistin 64 mg/L and MIC fosfomycin 32 mg/L). Time-kill experiments assessed an array of colistin and fosfomycin concentrations against both isolates. Colistin and fosfomycin pharmacokinetics from critically ill patients were simulated in the HFIM to define the pharmacodynamic activity of humanized regimens over 5 days against KPC 9A. Results In time-kill experiments, synergy was demonstrated for all colistin/fosfomycin combinations containing >8 mg/L fosfomycin against the double-susceptible KPC strain, 9A. Synergy versus KPC strain 5A was only achieved at the highest concentrations of colistin (4 mg/L) and fosfomycin (512 mg/L) at 48 h. In the HFIM, colistin or fosfomycin monotherapies resulted in rapid proliferation of resistant subpopulations; KPC 9A regrew by 24 h. In contrast to the monotherapies, the colistin/fosfomycin combination resulted in a rapid 6.15 log 10 cfu/mL reduction of KPC 9A by 6 h and complete suppression of resistant subpopulations until 120 h. Conclusions Colistin and fosfomycin may represent an important treatment option for KPC-producing K. pneumoniae otherwise resistant to traditional antibiotics.
Collapse
Affiliation(s)
- Miao Zhao
- Laboratory for Antimicrobial Pharmacodynamics, School of Pharmacy and Pharmaceutical Sciences, University at Buffalo, Buffalo, NY, USA
- Institute of Antibiotics, Huashan Hospital, Fudan University & Key Laboratory of Clinical Pharmacology of Antibiotics, National Health and Family Planning Commission, Shanghai, China
| | - Zackery P. Bulman
- Laboratory for Antimicrobial Pharmacodynamics, School of Pharmacy and Pharmaceutical Sciences, University at Buffalo, Buffalo, NY, USA
| | - Justin R. Lenhard
- Laboratory for Antimicrobial Pharmacodynamics, School of Pharmacy and Pharmaceutical Sciences, University at Buffalo, Buffalo, NY, USA
| | | | | | - Thomas J. Walsh
- Weill Cornell Medicine, Cornell University, New York, NY, USA
| | - Amanda Marrocco
- Laboratory for Antimicrobial Pharmacodynamics, School of Pharmacy and Pharmaceutical Sciences, University at Buffalo, Buffalo, NY, USA
| | - Phillip J. Bergen
- Monash Institute of Pharmaceutical Sciences, Monash University, Melbourne, Australia
| | - Roger L. Nation
- Monash Institute of Pharmaceutical Sciences, Monash University, Melbourne, Australia
| | - Jian Li
- Monash Institute of Pharmaceutical Sciences, Monash University, Melbourne, Australia
| | - Jing Zhang
- Institute of Antibiotics, Huashan Hospital, Fudan University & Key Laboratory of Clinical Pharmacology of Antibiotics, National Health and Family Planning Commission, Shanghai, China
| | - Brian T. Tsuji
- Laboratory for Antimicrobial Pharmacodynamics, School of Pharmacy and Pharmaceutical Sciences, University at Buffalo, Buffalo, NY, USA
| |
Collapse
|
28
|
Mechanisms of envelope permeability and antibiotic influx and efflux in Gram-negative bacteria. Nat Microbiol 2017; 2:17001. [PMID: 28224989 DOI: 10.1038/nmicrobiol.2017.1] [Citation(s) in RCA: 197] [Impact Index Per Article: 28.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2016] [Accepted: 12/23/2016] [Indexed: 01/26/2023]
|
29
|
Development of new polymyxin derivatives for multi-drug resistant Gram-negative infections. J Antibiot (Tokyo) 2017; 70:386-394. [PMID: 28074057 DOI: 10.1038/ja.2016.146] [Citation(s) in RCA: 70] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2016] [Revised: 11/02/2016] [Accepted: 11/12/2016] [Indexed: 12/29/2022]
Abstract
Over the last decade, there has been a resurgence of interest in polymyxins owing to the rapid rise in multi-drug resistant Gram-negative bacteria against which polymyxins offer a last-resort treatment. Although having excellent antibacterial activity, the clinical utility of polymyxins is limited by toxicity, especially renal toxicity. There is much interest therefore in developing polymyxin analogues with an improved therapeutic index. This review describes recent work aimed at improving the activity and/or reducing the toxicity of polymyxins. Consideration to providing activity against emerging strains with reduced susceptibility to polymyxins is also made.
Collapse
|
30
|
Treatment of Gram-negative bacterial infections by potentiation of antibiotics. Curr Opin Microbiol 2016; 33:7-12. [DOI: 10.1016/j.mib.2016.05.005] [Citation(s) in RCA: 78] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2016] [Accepted: 05/08/2016] [Indexed: 12/31/2022]
|
31
|
A penicillin-binding protein inhibits selection of colistin-resistant, lipooligosaccharide-deficient Acinetobacter baumannii. Proc Natl Acad Sci U S A 2016; 113:E6228-E6237. [PMID: 27681618 DOI: 10.1073/pnas.1611594113] [Citation(s) in RCA: 97] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
The Gram-negative bacterial outer membrane fortifies the cell against environmental toxins including antibiotics. Unique glycolipids called lipopolysaccharide/lipooligosaccharide (LPS/LOS) are enriched in the cell-surface monolayer of the outer membrane and promote antimicrobial resistance. Colistin, which targets the lipid A domain of LPS/LOS to lyse the cell, is the last-line treatment for multidrug-resistant Gram-negative infections. Lipid A is essential for the survival of most Gram-negative bacteria, but colistin-resistant Acinetobacter baumannii lacking lipid A were isolated after colistin exposure. Previously, strain ATCC 19606 was the only A. baumannii strain demonstrated to subsist without lipid A. Here, we show that other A. baumannii strains can also survive without lipid A, but some cannot, affording a unique model to study endotoxin essentiality. We assessed the capacity of 15 clinical A. baumannii isolates including 9 recent clinical isolates to develop colistin resistance through inactivation of the lipid A biosynthetic pathway, the products of which assemble the LOS precursor. Our investigation determined that expression of the well-conserved penicillin-binding protein (PBP) 1A, prevented LOS-deficient colony isolation. The glycosyltransferase activity of PBP1A, which aids in the polymerization of the peptidoglycan cell wall, was lethal to LOS-deficient A. baumannii Global transcriptomic analysis of a PBP1A-deficient mutant and four LOS-deficient A. baumannii strains showed a concomitant increase in transcription of lipoproteins and their transporters. Examination of the LOS-deficient A. baumannii cell surface demonstrated that specific lipoproteins were overexpressed and decorated the cell surface, potentially compensating for LOS removal. This work expands our knowledge of lipid A essentiality and elucidates a drug resistance mechanism.
Collapse
|
32
|
Shavrina M, Zimin A, Molochkov N, Chernyshov S, Machulin A, Mikoulinskaia G. In vitro
study of the antibacterial effect of the bacteriophage T5 thermostable endolysin on Escherichia coli
cells. J Appl Microbiol 2016; 121:1282-1290. [DOI: 10.1111/jam.13251] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2016] [Revised: 07/26/2016] [Accepted: 08/03/2016] [Indexed: 01/07/2023]
Affiliation(s)
- M.S. Shavrina
- Branch of Shemyakin & Ovchinnikov's Institute of Bioorganic Chemistry RAS; Pushchino Moscow Russia
| | - A.A. Zimin
- Skryabin's Institute of Biochemistry and Physiology of Micro-organisms RAS; Pushchino Moscow Russia
| | - N.V. Molochkov
- Institute of Theoretical and Experimental Biophysics RAS; Pushchino Moscow Russia
| | - S.V. Chernyshov
- Branch of Shemyakin & Ovchinnikov's Institute of Bioorganic Chemistry RAS; Pushchino Moscow Russia
| | - A.V. Machulin
- Skryabin's Institute of Biochemistry and Physiology of Micro-organisms RAS; Pushchino Moscow Russia
| | - G.V. Mikoulinskaia
- Branch of Shemyakin & Ovchinnikov's Institute of Bioorganic Chemistry RAS; Pushchino Moscow Russia
| |
Collapse
|
33
|
Zachman-Brockmeyer TR, Thoden JB, Holden HM. Structures of KdnB and KdnA from Shewanella oneidensis: Key Enzymes in the Formation of 8-Amino-3,8-Dideoxy-d-Manno-Octulosonic Acid. Biochemistry 2016; 55:4485-94. [PMID: 27275764 DOI: 10.1021/acs.biochem.6b00439] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
8-Amino-3,8-dideoxy-d-manno-octulosonic acid (Kdo8N) is a unique amino sugar that has thus far only been observed on the lipopolysaccharides of marine bacteria belonging to the genus Shewanella. Although its biological function is still unclear, it is thought that the sugar is important for the integrity of the bacterial cell outer membrane. A three-gene cluster required for the biosynthesis of Kdo8N was first identified in Shewanella oneidensis. Here we describe the three-dimensional structures of two of the enzymes required for Kdo8N biosynthesis in S. oneidensis, namely, KdnB and KdnA. The structure of KdnB was solved to 1.85-Å resolution, and its overall three-dimensional architecture places it into the Group III alcohol dehydrogenase superfamily. A previous study suggested that KdnB did not require NAD(P) for activity. Strikingly, although the protein was crystallized in the absence of any cofactors, the electron density map clearly revealed the presence of a tightly bound NAD(H). In addition, a bound metal was observed, which was shown via X-ray fluorescence to be a zinc ion. Unlike other members of the Group III alcohol dehydrogenases, the dinucleotide cofactor in KdnB is tightly bound and cannot be removed without leading to protein precipitation. With respect to KdnA, it is a pyridoxal 5'-phosphate or (PLP)-dependent aminotransferase. For this analysis, the structure of KdnA, trapped in the presence of the external aldimine with PLP and glutamate, was determined to 2.15-Å resolution. The model of KdnA represents the first structure of a sugar aminotransferase that functions on an 8-oxo sugar. Taken together the results reported herein provide new molecular insight into the biosynthesis of Kdo8N.
Collapse
Affiliation(s)
| | - James B Thoden
- Department of Biochemistry, University of Wisconsin , Madison, Wisconsin 53706, United States
| | - Hazel M Holden
- Department of Biochemistry, University of Wisconsin , Madison, Wisconsin 53706, United States
| |
Collapse
|
34
|
Huwaitat R, McCloskey AP, Gilmore BF, Laverty G. Potential strategies for the eradication of multidrug-resistant Gram-negative bacterial infections. Future Microbiol 2016; 11:955-72. [PMID: 27357521 DOI: 10.2217/fmb-2016-0035] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Antimicrobial resistance is one of the leading threats to society. The increasing burden of multidrug-resistant Gram-negative infection is particularly concerning as such bacteria are demonstrating resistance to nearly all currently licensed therapies. Various strategies have been hypothesized to treat multidrug-resistant Gram-negative infections including: targeting the Gram-negative outer membrane; neutralization of lipopolysaccharide; inhibition of bacterial efflux pumps and prevention of protein folding. Silver and silver nanoparticles, fusogenic liposomes and nanotubes are potential strategies for extending the activity of licensed, Gram-positive selective, antibiotics to Gram-negatives. This may serve as a strategy to fill the current void in pharmaceutical development in the short term. This review outlines the most promising strategies that could be implemented to solve the threat of multidrug-resistant Gram-negative infections.
Collapse
Affiliation(s)
- Rawan Huwaitat
- Biofunctional Nanomaterials Group, School of Pharmacy, Queens University of Belfast, Medical Biology Centre, 97 Lisburn Road, Belfast BT9 7BL, UK
| | - Alice P McCloskey
- Biofunctional Nanomaterials Group, School of Pharmacy, Queens University of Belfast, Medical Biology Centre, 97 Lisburn Road, Belfast BT9 7BL, UK
| | - Brendan F Gilmore
- Biofunctional Nanomaterials Group, School of Pharmacy, Queens University of Belfast, Medical Biology Centre, 97 Lisburn Road, Belfast BT9 7BL, UK
| | - Garry Laverty
- Biofunctional Nanomaterials Group, School of Pharmacy, Queens University of Belfast, Medical Biology Centre, 97 Lisburn Road, Belfast BT9 7BL, UK
| |
Collapse
|
35
|
Lee CR, Lee JH, Park KS, Kim YB, Jeong BC, Lee SH. Global Dissemination of Carbapenemase-Producing Klebsiella pneumoniae: Epidemiology, Genetic Context, Treatment Options, and Detection Methods. Front Microbiol 2016; 7:895. [PMID: 27379038 PMCID: PMC4904035 DOI: 10.3389/fmicb.2016.00895] [Citation(s) in RCA: 449] [Impact Index Per Article: 56.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2016] [Accepted: 05/26/2016] [Indexed: 01/08/2023] Open
Abstract
The emergence of carbapenem-resistant Gram-negative pathogens poses a serious threat to public health worldwide. In particular, the increasing prevalence of carbapenem-resistant Klebsiella pneumoniae is a major source of concern. K. pneumoniae carbapenemases (KPCs) and carbapenemases of the oxacillinase-48 (OXA-48) type have been reported worldwide. New Delhi metallo-β-lactamase (NDM) carbapenemases were originally identified in Sweden in 2008 and have spread worldwide rapidly. In this review, we summarize the epidemiology of K. pneumoniae producing three carbapenemases (KPCs, NDMs, and OXA-48-like). Although the prevalence of each resistant strain varies geographically, K. pneumoniae producing KPCs, NDMs, and OXA-48-like carbapenemases have become rapidly disseminated. In addition, we used recently published molecular and genetic studies to analyze the mechanisms by which these three carbapenemases, and major K. pneumoniae clones, such as ST258 and ST11, have become globally prevalent. Because carbapenemase-producing K. pneumoniae are often resistant to most β-lactam antibiotics and many other non-β-lactam molecules, the therapeutic options available to treat infection with these strains are limited to colistin, polymyxin B, fosfomycin, tigecycline, and selected aminoglycosides. Although, combination therapy has been recommended for the treatment of severe carbapenemase-producing K. pneumoniae infections, the clinical evidence for this strategy is currently limited, and more accurate randomized controlled trials will be required to establish the most effective treatment regimen. Moreover, because rapid and accurate identification of the carbapenemase type found in K. pneumoniae may be difficult to achieve through phenotypic antibiotic susceptibility tests, novel molecular detection techniques are currently being developed.
Collapse
Affiliation(s)
- Chang-Ro Lee
- National Leading Research Laboratory of Drug Resistance Proteomics, Department of Biological Sciences, Myongji University Yongin, South Korea
| | - Jung Hun Lee
- National Leading Research Laboratory of Drug Resistance Proteomics, Department of Biological Sciences, Myongji University Yongin, South Korea
| | - Kwang Seung Park
- National Leading Research Laboratory of Drug Resistance Proteomics, Department of Biological Sciences, Myongji University Yongin, South Korea
| | - Young Bae Kim
- Division of STEM, North Shore Community College, Danvers MA, USA
| | - Byeong Chul Jeong
- National Leading Research Laboratory of Drug Resistance Proteomics, Department of Biological Sciences, Myongji University Yongin, South Korea
| | - Sang Hee Lee
- National Leading Research Laboratory of Drug Resistance Proteomics, Department of Biological Sciences, Myongji University Yongin, South Korea
| |
Collapse
|
36
|
Carnicelli D, Arfilli V, Ricci F, Velati C, Tazzari PL, Brigotti M. The Antibiotic Polymyxin B Impairs the Interactions between Shiga Toxins and Human Neutrophils. THE JOURNAL OF IMMUNOLOGY 2015; 196:1177-85. [DOI: 10.4049/jimmunol.1500671] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2015] [Accepted: 11/17/2015] [Indexed: 12/12/2022]
|
37
|
A PmrB-Regulated Deacetylase Required for Lipid A Modification and Polymyxin Resistance in Acinetobacter baumannii. Antimicrob Agents Chemother 2015; 59:7911-4. [PMID: 26459891 DOI: 10.1128/aac.00515-15] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2015] [Accepted: 10/03/2015] [Indexed: 11/20/2022] Open
Abstract
Emerging resistance to "last-resort" polymyxin antibiotics in Gram-negative bacteria is a significant threat to public health. We identified the Acinetobacter baumannii NaxD deacetylase as a critical mediator of lipid A modification resulting in polymyxin resistance and demonstrated that naxD is regulated by the sensor kinase PmrB. This represents the first description of a specific PmrB-regulated gene contributing to polymyxin resistance in A. baumannii and highlights NaxD as a putative drug target to reverse polymyxin resistance.
Collapse
|
38
|
Knolhoff AM, Zheng J, McFarland MA, Luo Y, Callahan JH, Brown EW, Croley TR. Identification and Structural Characterization of Naturally-Occurring Broad-Spectrum Cyclic Antibiotics Isolated from Paenibacillus. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2015; 26:1768-1779. [PMID: 26250559 DOI: 10.1007/s13361-015-1190-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2015] [Revised: 04/24/2015] [Accepted: 05/12/2015] [Indexed: 06/04/2023]
Abstract
The rise of antimicrobial resistance necessitates the discovery and/or production of novel antibiotics. Isolated strains of Paenibacillus alvei were previously shown to exhibit antimicrobial activity against a number of pathogens, such as E. coli, Salmonella, and methicillin-resistant Staphylococcus aureus (MRSA). The responsible antimicrobial compounds were isolated from these Paenibacillus strains and a combination of low and high resolution mass spectrometry with multiple-stage tandem mass spectrometry was used for identification. A group of closely related cyclic lipopeptides was identified, differing primarily by fatty acid chain length and one of two possible amino acid substitutions. Variation in the fatty acid length resulted in mass differences of 14 Da and yielded groups of related MS(n) spectra. Despite the inherent complexity of MS/MS spectra of cyclic compounds, straightforward analysis of these spectra was accomplished by determining differences in complementary product ion series between compounds that differ in molecular weight by 14 Da. The primary peptide sequence assignment was confirmed through genome mining; the combination of these analytical tools represents a workflow that can be used for the identification of complex antibiotics. The compounds also share amino acid sequence similarity to a previously identified broad-spectrum antibiotic isolated from Paenibacillus. The presence of such a wide distribution of related compounds produced by the same organism represents a novel class of broad-spectrum antibiotic compounds.
Collapse
Affiliation(s)
- Ann M Knolhoff
- U.S. Food and Drug Administration, Center for Food Safety and Applied Nutrition, HFS-707, 5100 Paint Branch Pkwy, College Park, MD, 20740, USA.
| | - Jie Zheng
- U.S. Food and Drug Administration, Center for Food Safety and Applied Nutrition, HFS-707, 5100 Paint Branch Pkwy, College Park, MD, 20740, USA
| | - Melinda A McFarland
- U.S. Food and Drug Administration, Center for Food Safety and Applied Nutrition, HFS-707, 5100 Paint Branch Pkwy, College Park, MD, 20740, USA
| | - Yan Luo
- U.S. Food and Drug Administration, Center for Food Safety and Applied Nutrition, HFS-707, 5100 Paint Branch Pkwy, College Park, MD, 20740, USA
| | - John H Callahan
- U.S. Food and Drug Administration, Center for Food Safety and Applied Nutrition, HFS-707, 5100 Paint Branch Pkwy, College Park, MD, 20740, USA
| | - Eric W Brown
- U.S. Food and Drug Administration, Center for Food Safety and Applied Nutrition, HFS-707, 5100 Paint Branch Pkwy, College Park, MD, 20740, USA
| | - Timothy R Croley
- U.S. Food and Drug Administration, Center for Food Safety and Applied Nutrition, HFS-707, 5100 Paint Branch Pkwy, College Park, MD, 20740, USA
| |
Collapse
|
39
|
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: 372] [Impact Index Per Article: 41.3] [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.
Collapse
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
| |
Collapse
|
40
|
Thangamani S, Younis W, Seleem MN. Repurposing celecoxib as a topical antimicrobial agent. Front Microbiol 2015; 6:750. [PMID: 26284040 PMCID: PMC4517059 DOI: 10.3389/fmicb.2015.00750] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2015] [Accepted: 07/08/2015] [Indexed: 01/03/2023] Open
Abstract
There is an urgent need for new antibiotics and alternative strategies to combat multidrug-resistant bacterial pathogens, which are a growing clinical issue. Repurposing existing approved drugs with known pharmacology and toxicology is an alternative strategy to accelerate antimicrobial research and development. In this study, we show that celecoxib, a marketed inhibitor of cyclooxygenase-2, exhibits broad-spectrum antimicrobial activity against Gram-positive pathogens from a variety of genera, including Staphylococcus, Streptococcus, Listeria, Bacillus, and Mycobacterium, but not against Gram-negative pathogens. However, celecoxib is active against all of the Gram-negative bacteria tested, including strains of, Acinetobacter, and Pseudomonas, when their intrinsic resistance is artificially compromised by outer membrane permeabilizing agents such as colistin. The effect of celecoxib on incorporation of radioactive precursors into macromolecules in Staphylococcus aureus was examined. The primary antimicrobial mechanism of action of celecoxib was the dose-dependent inhibition of RNA, DNA, and protein synthesis. Further, we demonstrate the in vivo efficacy of celecoxib in a methicillin-resistant S. aureus (MRSA) infected Caenorhabditis elegans whole animal model. Topical application of celecoxib (1 and 2%) significantly reduced the mean bacterial count in a mouse model of MRSA skin infection. Further, celecoxib decreased the levels of all inflammatory cytokines tested, including tumor necrosis factor-α, interleukin-6, interleukin-1 beta, and monocyte chemo attractant protein-1 in wounds caused by MRSA infection. Celecoxib also exhibited synergy with many conventional antimicrobials when tested against four clinical isolates of S. aureus. Collectively, these results demonstrate that celecoxib alone, or in combination with traditional antimicrobials, has a potential to use as a topical drug for the treatment of bacterial skin infections.
Collapse
Affiliation(s)
| | | | - Mohamed N. Seleem
- Department of Comparative Pathobiology, Purdue University College of Veterinary Medicine, West Lafayette, INUSA
| |
Collapse
|
41
|
Carbapenemase-Producing Klebsiella pneumoniae, a Key Pathogen Set for Global Nosocomial Dominance. Antimicrob Agents Chemother 2015; 59:5873-84. [PMID: 26169401 DOI: 10.1128/aac.01019-15] [Citation(s) in RCA: 548] [Impact Index Per Article: 60.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
The management of infections due to Klebsiella pneumoniae has been complicated by the emergence of antimicrobial resistance, especially to carbapenems. Resistance to carbapenems in K. pneumoniae involves multiple mechanisms, including the production of carbapenemases (e.g., KPC, NDM, VIM, OXA-48-like), as well as alterations in outer membrane permeability mediated by the loss of porins and the upregulation of efflux systems. The latter two mechanisms are often combined with high levels of other types of β-lactamases (e.g., AmpC). K. pneumoniae sequence type 258 (ST258) emerged during the early to mid-2000s as an important human pathogen and has spread extensively throughout the world. ST258 comprises two distinct lineages, namely, clades I and II, and it seems that ST258 is a hybrid clone that was created by a large recombination event between ST11 and ST442. Incompatibility group F plasmids with blaKPC have contributed significantly to the success of ST258. The optimal treatment of infections due to carbapenemase-producing K. pneumoniae remains unknown. Some newer agents show promise for treating infections due to KPC producers; however, effective options for the treatment of NDM producers remain elusive.
Collapse
|
42
|
|
43
|
Saurus P, Kuusela S, Lehtonen E, Hyvönen ME, Ristola M, Fogarty CL, Tienari J, Lassenius MI, Forsblom C, Lehto M, Saleem MA, Groop PH, Holthöfer H, Lehtonen S. Podocyte apoptosis is prevented by blocking the Toll-like receptor pathway. Cell Death Dis 2015; 6:e1752. [PMID: 25950482 PMCID: PMC4669704 DOI: 10.1038/cddis.2015.125] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2014] [Revised: 03/30/2015] [Accepted: 03/31/2015] [Indexed: 12/30/2022]
Abstract
High serum lipopolysaccharide (LPS) activity in normoalbuminuric patients with type 1 diabetes (T1D) predicts the progression of diabetic nephropathy (DN), but the mechanisms behind this remain unclear. We observed that treatment of cultured human podocytes with sera from normoalbuminuric T1D patients with high LPS activity downregulated 3-phosphoinositide-dependent kinase-1 (PDK1), an activator of the Akt cell survival pathway, and induced apoptosis. Knockdown of PDK1 in cultured human podocytes inhibited antiapoptotic Akt pathway, stimulated proapoptotic p38 MAPK pathway, and increased apoptosis demonstrating an antiapoptotic role for PDK1 in podocytes. Interestingly, PDK1 was downregulated in the glomeruli of diabetic rats and patients with type 2 diabetes before the onset of proteinuria, further suggesting that reduced expression of PDK1 associates with podocyte injury and development of DN. Treatment of podocytes in vitro and mice in vivo with LPS reduced PDK1 expression and induced apoptosis, which were prevented by inhibiting the Toll-like receptor (TLR) signaling pathway with the immunomodulatory agent GIT27. Our data show that LPS downregulates the cell survival factor PDK1 and induces podocyte apoptosis, and that blocking the TLR pathway with GIT27 may provide a non-nephrotoxic means to prevent the progression of DN.
Collapse
Affiliation(s)
- P Saurus
- Department of Pathology, University of Helsinki, Helsinki, Finland
| | - S Kuusela
- Department of Pathology, University of Helsinki, Helsinki, Finland
| | - E Lehtonen
- 1] Department of Pathology, University of Helsinki, Helsinki, Finland [2] Laboratory Animal Centre, University of Helsinki, Helsinki, Finland
| | - M E Hyvönen
- Department of Pathology, University of Helsinki, Helsinki, Finland
| | - M Ristola
- Department of Pathology, University of Helsinki, Helsinki, Finland
| | - C L Fogarty
- 1] Folkhälsan Research Center, Folkhälsan Institute of Genetics, Helsinki, Finland [2] Division of Nephrology, Helsinki University Central Hospital, Helsinki, Finland [3] Diabetes and Obesity Research Program, Research Program's Unit, University of Helsinki, Helsinki, Finland
| | - J Tienari
- Department of Pathology, HUSLAB and Helsinki University Hospital, Helsinki and Hyvinkää, Finland
| | - M I Lassenius
- 1] Folkhälsan Research Center, Folkhälsan Institute of Genetics, Helsinki, Finland [2] Division of Nephrology, Helsinki University Central Hospital, Helsinki, Finland [3] Diabetes and Obesity Research Program, Research Program's Unit, University of Helsinki, Helsinki, Finland
| | - C Forsblom
- 1] Folkhälsan Research Center, Folkhälsan Institute of Genetics, Helsinki, Finland [2] Division of Nephrology, Helsinki University Central Hospital, Helsinki, Finland [3] Diabetes and Obesity Research Program, Research Program's Unit, University of Helsinki, Helsinki, Finland
| | - M Lehto
- 1] Folkhälsan Research Center, Folkhälsan Institute of Genetics, Helsinki, Finland [2] Division of Nephrology, Helsinki University Central Hospital, Helsinki, Finland [3] Diabetes and Obesity Research Program, Research Program's Unit, University of Helsinki, Helsinki, Finland
| | - M A Saleem
- Bristol Royal Hospital for Children, University of Bristol, Bristol, UK
| | - P-H Groop
- 1] Folkhälsan Research Center, Folkhälsan Institute of Genetics, Helsinki, Finland [2] Division of Nephrology, Helsinki University Central Hospital, Helsinki, Finland [3] Diabetes and Obesity Research Program, Research Program's Unit, University of Helsinki, Helsinki, Finland [4] Baker IDI Heart and Diabetes Institute, Melbourne, Australia
| | - H Holthöfer
- Department of Bacteriology and Immunology, University of Helsinki, Helsinki, Finland
| | - S Lehtonen
- Department of Pathology, University of Helsinki, Helsinki, Finland
| |
Collapse
|
44
|
Abstract
BACKGROUND Infections caused by multi-drug-resistant Gram-negative bacteria, particularly Acinetobacter baumannii, Pseudomonas aeruginosa and Klebsiella pneumoniae, that cause nosocomial infections, represent a growing problem worldwide. The rapid increase in the prevalence of Gram-negative pathogens that are resistant to fluoroquinolones and aminoglycosides as well as all β-lactams, including carbapenems, monobactam, cephalosporins and broad-spectrum penicillins, has prompted the reconsideration of colistin as a valid therapeutic option. Colistin is an old class of cationic, which act by disrupting the bacterial membranes resulting in cellular death. Although there has been a significant recent increase in the data gathered on colistin, focusing on its chemistry, antibacterial activity, mechanism of action and resistance, pharmacokinetics, pharmacodynamics and new clinical application, the prevalence of colistin resistance has been very little reported in the literature. This review concentrates on recent literature aimed at optimizing the clinical use of this important antibiotic. METHODS The available evidence from various studies (microbiological and clinical studies, retrieved from the PubMed, and Scopus databases) regarding the mechanisms and prevalence of resistance was evaluated. RESULTS Increasing use of colistin for treatment of infections caused by these bacteria has led to the emergence of colistin resistance in several countries worldwide. Although resistance to polymyxins is generally less than 10%, it is higher in the Mediterranean and South-East Asia (Korea and Singapore), where colistin resistance rates are continually increasing. CONCLUSION There is a critical need for effective infection prevention and control measures and strict use of antibiotics in the world to control the rise and spread of colistin resistance.
Collapse
Affiliation(s)
- Abed Zahedi Bialvaei
- Infectious Disease and Tropical Medicine Research Center, Tabriz University of Medical Sciences , Tabriz , Iran
| | | |
Collapse
|
45
|
Lohans CT, van Belkum MJ, Li J, Vederas JC. Characterization of bacterial antimicrobial peptides active against Campylobacter jejuni. CAN J CHEM 2015. [DOI: 10.1139/cjc-2014-0411] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Campylobacter jejuni is one of the major causes of food poisoning, often resulting from the consumption of improperly cooked poultry products. The emergence of C. jejuni strains resistant to conventional antibiotics necessitates the evaluation of other possible treatments or preventative measures to minimize the impact and prevalence of infections. Antimicrobial peptides produced by bacteria have begun to emerge as a potential means of decreasing the levels of C. jejuni in poultry, thereby limiting Campylobacter contamination in associated food products. A number of bacteriocins produced by Gram-positive bacteria have unexpectedly been described as having antimicrobial activity against the Gram-negative C. jejuni. Additionally, some nonribosomal lipopeptides produced by Bacillus and Paenibacillus spp. show efficacy against this pathogen. This review will describe the bacterial antimicrobial peptides reported to be active against C. jejuni, with an emphasis on the characterization of their primary structures. However, for many of these peptides, little is known about their amino acid sequences and structures. Furthermore, there are unusual inconsistencies associated with the reported amino acid sequences for several of the more well-studied bacteriocins. Clarifying the chemical nature of these promising antimicrobial peptides is necessary before their potential utility for livestock protection from C. jejuni can be fully explored. Once these peptides are better characterized, they may prove to be strong candidates for minimizing the impact of Campylobacter on human health.
Collapse
Affiliation(s)
- Christopher T. Lohans
- Department of Chemistry, University of Alberta, 11227 Saskatchewan Drive, Edmonton, AB T6G 2G2, Canada
- Department of Chemistry, University of Alberta, 11227 Saskatchewan Drive, Edmonton, AB T6G 2G2, Canada
| | - Marco J. van Belkum
- Department of Chemistry, University of Alberta, 11227 Saskatchewan Drive, Edmonton, AB T6G 2G2, Canada
- Department of Chemistry, University of Alberta, 11227 Saskatchewan Drive, Edmonton, AB T6G 2G2, Canada
| | - Jing Li
- Department of Chemistry, University of Alberta, 11227 Saskatchewan Drive, Edmonton, AB T6G 2G2, Canada
- Department of Chemistry, University of Alberta, 11227 Saskatchewan Drive, Edmonton, AB T6G 2G2, Canada
| | - John C. Vederas
- Department of Chemistry, University of Alberta, 11227 Saskatchewan Drive, Edmonton, AB T6G 2G2, Canada
- Department of Chemistry, University of Alberta, 11227 Saskatchewan Drive, Edmonton, AB T6G 2G2, Canada
| |
Collapse
|
46
|
Lu S, Walters G, Parg R, Dutcher JR. Nanomechanical response of bacterial cells to cationic antimicrobial peptides. SOFT MATTER 2014; 10:1806-1815. [PMID: 24652481 DOI: 10.1039/c3sm52801d] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The effectiveness of antimicrobial compounds can be easily screened, however their mechanism of action is much more difficult to determine. Many compounds act by compromising the mechanical integrity of the bacterial cell envelope, and our study introduces an AFM-based creep deformation technique to evaluate changes in the time-dependent mechanical properties of Pseudomonas aeruginosa PAO1 bacterial cells upon exposure to two different but structurally related antimicrobial peptides. We observed a distinctive signature for the loss of integrity of the bacterial cell envelope following exposure to the peptides. Measurements performed before and after exposure, as well as time-resolved measurements and those performed at different concentrations, revealed large changes to the viscoelastic parameters that are consistent with differences in the membrane permeabilizing effects of the peptides. The AFM creep deformation measurement provides new, unique insight into the kinetics and mechanism of action of antimicrobial peptides on bacteria.
Collapse
Affiliation(s)
- Shun Lu
- Department of Physics, University of Guelph, Guelph, N1G 2W1, Ontario, Canada.
| | | | | | | |
Collapse
|
47
|
Wang H, Zhang W, Zuo L, Dong J, Zhu W, Li Y, Gu L, Gong J, Li Q, Li N, Li J. Intestinal dysbacteriosis contributes to decreased intestinal mucosal barrier function and increased bacterial translocation. Lett Appl Microbiol 2013; 58:384-92. [PMID: 24354719 DOI: 10.1111/lam.12201] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2013] [Revised: 11/12/2013] [Accepted: 11/22/2013] [Indexed: 12/31/2022]
Abstract
UNLABELLED The purpose of this study was to determine the effect of colistin-induced intestinal dysbacteriosis on intestinal mucosal barrier function and bacterial translocation in a mouse model. Colistin or saline was administered orally for 7 days, and populations of viable organisms from the caecal mucosa and its content, the ileal segments, the mesenteric lymph nodes (MLNs) and the internal organs were prepared for examination. In the intestinal dysbacteriosis model, intestinal barrier dysfunction was observed and associated with increased bacterial translocation to extraintestinal sites. The extent of bacterial translocation to the MLNs and internal organs in the colistin group was significantly higher than in the saline group. Colistin-induced intestinal dysbacteriosis was shown to injure the intestinal mucosa barrier function and increase bacterial dislocation. SIGNIFICANCE AND IMPACT OF THE STUDY Colistin has been reported to be effective in selective digestive decontamination (SDD), which is an infection prevention measure used in the treatment of certain patients in intensive care. We are the first to report that colistin-induced intestinal dysbacteriosis can injure intestinal mucosal barrier function and increase bacterial translocation, whereas a high dose of colistin does not damage the intestinal mucosal barrier in germ-free (GF) mice raised in a GF environment. These results may indicate that prolonged use of a high dose of a SDD medication should be carefully considered.
Collapse
Affiliation(s)
- H Wang
- Department of General Surgery, Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu Province, China
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
48
|
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
|
49
|
Wu H, Teng P, Niu Y, Li Q, Cai J. Polymyxin derivatives: a patent evaluation (WO2012168820). Expert Opin Ther Pat 2013; 23:1075-81. [PMID: 23806121 DOI: 10.1517/13543776.2013.814641] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
The patent application WO201268820 claims a new class of polymyxin derivatives with potent antibacterial activity, especially toward Gram-negative pathogens. Compared to parent polymyxin B (PMB), the new derivatives have more potent antibacterial activity, as well as reduced cytotoxicity against human renal cells.
Collapse
Affiliation(s)
- Haifan Wu
- University of South Florida, Department of Chemistry, 4202 E. Fowler Ave, Tampa, FL 33620, USA
| | | | | | | | | |
Collapse
|
50
|
In vitro activity of daptomycin in combination with low-dose colistin against a diverse collection of Gram-negative bacterial pathogens. Eur J Clin Microbiol Infect Dis 2013; 32:1291-4. [DOI: 10.1007/s10096-013-1875-z] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2013] [Accepted: 03/27/2013] [Indexed: 10/26/2022]
|