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Vergoz D, Schaumann A, Schmitz I, van Agthoven M, Martí S, Vila J, Afonso C, Dé E, Loutelier-Bourhis C, Alexandre S. Direct analysis by ultra-high-resolution mass spectrometry of lipid A and phospholipids from Acinetobacter baumannii cells. Biochimie 2024:S0300-9084(24)00222-0. [PMID: 39326489 DOI: 10.1016/j.biochi.2024.09.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2024] [Revised: 08/13/2024] [Accepted: 09/23/2024] [Indexed: 09/28/2024]
Abstract
Acinetobacter baumannii, classified as priority number one by the World Health Organization (WHO), is an opportunistic pathogen responsible for infection and is able to develop antibiotic resistance easily. Membranes are bacteria's first line of defense against external aggression, such as antibiotics. A chemical modification of a lipid family or a change in lipid composition can lead to resistance to antibiotics. In this work, we analyzed different A. baumannii strains from various environments with different antibiotic resistance profiles, using matrix-assisted laser desorption ionization-Fourier transform ion cyclotron resonance mass spectrometry (MALDI-FT-ICR MS). This study shows that it is possible to describe the main lipidome (phospholipids and lipid A) from the simple preparation of lysed cells, and that despite the complexity of the mixture. This ultra-high resolution mass spectrometry technique enables the separation of isobaric ion, to report a new class of lipids. Given its performance, this technique can be used to quickly and reliably characterize the lipidome of clinical strains from different environments.
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Affiliation(s)
- Delphine Vergoz
- Univ Rouen Normandie, INSA Rouen Normandie, CNRS, Normandie Univ, PBS UMR 6270, Polymers, Biopolymers, Surfaces Lab., 76000 Rouen, France; Univ Rouen Normandie, INSA Rouen Normandie, CNRS, Normandie Univ, COBRA UMR 6014, INC3M FR 3038, F-76000 Rouen, France.
| | - Annick Schaumann
- Univ Rouen Normandie, INSA Rouen Normandie, CNRS, Normandie Univ, PBS UMR 6270, Polymers, Biopolymers, Surfaces Lab., 76000 Rouen, France
| | - Isabelle Schmitz
- Univ Rouen Normandie, INSA Rouen Normandie, CNRS, Normandie Univ, PBS UMR 6270, Polymers, Biopolymers, Surfaces Lab., 76000 Rouen, France; Univ Rouen Normandie, INSA Rouen Normandie, CNRS, Normandie Univ, COBRA UMR 6014, INC3M FR 3038, F-76000 Rouen, France
| | - Maria van Agthoven
- Univ Rouen Normandie, INSA Rouen Normandie, CNRS, Normandie Univ, COBRA UMR 6014, INC3M FR 3038, F-76000 Rouen, France
| | - Sara Martí
- Department of Microbiology, Hospital Universitari de Bellvitge, CIBERes, IDIBELL, Barcelona, Spain
| | - Jordi Vila
- Servei de Microbiologia, Centre de Diagnòstic Biomèdic, Hospital Clínic, ISGLOBAL, Facultat de Medicina, Universitat de Barcelona, Barcelona, Spain
| | - Carlos Afonso
- Univ Rouen Normandie, INSA Rouen Normandie, CNRS, Normandie Univ, COBRA UMR 6014, INC3M FR 3038, F-76000 Rouen, France
| | - Emmanuelle Dé
- Univ Rouen Normandie, INSA Rouen Normandie, CNRS, Normandie Univ, PBS UMR 6270, Polymers, Biopolymers, Surfaces Lab., 76000 Rouen, France
| | - Corinne Loutelier-Bourhis
- Univ Rouen Normandie, INSA Rouen Normandie, CNRS, Normandie Univ, COBRA UMR 6014, INC3M FR 3038, F-76000 Rouen, France
| | - Stéphane Alexandre
- Univ Rouen Normandie, INSA Rouen Normandie, CNRS, Normandie Univ, PBS UMR 6270, Polymers, Biopolymers, Surfaces Lab., 76000 Rouen, France
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2
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Wang WX, Wu JZ, Zhang BL, Yu JY, Han LM, Lu XL, Li H, Fu SY, Ren YY, Dong H, Xu Y, Wang GT, Gao JH, Wang C, Chen XZ, Liu DX, Huang Y, Yu JH, Wang SW, Yang YF, Chen W. Phage therapy combats pan drug-resistant Acinetobacter baumannii infection safely and efficiently. Int J Antimicrob Agents 2024; 64:107220. [PMID: 38810939 DOI: 10.1016/j.ijantimicag.2024.107220] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2023] [Revised: 04/20/2024] [Accepted: 05/20/2024] [Indexed: 05/31/2024]
Abstract
Phage therapy offers a promising approach to combat the growing threat of antimicrobial resistance. Yet, key questions remain regarding dosage, administration routes, combination therapy, and the causes of therapeutic failure. In this study, we focused on a novel lytic phage, ФAb4B, which specifically targeted the Acinetobacter baumannii strains with KL160 capsular polysaccharide, including the pan-drug resistant A. baumannii YQ4. ФAb4B exhibited the ability to effectively inhibit biofilm formation and eradicate mature biofilms independently of dosage. Additionally, it demonstrated a wide spectrum of antibiotic-phage synergy and did not show any cytotoxic or haemolytic effects. Continuous phage injections, both intraperitoneally and intravenously over 7 d, showed no acute toxicity in vivo. Importantly, phage therapy significantly improved neutrophil counts, outperforming ciprofloxacin. However, excessive phage injections suppressed neutrophil levels. The combinatorial treatment of phage-ciprofloxacin rescued 91% of the mice, a superior outcome compared to phage alone (67%). The efficacy of the combinatorial treatment was independent of phage dosage. Notably, prophylactic administration of the combinatorial regimen provided no protection, but even when combined with a delayed therapeutic regimen, it saved all the mice. Bacterial resistance to the phage was not a contributing factor to treatment failure. Our preclinical study systematically describes the lytic phage's effectiveness in both in vitro and in vivo settings, filling in crucial details about phage treatment against bacteriemia caused by A. baumannii, which will provide a robust foundation for the future of phage therapy.
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Affiliation(s)
- Wei-Xiao Wang
- Clinical Research Center, The Second Hospital of Nanjing, Affiliated to Nanjing University of Chinese Medicine, Nanjing, China
| | - Jia-Zhen Wu
- Clinical Research Center, The Second Hospital of Nanjing, Affiliated to Nanjing University of Chinese Medicine, Nanjing, China; Department of Laboratory Medicine, The Second Affiliated Hospital of Nanchang University, Nanchang, China
| | - Bai-Ling Zhang
- Department of Laboratory Medicine, The Second Affiliated Hospital of Nanchang University, Nanchang, China
| | - Jiao-Yang Yu
- Clinical Research Center, The Second Hospital of Nanjing, Affiliated to Nanjing University of Chinese Medicine, Nanjing, China; Key Laboratory of Resources Biology and Biotechnology in Western China, Ministry of Education, College of Life Sciences, Northwest University, Xi'an, China
| | - Li-Mei Han
- Clinical Research Center, The Second Hospital of Nanjing, Affiliated to Nanjing University of Chinese Medicine, Nanjing, China
| | - Xiao-Liang Lu
- Key Laboratory of Resources Biology and Biotechnology in Western China, Ministry of Education, College of Life Sciences, Northwest University, Xi'an, China
| | - Hui Li
- Department of Laboratory Medicine, The Second Affiliated Hospital of Nanchang University, Nanchang, China
| | - Shi-Yong Fu
- Clinical Research Center, The Second Hospital of Nanjing, Affiliated to Nanjing University of Chinese Medicine, Nanjing, China
| | - Yun-Yao Ren
- Clinical Research Center, The Second Hospital of Nanjing, Affiliated to Nanjing University of Chinese Medicine, Nanjing, China
| | - Hui Dong
- Clinical Research Center, The Second Hospital of Nanjing, Affiliated to Nanjing University of Chinese Medicine, Nanjing, China
| | - Yi Xu
- Department of Geriatric Medicine, Jiangxi Provincial People's Hospital, Nanchang, China
| | - Gong-Ting Wang
- Key Laboratory of Resources Biology and Biotechnology in Western China, Ministry of Education, College of Life Sciences, Northwest University, Xi'an, China
| | - Jing-Han Gao
- Clinical Research Center, The Second Hospital of Nanjing, Affiliated to Nanjing University of Chinese Medicine, Nanjing, China
| | - Chun Wang
- Clinical Research Center, The Second Hospital of Nanjing, Affiliated to Nanjing University of Chinese Medicine, Nanjing, China
| | - Xiu-Zhen Chen
- Clinical Research Center, The Second Hospital of Nanjing, Affiliated to Nanjing University of Chinese Medicine, Nanjing, China
| | - Du-Xian Liu
- Department of pathology, the Second Hospital of Nanjing, Affiliated Hospital to Nanjing University of Chinese Medicine, Nanjing, China
| | - Ying Huang
- Department of Infection Control and Management, the Second Hospital of Nanjing, Affiliated Hospital to Nanjing University of Chinese Medicine, Nanjing, China
| | - Jin-Hong Yu
- Department of Clinical Laboratory, the Second Hospital of Nanjing, Affiliated Hospital to Nanjing University of Chinese Medicine, Nanjing, China
| | - Shi-Wei Wang
- Key Laboratory of Resources Biology and Biotechnology in Western China, Ministry of Education, College of Life Sciences, Northwest University, Xi'an, China
| | - Yong-Feng Yang
- The Clinical Infectious Disease Center of Nanjing, Nanjing, China.
| | - Wei Chen
- Clinical Research Center, The Second Hospital of Nanjing, Affiliated to Nanjing University of Chinese Medicine, Nanjing, China.
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3
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Tajer L, Paillart JC, Dib H, Sabatier JM, Fajloun Z, Abi Khattar Z. Molecular Mechanisms of Bacterial Resistance to Antimicrobial Peptides in the Modern Era: An Updated Review. Microorganisms 2024; 12:1259. [PMID: 39065030 PMCID: PMC11279074 DOI: 10.3390/microorganisms12071259] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2024] [Revised: 06/10/2024] [Accepted: 06/18/2024] [Indexed: 07/28/2024] Open
Abstract
Antimicrobial resistance (AMR) poses a serious global health concern, resulting in a significant number of deaths annually due to infections that are resistant to treatment. Amidst this crisis, antimicrobial peptides (AMPs) have emerged as promising alternatives to conventional antibiotics (ATBs). These cationic peptides, naturally produced by all kingdoms of life, play a crucial role in the innate immune system of multicellular organisms and in bacterial interspecies competition by exhibiting broad-spectrum activity against bacteria, fungi, viruses, and parasites. AMPs target bacterial pathogens through multiple mechanisms, most importantly by disrupting their membranes, leading to cell lysis. However, bacterial resistance to host AMPs has emerged due to a slow co-evolutionary process between microorganisms and their hosts. Alarmingly, the development of resistance to last-resort AMPs in the treatment of MDR infections, such as colistin, is attributed to the misuse of this peptide and the high rate of horizontal genetic transfer of the corresponding resistance genes. AMP-resistant bacteria employ diverse mechanisms, including but not limited to proteolytic degradation, extracellular trapping and inactivation, active efflux, as well as complex modifications in bacterial cell wall and membrane structures. This review comprehensively examines all constitutive and inducible molecular resistance mechanisms to AMPs supported by experimental evidence described to date in bacterial pathogens. We also explore the specificity of these mechanisms toward structurally diverse AMPs to broaden and enhance their potential in developing and applying them as therapeutics for MDR bacteria. Additionally, we provide insights into the significance of AMP resistance within the context of host-pathogen interactions.
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Affiliation(s)
- Layla Tajer
- Laboratory of Applied Biotechnology (LBA3B), Azm Center for Research in Biotechnology and Its Applications, Department of Cell Culture, EDST, Lebanese University, Tripoli 1300, Lebanon; (L.T.); (Z.F.)
| | - Jean-Christophe Paillart
- CNRS, Architecture et Réactivité de l’ARN, UPR 9002, Université de Strasbourg, 2 Allée Konrad Roentgen, F-67000 Strasbourg, France;
| | - Hanna Dib
- College of Engineering and Technology, American University of the Middle East, Egaila 54200, Kuwait;
| | - Jean-Marc Sabatier
- CNRS, INP, Inst Neurophysiopathol, Aix-Marseille Université, 13385 Marseille, France
| | - Ziad Fajloun
- Laboratory of Applied Biotechnology (LBA3B), Azm Center for Research in Biotechnology and Its Applications, Department of Cell Culture, EDST, Lebanese University, Tripoli 1300, Lebanon; (L.T.); (Z.F.)
- Department of Biology, Faculty of Sciences 3, Lebanese University, Campus Michel Slayman Ras Maska, Tripoli 1352, Lebanon
| | - Ziad Abi Khattar
- Faculty of Medicine and Medical Sciences, University of Balamand, Kalhat, P.O. Box 100, Tripoli, Lebanon
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García-Romero I, Srivastava M, Monjarás-Feria J, Korankye SO, MacDonald L, Scott NE, Valvano MA. Drug efflux and lipid A modification by 4-L-aminoarabinose are key mechanisms of polymyxin B resistance in the sepsis pathogen Enterobacter bugandensis. J Glob Antimicrob Resist 2024; 37:108-121. [PMID: 38552872 DOI: 10.1016/j.jgar.2024.03.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2023] [Revised: 02/27/2024] [Accepted: 03/14/2024] [Indexed: 04/26/2024] Open
Abstract
OBJECTIVES A concern with the ESKAPE pathogen, Enterobacter bugandensis, and other species of the Enterobacter cloacae complex, is the frequent appearance of multidrug resistance against last-resort antibiotics, such as polymyxins. METHODS Here, we investigated the responses to polymyxin B (PMB) in two PMB-resistant E. bugandensis clinical isolates by global transcriptomics and deletion mutagenesis. RESULTS In both isolates, the genes of the CrrAB-regulated operon, including crrC and kexD, displayed the highest levels of upregulation in response to PMB. ∆crrC and ∆kexD mutants became highly susceptible to PMB and lost the heteroresistant phenotype. Conversely, heterologous expression of CrrC and KexD proteins increased PMB resistance in a sensitive Enterobacter ludwigii clinical isolate and in the Escherichia coli K12 strain, W3110. The efflux pump, AcrABTolC, and the two component regulators, PhoPQ and CrrAB, also contributed to PMB resistance and heteroresistance. Additionally, the lipid A modification with 4-L-aminoarabinose (L-Ara4N), mediated by the arnBCADTEF operon, was critical to determine PMB resistance. Biochemical experiments, supported by mass spectrometry and structural modelling, indicated that CrrC is an inner membrane protein that interacts with the membrane domain of the KexD pump. Similar interactions were modeled for AcrB and AcrD efflux pumps. CONCLUSION Our results support a model where drug efflux potentiated by CrrC interaction with membrane domains of major efflux pumps combined with resistance to PMB entry by the L-Ara4N lipid A modification, under the control of PhoPQ and CrrAB, confers the bacterium high-level resistance and heteroresistance to PMB.
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Affiliation(s)
- Inmaculada García-Romero
- Wellcome-Wolfson Institute for Experimental Medicine, Queen's University Belfast, United Kingdom; Centro Andaluz de Biología del Desarrollo, CSIC-Universidad Pablo de Olavide, Sevilla, Spain
| | - Mugdha Srivastava
- Functional Genomics & Systems Biology Group, Department of Bioinformatics, Biocenter, Am Hubland, University of Wuerzburg, Wuerzburg, Germany; Core Unit Systems Medicine, University of Wuerzburg, Wuerzburg, Germany
| | - Julia Monjarás-Feria
- Wellcome-Wolfson Institute for Experimental Medicine, Queen's University Belfast, United Kingdom
| | - Samuel O Korankye
- Wellcome-Wolfson Institute for Experimental Medicine, Queen's University Belfast, United Kingdom
| | - Lewis MacDonald
- Wellcome-Wolfson Institute for Experimental Medicine, Queen's University Belfast, United Kingdom
| | - Nichollas E Scott
- Department of Microbiology and Immunology, University of Melbourne, Melbourne, Australia
| | - Miguel A Valvano
- Wellcome-Wolfson Institute for Experimental Medicine, Queen's University Belfast, United Kingdom.
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5
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Thadtapong N, Chaturongakul S, Napaswad C, Dubbs P, Soodvilai S. Enhancing effect of natural adjuvant, panduratin A, on antibacterial activity of colistin against multidrug-resistant Acinetobacter baumannii. Sci Rep 2024; 14:9863. [PMID: 38684853 PMCID: PMC11059350 DOI: 10.1038/s41598-024-60627-0] [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: 11/07/2023] [Accepted: 04/25/2024] [Indexed: 05/02/2024] Open
Abstract
Colistin- and carbapenem-resistant Acinetobacter baumannii is a serious multidrug resistant (MDR) bacterium in clinical settings. Discovery of new antibacterial drugs against MDR is facing multiple challenges in drug development. Combination of known antibiotics with a robust adjuvant might be an alternative effective strategy for MDR treatment. In the study herein, we report an antibiotic adjuvant activity of a natural compound panduratin A from fingerroot (Boesenbergia rotunda) as a potent adjuvant to colistin. The present study investigated the antibiotic adjuvant effect of panduratin A against 10 colistin- and carbapenem-resistant A. baumannii. Antibacterial activities were tested by broth microdilution method. Biofilm assay was used to determine the efficacy of panduratin A in biofilm formation inhibition on two representative strains Aci46 and Aci44. Genomic and transcriptomic analyses of colistin- and carbapenem-resistant A. baumannii strains were used to identify potential resistance and tolerance mechanism in the bacteria. Panduratin A-colistin combination showed an increased effect on antibacterial in the A. baumannii. However, panduratin A did not improve the antibacterial activity of imipenem. In addition, panduratin A improves anti-biofilm activity of colistin against Aci44 and Aci46, the colistin- and carbapenem-resistant A. baumannii. Panduratin A markedly enhances bactericidal and anti-biofilm activity of colistin against colistin- resistant A. baumannii. Based on genome comparisons, single nucleotide polymorphism (SNP) patterns in six genes encoding biofilm and lipid A biosynthesis were shared in Aci44 and Aci46. In Aci44, we identified a partial sequence of pmrB encoding a polymyxin resistant component PmrB, whereas a full length of pmrB was observed in Aci46. RNA-seq analyses of Aci44 revealed that panduratin A-colistin combination induced expression of ribosomal proteins and oxidative stress response proteins, whereas iron transporter and MFS-type transporter systems were suppressed. Panduratin A-colistin combination could promote intracellular reactive oxygen species (ROS) accumulation could lead to the cidal effect on colistin-resistant A. baumannii. Combination of panduratin A and colistin showed a significant increase in colistin efficacy against colistin- resistant A. baumannii in comparison of colistin alone. Genomic comparison between Aci44 and Aci46 showed mutations and SNPs that might affect different phenotypes. Additionally, based on RNA-Seq, panduratin A-colistin combination could lead to ROS production and accumulation. These findings confirmed the potency of panduratin as colistin adjuvant against multidrug resistant A. baumannii.
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Affiliation(s)
- Nalumon Thadtapong
- Research Center of Transport Protein for Medical Innovation, Department of Physiology, Faculty of Science, Mahidol University, Bangkok, Thailand
| | - Soraya Chaturongakul
- Center for Advanced Therapeutics, Institute of Molecular Biosciences, Mahidol University, Nakhon Pathom, Thailand
| | - Chanita Napaswad
- Department of Microbiology, Faculty of Science, Mahidol University, Bangkok, Thailand
| | - Padungsri Dubbs
- Department of Microbiology, Faculty of Science, Mahidol University, Bangkok, Thailand
| | - Sunhapas Soodvilai
- Research Center of Transport Protein for Medical Innovation, Department of Physiology, Faculty of Science, Mahidol University, Bangkok, Thailand.
- Excellent Center for Drug Discovery, Mahidol University, Bangkok, Thailand.
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6
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Liu X, Qin P, Wen H, Wang W, Zhao J. Seasonal meropenem resistance in Acinetobacter baumannii and influence of temperature-driven adaptation. BMC Microbiol 2024; 24:149. [PMID: 38678219 PMCID: PMC11055336 DOI: 10.1186/s12866-024-03271-y] [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: 11/28/2023] [Accepted: 03/22/2024] [Indexed: 04/29/2024] Open
Abstract
BACKGROUND Recognition of seasonal trends in bacterial infection and drug resistance rates may enhance diagnosis, direct therapeutic strategies, and inform preventive measures. Limited data exist on the seasonal variability of Acinetobacter baumannii. We investigated the seasonality of A. baumannii, the correlation between temperature and meropenem resistance, and the impact of temperature on this bacterium. RESULTS Meropenem resistance rates increased with lower temperatures, peaking in winter/colder months. Nonresistant strain detection exhibited temperature-dependent seasonality, rising in summer/warmer months and declining in winter/colder months. In contrast, resistant strains showed no seasonality. Variations in meropenem-resistant and nonresistant bacterial resilience to temperature changes were observed. Nonresistant strains displayed growth advantages at temperatures ≥ 25 °C, whereas meropenem-resistant A. baumannii with β-lactamase OXA-23 exhibited greater resistance to low-temperature (4 °C) stress. Furthermore, at 4 °C, A. baumannii upregulated carbapenem resistance-related genes (adeJ, oxa-51, and oxa-23) and increased meropenem stress tolerance. CONCLUSIONS Meropenem resistance rates in A. baumannii display seasonality and are negatively correlated with local temperature, with rates peaking in winter, possibly linked to the differential adaptation of resistant and nonresistant isolates to temperature fluctuations. Furthermore, due to significant resistance rate variations between quarters, compiling monthly or quarterly reports might enhance comprehension of antibiotic resistance trends. Consequently, this could assist in formulating strategies to control and prevent resistance within healthcare facilities.
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Affiliation(s)
- Xiaoxuan Liu
- Hebei Provincial Center for Clinical Laboratories, The Second Hospital of Hebei Medical University, Shijiazhuang, 050000, People's Republic of China
| | - Pu Qin
- Hebei Provincial Center for Clinical Laboratories, The Second Hospital of Hebei Medical University, Shijiazhuang, 050000, People's Republic of China
| | - Hainan Wen
- Department of Laboratory Medicine, Affiliated Hospital of Chengde Medical University, Chengde, 067000, People's Republic of China
| | - Weigang Wang
- Hebei Provincial Center for Clinical Laboratories, The Second Hospital of Hebei Medical University, Shijiazhuang, 050000, People's Republic of China
| | - Jianhong Zhao
- Hebei Provincial Center for Clinical Laboratories, The Second Hospital of Hebei Medical University, Shijiazhuang, 050000, People's Republic of China.
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7
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Mulukutla A, Shreshtha R, Kumar Deb V, Chatterjee P, Jain U, Chauhan N. Recent advances in antimicrobial peptide-based therapy. Bioorg Chem 2024; 145:107151. [PMID: 38359706 DOI: 10.1016/j.bioorg.2024.107151] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2023] [Revised: 01/05/2024] [Accepted: 01/22/2024] [Indexed: 02/17/2024]
Abstract
Antimicrobial peptides (AMPs) are a group of polypeptide chains that have the property to target and kill a myriad of microbial organisms including viruses, bacteria, protists, etc. The first discovered AMP was named gramicidin, an extract of aerobic soil bacteria. Further studies discovered that these peptides are present not only in prokaryotes but in eukaryotes as well. They play a vital role in human innate immunity and wound repair. Consequently, they have maintained a high level of intrigue among scientists in the field of immunology, especially so with the rise of antibiotic-resistant pathogens decreasing the reliability of antibiotics in healthcare. While AMPs have promising potential to substitute for common antibiotics, their use as effective replacements is barred by certain limitations. First, they have the potential to be cytotoxic to human cells. Second, they are unstable in the blood due to action by various proteolytic agents and ions that cause their degradation. This review provides an overview of the mechanism of AMPs, their limitations, and developments in recent years that provide techniques to overcome those limitations. We also discuss the advantages and drawbacks of AMPs as a replacement for antibiotics as compared to other alternatives such as synthetically modified bacteriophages, traditional medicine, and probiotics.
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Affiliation(s)
- Aditya Mulukutla
- School of Health Sciences and Technology, UPES, Dehradun 248007, Uttarakhand, India
| | - Romi Shreshtha
- School of Health Sciences and Technology, UPES, Dehradun 248007, Uttarakhand, India
| | - Vishal Kumar Deb
- School of Health Sciences and Technology, UPES, Dehradun 248007, Uttarakhand, India
| | - Pallabi Chatterjee
- School of Health Sciences and Technology, UPES, Dehradun 248007, Uttarakhand, India
| | - Utkarsh Jain
- School of Health Sciences and Technology, UPES, Dehradun 248007, Uttarakhand, India
| | - Nidhi Chauhan
- School of Health Sciences and Technology, UPES, Dehradun 248007, Uttarakhand, India.
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8
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VanOtterloo LM, Macias LA, Powers MJ, Brodbelt JS, Trent MS. Characterization of Acinetobacter baumannii core oligosaccharide synthesis reveals novel aspects of lipooligosaccharide assembly. mBio 2024; 15:e0301323. [PMID: 38349180 PMCID: PMC10936431 DOI: 10.1128/mbio.03013-23] [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: 11/06/2023] [Accepted: 01/12/2024] [Indexed: 03/14/2024] Open
Abstract
A fundamental feature of Gram-negative bacteria is their outer membrane that protects the cell against environmental stressors. This defense is predominantly due to its asymmetry, with glycerophospholipids located in the inner leaflet and lipopolysaccharide (LPS) or lipooligosaccharide (LOS) confined to the outer leaflet. LPS consists of a lipid A anchor, a core oligosaccharide, and a distal O-antigen while LOS lacks O-antigen. While LPS/LOS is typically essential for growth, this is not the case for Acinetobacter baumannii. Despite this unique property, the synthesis of the core oligosaccharide of A. baumannii LOS is not well-described. Here, we characterized the LOS chemotypes of A. baumannii strains with mutations in a predicted core oligosaccharide locus via tandem mass spectrometry. This allowed for an extensive identification of genes required for core assembly that can be exploited to generate precise structural LOS modifications in many A. baumannii strains. We further investigated two chemotypically identical yet phenotypically distinct mutants, ∆2903 and ∆lpsB, that exposed a possible link between LOS and the peptidoglycan cell wall-two cell envelope components whose coordination has not yet been described in A. baumannii. Selective reconstruction of the core oligosaccharide via expression of 2903 and LpsB revealed that these proteins rely on each other for the unusual tandem transfer of two residues, KdoIII and N-acetylglucosaminuronic acid. The data presented not only allow for better usage of A. baumannii as a tool to study outer membrane integrity but also provide further evidence for a novel mechanism of core oligosaccharide assembly. IMPORTANCE Acinetobacter baumannii is a multidrug-resistant pathogen that produces lipooligosaccharide (LOS), a glycolipid that confers protective asymmetry to the bacterial outer membrane. The core oligosaccharide is a ubiquitous component of LOS that typically follows a well-established model of synthesis. In addition to providing an extensive analysis of the genes involved in the synthesis of the core region, we demonstrate that this organism has evidently diverged from the long-held archetype of core synthesis. Moreover, our data suggest that A. baumannii LOS assembly is important for cell division and likely intersects with the synthesis of the peptidoglycan cell wall, another essential component of the Gram-negative cell envelope. This connection between LOS and cell wall synthesis provides an intriguing foundation for a unique method of outer membrane biogenesis and cell envelope coordination.
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Affiliation(s)
- Leah M. VanOtterloo
- Department of Microbiology, College of Art and Sciences, University of Georgia, Athens, Georgia, USA
| | - Luis A. Macias
- Department of Chemistry, University of Texas at Austin, Austin, Texas, USA
| | - Matthew J. Powers
- Department of Microbiology, College of Art and Sciences, University of Georgia, Athens, Georgia, USA
| | | | - M. Stephen Trent
- Department of Microbiology, College of Art and Sciences, University of Georgia, Athens, Georgia, USA
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, Georgia, USA
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9
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Zampaloni C, Mattei P, Bleicher K, Winther L, Thäte C, Bucher C, Adam JM, Alanine A, Amrein KE, Baidin V, Bieniossek C, Bissantz C, Boess F, Cantrill C, Clairfeuille T, Dey F, Di Giorgio P, du Castel P, Dylus D, Dzygiel P, Felici A, García-Alcalde F, Haldimann A, Leipner M, Leyn S, Louvel S, Misson P, Osterman A, Pahil K, Rigo S, Schäublin A, Scharf S, Schmitz P, Stoll T, Trauner A, Zoffmann S, Kahne D, Young JAT, Lobritz MA, Bradley KA. A novel antibiotic class targeting the lipopolysaccharide transporter. Nature 2024; 625:566-571. [PMID: 38172634 PMCID: PMC10794144 DOI: 10.1038/s41586-023-06873-0] [Citation(s) in RCA: 41] [Impact Index Per Article: 41.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2022] [Accepted: 11/16/2023] [Indexed: 01/05/2024]
Abstract
Carbapenem-resistant Acinetobacter baumannii (CRAB) has emerged as a major global pathogen with limited treatment options1. No new antibiotic chemical class with activity against A. baumannii has reached patients in over 50 years1. Here we report the identification and optimization of tethered macrocyclic peptide (MCP) antibiotics with potent antibacterial activity against CRAB. The mechanism of action of this molecule class involves blocking the transport of bacterial lipopolysaccharide from the inner membrane to its destination on the outer membrane, through inhibition of the LptB2FGC complex. A clinical candidate derived from the MCP class, zosurabalpin (RG6006), effectively treats highly drug-resistant contemporary isolates of CRAB both in vitro and in mouse models of infection, overcoming existing antibiotic resistance mechanisms. This chemical class represents a promising treatment paradigm for patients with invasive infections due to CRAB, for whom current treatment options are inadequate, and additionally identifies LptB2FGC as a tractable target for antimicrobial drug development.
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Affiliation(s)
- Claudia Zampaloni
- Roche Pharma Research and Early Development, Immunology, Infectious Disease and Ophthalmology, Roche Innovation Center Basel, F. Hoffmann-La Roche, Basel, Switzerland
| | - Patrizio Mattei
- Roche Pharma Research and Early Development, Therapeutic Modalities, Roche Innovation Center Basel, F. Hoffmann-La Roche, Basel, Switzerland
| | - Konrad Bleicher
- Roche Pharma Research and Early Development, Therapeutic Modalities, Roche Innovation Center Basel, F. Hoffmann-La Roche, Basel, Switzerland
- SixPeaks Bio, Basel, Switzerland
| | - Lotte Winther
- Roche Pharma Research and Early Development, Pharmaceutical Sciences, Roche Innovation Center Basel, F. Hoffmann-La Roche, Basel, Switzerland
| | - Claudia Thäte
- Roche Pharma Research and Early Development, Pharmaceutical Sciences, Roche Innovation Center Basel, F. Hoffmann-La Roche, Basel, Switzerland
- Preclinical Sciences and Translational Safety, Janssen Pharmaceutica, Beerse, Belgium
| | - Christian Bucher
- Roche Pharma Research and Early Development, Therapeutic Modalities, Roche Innovation Center Basel, F. Hoffmann-La Roche, Basel, Switzerland
| | - Jean-Michel Adam
- Roche Pharma Research and Early Development, Therapeutic Modalities, Roche Innovation Center Basel, F. Hoffmann-La Roche, Basel, Switzerland
- AutoChem R&D, Mettler-Toledo International, Greifensee, Switzerland
| | - Alexander Alanine
- Roche Pharma Research and Early Development, Therapeutic Modalities, Roche Innovation Center Basel, F. Hoffmann-La Roche, Basel, Switzerland
- Independent consultant, Cambridge, Great Britain
| | - Kurt E Amrein
- Roche Pharma Research and Early Development, Immunology, Infectious Disease and Ophthalmology, Roche Innovation Center Basel, F. Hoffmann-La Roche, Basel, Switzerland
| | - Vadim Baidin
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA, USA
| | - Christoph Bieniossek
- Roche Pharma Research and Early Development, Immunology, Infectious Disease and Ophthalmology, Roche Innovation Center Basel, F. Hoffmann-La Roche, Basel, Switzerland
| | - Caterina Bissantz
- Roche Pharma Research and Early Development, Pharmaceutical Sciences, Roche Innovation Center Basel, F. Hoffmann-La Roche, Basel, Switzerland
| | - Franziska Boess
- Roche Pharma Research and Early Development, Pharmaceutical Sciences, Roche Innovation Center Basel, F. Hoffmann-La Roche, Basel, Switzerland
| | - Carina Cantrill
- Roche Pharma Research and Early Development, Pharmaceutical Sciences, Roche Innovation Center Basel, F. Hoffmann-La Roche, Basel, Switzerland
| | - Thomas Clairfeuille
- Roche Pharma Research and Early Development, Therapeutic Modalities, Roche Innovation Center Basel, F. Hoffmann-La Roche, Basel, Switzerland
| | - Fabian Dey
- Roche Pharma Research and Early Development, Therapeutic Modalities, Roche Innovation Center Basel, F. Hoffmann-La Roche, Basel, Switzerland
| | - Patrick Di Giorgio
- Roche Pharma Research and Early Development, Therapeutic Modalities, Roche Innovation Center Basel, F. Hoffmann-La Roche, Basel, Switzerland
| | - Pauline du Castel
- Roche Pharma Research and Early Development, Therapeutic Modalities, Roche Innovation Center Basel, F. Hoffmann-La Roche, Basel, Switzerland
| | - David Dylus
- Roche Pharma Research and Early Development, Immunology, Infectious Disease and Ophthalmology, Roche Innovation Center Basel, F. Hoffmann-La Roche, Basel, Switzerland
| | - Pawel Dzygiel
- Roche Pharma Research and Early Development, Pharmaceutical Sciences, Roche Innovation Center Basel, F. Hoffmann-La Roche, Basel, Switzerland
| | - Antonio Felici
- Discovery Microbiology, Aptuit (Verona) Srl, an Evotec Company, Verona, Italy
| | - Fernando García-Alcalde
- Roche Pharma Research and Early Development, Immunology, Infectious Disease and Ophthalmology, Roche Innovation Center Basel, F. Hoffmann-La Roche, Basel, Switzerland
| | - Andreas Haldimann
- Roche Pharma Research and Early Development, Immunology, Infectious Disease and Ophthalmology, Roche Innovation Center Basel, F. Hoffmann-La Roche, Basel, Switzerland
| | - Matthew Leipner
- Roche Pharma Research and Early Development, Immunology, Infectious Disease and Ophthalmology, Roche Innovation Center Basel, F. Hoffmann-La Roche, Basel, Switzerland
- Roche Pharma Research and Early Development, Pharmaceutical Sciences, Roche Innovation Center Basel, F. Hoffmann-La Roche, Basel, Switzerland
| | - Semen Leyn
- Infectious and Inflammatory Disease Center, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA, USA
| | - Séverine Louvel
- Roche Pharma Research and Early Development, Immunology, Infectious Disease and Ophthalmology, Roche Innovation Center Basel, F. Hoffmann-La Roche, Basel, Switzerland
| | - Pauline Misson
- Roche Pharma Research and Early Development, Immunology, Infectious Disease and Ophthalmology, Roche Innovation Center Basel, F. Hoffmann-La Roche, Basel, Switzerland
| | - Andrei Osterman
- Infectious and Inflammatory Disease Center, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA, USA
| | - Karanbir Pahil
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA, USA
| | - Sébastien Rigo
- Roche Pharma Research and Early Development, Immunology, Infectious Disease and Ophthalmology, Roche Innovation Center Basel, F. Hoffmann-La Roche, Basel, Switzerland
| | - Adrian Schäublin
- Roche Pharma Research and Early Development, Therapeutic Modalities, Roche Innovation Center Basel, F. Hoffmann-La Roche, Basel, Switzerland
- SixPeaks Bio, Basel, Switzerland
| | - Sebastian Scharf
- Roche Pharma Research and Early Development, Informatics, Roche Innovation Center Basel, F. Hoffmann-La Roche, Basel, Switzerland
| | - Petra Schmitz
- Roche Pharma Research and Early Development, Therapeutic Modalities, Roche Innovation Center Basel, F. Hoffmann-La Roche, Basel, Switzerland
| | - Theodor Stoll
- Roche Pharma Research and Early Development, Therapeutic Modalities, Roche Innovation Center Basel, F. Hoffmann-La Roche, Basel, Switzerland
| | - Andrej Trauner
- Roche Pharma Research and Early Development, Immunology, Infectious Disease and Ophthalmology, Roche Innovation Center Basel, F. Hoffmann-La Roche, Basel, Switzerland
| | - Sannah Zoffmann
- Roche Pharma Research and Early Development, Therapeutic Modalities, Roche Innovation Center Basel, F. Hoffmann-La Roche, Basel, Switzerland
- Therapeutics Discovery, Janssen Pharmaceutica, Beerse, Belgium
| | - Daniel Kahne
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA, USA
| | - John A T Young
- Roche Pharma Research and Early Development, Immunology, Infectious Disease and Ophthalmology, Roche Innovation Center Basel, F. Hoffmann-La Roche, Basel, Switzerland
| | - Michael A Lobritz
- Roche Pharma Research and Early Development, Immunology, Infectious Disease and Ophthalmology, Roche Innovation Center Basel, F. Hoffmann-La Roche, Basel, Switzerland.
| | - Kenneth A Bradley
- Roche Pharma Research and Early Development, Immunology, Infectious Disease and Ophthalmology, Roche Innovation Center Basel, F. Hoffmann-La Roche, Basel, Switzerland.
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10
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Pahil KS, Gilman MSA, Baidin V, Clairfeuille T, Mattei P, Bieniossek C, Dey F, Muri D, Baettig R, Lobritz M, Bradley K, Kruse AC, Kahne D. A new antibiotic traps lipopolysaccharide in its intermembrane transporter. Nature 2024; 625:572-577. [PMID: 38172635 PMCID: PMC10794137 DOI: 10.1038/s41586-023-06799-7] [Citation(s) in RCA: 20] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Accepted: 10/30/2023] [Indexed: 01/05/2024]
Abstract
Gram-negative bacteria are extraordinarily difficult to kill because their cytoplasmic membrane is surrounded by an outer membrane that blocks the entry of most antibiotics. The impenetrable nature of the outer membrane is due to the presence of a large, amphipathic glycolipid called lipopolysaccharide (LPS) in its outer leaflet1. Assembly of the outer membrane requires transport of LPS across a protein bridge that spans from the cytoplasmic membrane to the cell surface. Maintaining outer membrane integrity is essential for bacterial cell viability, and its disruption can increase susceptibility to other antibiotics2-6. Thus, inhibitors of the seven lipopolysaccharide transport (Lpt) proteins that form this transenvelope transporter have long been sought. A new class of antibiotics that targets the LPS transport machine in Acinetobacter was recently identified. Here, using structural, biochemical and genetic approaches, we show that these antibiotics trap a substrate-bound conformation of the LPS transporter that stalls this machine. The inhibitors accomplish this by recognizing a composite binding site made up of both the Lpt transporter and its LPS substrate. Collectively, our findings identify an unusual mechanism of lipid transport inhibition, reveal a druggable conformation of the Lpt transporter and provide the foundation for extending this class of antibiotics to other Gram-negative pathogens.
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Affiliation(s)
- Karanbir S Pahil
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA, USA
| | - Morgan S A Gilman
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA, USA
| | - Vadim Baidin
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA, USA
| | - Thomas Clairfeuille
- Departments of Immunology, Infectious Disease and Ophthalmology (I2O), Medicinal Chemistry and Lead Discovery, Roche Pharma Research and Early Development, Roche Innovation Center Basel, Basel, Switzerland
| | - Patrizio Mattei
- Departments of Immunology, Infectious Disease and Ophthalmology (I2O), Medicinal Chemistry and Lead Discovery, Roche Pharma Research and Early Development, Roche Innovation Center Basel, Basel, Switzerland
| | - Christoph Bieniossek
- Departments of Immunology, Infectious Disease and Ophthalmology (I2O), Medicinal Chemistry and Lead Discovery, Roche Pharma Research and Early Development, Roche Innovation Center Basel, Basel, Switzerland
| | - Fabian Dey
- Departments of Immunology, Infectious Disease and Ophthalmology (I2O), Medicinal Chemistry and Lead Discovery, Roche Pharma Research and Early Development, Roche Innovation Center Basel, Basel, Switzerland
| | - Dieter Muri
- Departments of Immunology, Infectious Disease and Ophthalmology (I2O), Medicinal Chemistry and Lead Discovery, Roche Pharma Research and Early Development, Roche Innovation Center Basel, Basel, Switzerland
| | - Remo Baettig
- Departments of Immunology, Infectious Disease and Ophthalmology (I2O), Medicinal Chemistry and Lead Discovery, Roche Pharma Research and Early Development, Roche Innovation Center Basel, Basel, Switzerland
| | - Michael Lobritz
- Departments of Immunology, Infectious Disease and Ophthalmology (I2O), Medicinal Chemistry and Lead Discovery, Roche Pharma Research and Early Development, Roche Innovation Center Basel, Basel, Switzerland
| | - Kenneth Bradley
- Departments of Immunology, Infectious Disease and Ophthalmology (I2O), Medicinal Chemistry and Lead Discovery, Roche Pharma Research and Early Development, Roche Innovation Center Basel, Basel, Switzerland
| | - Andrew C Kruse
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA, USA.
| | - Daniel Kahne
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA, USA.
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11
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Vergoz D, Le H, Bernay B, Schaumann A, Barreau M, Nilly F, Desriac F, Tahrioui A, Giard JC, Lesouhaitier O, Chevalier S, Brunel JM, Muller C, Dé E. Antibiofilm and Antivirulence Properties of 6-Polyaminosteroid Derivatives against Antibiotic-Resistant Bacteria. Antibiotics (Basel) 2023; 13:8. [PMID: 38275318 PMCID: PMC10812528 DOI: 10.3390/antibiotics13010008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2023] [Revised: 12/15/2023] [Accepted: 12/18/2023] [Indexed: 01/27/2024] Open
Abstract
The emergence of multi-drug resistant pathogens is a major public health problem, leading us to rethink and innovate our bacterial control strategies. Here, we explore the antibiofilm and antivirulence activities of nineteen 6-polyaminosterol derivatives (squalamine-based), presenting a modulation of their polyamine side chain on four major pathogens, i.e., carbapenem-resistant A. baumannii (CRAB) and P. aeruginosa (CRPA), methicillin-resistant S. aureus (MRSA), and vancomycin-resistant E. faecium (VRE) strains. We screened the effect of these derivatives on biofilm formation and eradication. Derivatives 4e (for CRAB, VRE, and MRSA) and 4f (for all the strains) were the most potent ones and displayed activities as good as those of conventional antibiotics. We also identified 11 compounds able to decrease by more than 40% the production of pyocyanin, a major virulence factor of P. aeruginosa. We demonstrated that 4f treatment acts against bacterial infections in Galleria mellonella and significantly prolonged larvae survival (from 50% to 80%) after 24 h of CRAB, VRE, and MRSA infections. As shown by proteomic studies, 4f triggered distinct cellular responses depending on the bacterial species but essentially linked to cell envelope. Its interesting antibiofilm and antivirulence properties make it a promising a candidate for use in therapeutics.
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Affiliation(s)
- Delphine Vergoz
- Univ Rouen Normandie, INSA Rouen Normandie, CNRS, Normandie Univ, PBS UMR 6270, F-76000 Rouen, France; (D.V.); (H.L.); (A.S.)
| | - Hung Le
- Univ Rouen Normandie, INSA Rouen Normandie, CNRS, Normandie Univ, PBS UMR 6270, F-76000 Rouen, France; (D.V.); (H.L.); (A.S.)
| | - Benoit Bernay
- Univ Caen Normandie, Proteogen Platform, US EMERODE, F-14000 Caen, France;
| | - Annick Schaumann
- Univ Rouen Normandie, INSA Rouen Normandie, CNRS, Normandie Univ, PBS UMR 6270, F-76000 Rouen, France; (D.V.); (H.L.); (A.S.)
| | - Magalie Barreau
- Univ Rouen Normandie, Univ Caen Normandie, Normandie Univ, Communication Bactérienne et Stratégies Anti-Infectieuses, CBSA UR4312, F-76000 Rouen, France; (M.B.); (F.N.); (F.D.); (A.T.); (O.L.); (S.C.)
| | - Flore Nilly
- Univ Rouen Normandie, Univ Caen Normandie, Normandie Univ, Communication Bactérienne et Stratégies Anti-Infectieuses, CBSA UR4312, F-76000 Rouen, France; (M.B.); (F.N.); (F.D.); (A.T.); (O.L.); (S.C.)
| | - Florie Desriac
- Univ Rouen Normandie, Univ Caen Normandie, Normandie Univ, Communication Bactérienne et Stratégies Anti-Infectieuses, CBSA UR4312, F-76000 Rouen, France; (M.B.); (F.N.); (F.D.); (A.T.); (O.L.); (S.C.)
| | - Ali Tahrioui
- Univ Rouen Normandie, Univ Caen Normandie, Normandie Univ, Communication Bactérienne et Stratégies Anti-Infectieuses, CBSA UR4312, F-76000 Rouen, France; (M.B.); (F.N.); (F.D.); (A.T.); (O.L.); (S.C.)
| | | | - Olivier Lesouhaitier
- Univ Rouen Normandie, Univ Caen Normandie, Normandie Univ, Communication Bactérienne et Stratégies Anti-Infectieuses, CBSA UR4312, F-76000 Rouen, France; (M.B.); (F.N.); (F.D.); (A.T.); (O.L.); (S.C.)
| | - Sylvie Chevalier
- Univ Rouen Normandie, Univ Caen Normandie, Normandie Univ, Communication Bactérienne et Stratégies Anti-Infectieuses, CBSA UR4312, F-76000 Rouen, France; (M.B.); (F.N.); (F.D.); (A.T.); (O.L.); (S.C.)
| | | | - Cécile Muller
- Univ Rouen Normandie, Univ Caen Normandie, Normandie Univ, Communication Bactérienne et Stratégies Anti-Infectieuses, CBSA UR4312, F-76000 Rouen, France; (M.B.); (F.N.); (F.D.); (A.T.); (O.L.); (S.C.)
| | - Emmanuelle Dé
- Univ Rouen Normandie, INSA Rouen Normandie, CNRS, Normandie Univ, PBS UMR 6270, F-76000 Rouen, France; (D.V.); (H.L.); (A.S.)
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12
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Savitskaya A, Masso-Silva J, Haddaoui I, Enany S. Exploring the arsenal of antimicrobial peptides: Mechanisms, diversity, and applications. Biochimie 2023; 214:216-227. [PMID: 37499896 DOI: 10.1016/j.biochi.2023.07.016] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2023] [Revised: 07/09/2023] [Accepted: 07/24/2023] [Indexed: 07/29/2023]
Abstract
Antimicrobial peptides (AMPs) are essential for defence against pathogens in all living organisms and possessed activities against bacteria, fungi, viruses, parasites and even cancer cells. AMPs are short peptides containing 12-100 amino acids conferring a net positive charge and an amphiphilic property in most cases. Although, anionic AMPs also exist. AMPs can be classified based on the types of secondary structures, charge, hydrophobicity, amino acid composition, length, etc. Their mechanism of action usually includes a membrane disruption process through pore formation (three different models have been described, barrel-stave, toroidal or carpet model) but AMPs can also penetrate and impair intracellular functions. Besides their activity against pathogens, they have also shown immunomodulatory properties in complex scenarios through many different interactions. The aim of this review to summarize knowledge about AMP's and discuss the potential application of AMPs as therapeutics, the challenges due to their limitations, including their susceptibility to degradation, the potential generation of AMP resistance, cost, etc. We also discuss the current FDA-approved drugs based on AMPs and strategies to circumvent natural AMPs' limitations.
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Affiliation(s)
- Anna Savitskaya
- Institute of Bioorganic Chemistry of Russian Academy of Science, Moscow, Russian Federation
| | - Jorge Masso-Silva
- Division of Pulmonary, Critical Care, Sleep Medicine and Physiology, University of California San Diego, La Jolla, CA, USA
| | - Imen Haddaoui
- National Research Institute of Rural Engineering, Water and Forestry, University of Carthage, LR Valorization of Unconventional Waters, Ariana, Tunisia
| | - Shymaa Enany
- Microbiology and Immunology Department, Faculty of Pharmacy, Suez Canal University, Ismailia, Egypt; Biomedical Research Department, Armed Force College of Medicine, Cairo, Egypt.
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13
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Li L, Short FL, Hassan KA, Naidu V, Pokhrel A, Nagy SS, Prity FT, Shah BS, Afrin N, Baker S, Parkhill J, Cain AK, Paulsen IT. Systematic analyses identify modes of action of ten clinically relevant biocides and antibiotic antagonism in Acinetobacter baumannii. Nat Microbiol 2023; 8:1995-2005. [PMID: 37814070 DOI: 10.1038/s41564-023-01474-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2019] [Accepted: 08/11/2023] [Indexed: 10/11/2023]
Abstract
Concerns exist that widespread use of antiseptic or disinfectant biocides could contribute to the emergence and spread of multidrug-resistant bacteria. To investigate this, we performed transposon-directed insertion-site sequencing (TraDIS) on the multidrug-resistant pathogen, Acinetobacter baumannii, exposed to a panel of ten structurally diverse and clinically relevant biocides. Multiple gene targets encoding cell envelope or cytoplasmic proteins involved in processes including fatty acid biogenesis, multidrug efflux, the tricarboxylic acid cycle, cell respiration and cell division, were identified to have effects on bacterial fitness upon biocide exposure, suggesting that these compounds may have intracellular targets in addition to their known effects on the cell envelope. As cell respiration genes are required for A. baumannii fitness in biocides, we confirmed that sub-inhibitory concentrations of the biocides that dissipate membrane potential can promote A. baumannii tolerance to antibiotics that act intracellularly. Our results support the concern that residual biocides might promote antibiotic resistance in pathogenic bacteria.
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Affiliation(s)
- Liping Li
- ARC Centre of Excellence in Synthetic Biology, Macquarie University, Sydney, New South Wales, Australia
- School of Natural Sciences, Macquarie University, Sydney, New South Wales, Australia
| | - Francesca L Short
- ARC Centre of Excellence in Synthetic Biology, Macquarie University, Sydney, New South Wales, Australia
- Infection Program and Department of Microbiology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
| | - Karl A Hassan
- ARC Centre of Excellence in Synthetic Biology, Macquarie University, Sydney, New South Wales, Australia
- School of Natural Sciences, Macquarie University, Sydney, New South Wales, Australia
- School of Environmental and Life Sciences, University of Newcastle, Callaghan, New South Wales, Australia
| | - Varsha Naidu
- ARC Centre of Excellence in Synthetic Biology, Macquarie University, Sydney, New South Wales, Australia
- School of Natural Sciences, Macquarie University, Sydney, New South Wales, Australia
- School of Environmental and Life Sciences, University of Newcastle, Callaghan, New South Wales, Australia
| | - Alaska Pokhrel
- ARC Centre of Excellence in Synthetic Biology, Macquarie University, Sydney, New South Wales, Australia
- Australian Institute for Microbiology and Infection (AIMI), University of Technology, Sydney, New South Wales, Australia
| | - Stephanie S Nagy
- School of Natural Sciences, Macquarie University, Sydney, New South Wales, Australia
| | - Farzana T Prity
- ARC Centre of Excellence in Synthetic Biology, Macquarie University, Sydney, New South Wales, Australia
- School of Natural Sciences, Macquarie University, Sydney, New South Wales, Australia
| | - Bhumika S Shah
- ARC Centre of Excellence in Synthetic Biology, Macquarie University, Sydney, New South Wales, Australia
- School of Natural Sciences, Macquarie University, Sydney, New South Wales, Australia
| | - Nusrat Afrin
- School of Natural Sciences, Macquarie University, Sydney, New South Wales, Australia
| | - Stephen Baker
- Cambridge Institute of Therapeutic Immunology and Infectious Disease (CITIID), University of Cambridge, Cambridge, UK
| | - Julian Parkhill
- The Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridge, UK
- Department of Veterinary Medicine, University of Cambridge, Cambridge, UK
| | - Amy K Cain
- ARC Centre of Excellence in Synthetic Biology, Macquarie University, Sydney, New South Wales, Australia.
- School of Natural Sciences, Macquarie University, Sydney, New South Wales, Australia.
| | - Ian T Paulsen
- ARC Centre of Excellence in Synthetic Biology, Macquarie University, Sydney, New South Wales, Australia.
- School of Natural Sciences, Macquarie University, Sydney, New South Wales, Australia.
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14
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Gadar K, de Dios R, Kadeřábková N, Prescott TAK, Mavridou DAI, McCarthy RR. Disrupting iron homeostasis can potentiate colistin activity and overcome colistin resistance mechanisms in Gram-Negative Bacteria. Commun Biol 2023; 6:937. [PMID: 37704838 PMCID: PMC10499790 DOI: 10.1038/s42003-023-05302-2] [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: 01/26/2023] [Accepted: 08/29/2023] [Indexed: 09/15/2023] Open
Abstract
Acinetobacter baumannii is a Gram-negative priority pathogen that can readily overcome antibiotic treatment through a range of intrinsic and acquired resistance mechanisms. Treatment of carbapenem-resistant A. baumannii largely relies on the use of colistin in cases where other treatment options have been exhausted. However, the emergence of resistance against this last-line drug has significantly increased amongst clinical strains. In this study, we identify the phytochemical kaempferol as a potentiator of colistin activity. When administered singularly, kaempferol has no effect on growth but does impact biofilm formation. Nonetheless, co-administration of kaempferol with sub-inhibitory concentrations of colistin exposes bacteria to a metabolic Achilles heel, whereby kaempferol-induced dysregulation of iron homeostasis leads to bacterial killing. We demonstrate that this effect is due to the disruption of Fenton's reaction, and therefore to a lethal build-up of toxic reactive oxygen species in the cell. Furthermore, we show that this vulnerability can be exploited to overcome both intrinsic and acquired colistin resistance in clinical strains of A. baumannii and E. coli in vitro and in the Galleria mellonella model of infection. Overall, our findings provide a proof-of-principle demonstration that targeting iron homeostasis is a promising strategy for enhancing the efficacy of colistin and overcoming colistin-resistant infections.
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Affiliation(s)
- Kavita Gadar
- Biosciences, Department of Life Sciences, College of Health, Medicine and Life Sciences, Brunel University London, Uxbridge, UB8 3PH, UK
| | - Rubén de Dios
- Biosciences, Department of Life Sciences, College of Health, Medicine and Life Sciences, Brunel University London, Uxbridge, UB8 3PH, UK
| | - Nikol Kadeřábková
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX, 78712, USA
| | | | - Despoina A I Mavridou
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX, 78712, USA
- John Ring LaMontagne Centre for Infectious Diseases, The University of Texas at Austin, Austin, TX, 78712, USA
| | - Ronan R McCarthy
- Biosciences, Department of Life Sciences, College of Health, Medicine and Life Sciences, Brunel University London, Uxbridge, UB8 3PH, UK.
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15
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Shenkutie AM, Gebrelibanos D, Yao M, Bedada Hundie G, Chow FWN, Leung PHM. Impairment of novel non-coding small RNA00203 inhibits biofilm formation and reduces biofilm-specific antibiotic resistance in Acinetobacter baumannii. Int J Antimicrob Agents 2023; 62:106889. [PMID: 37315907 DOI: 10.1016/j.ijantimicag.2023.106889] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2023] [Revised: 05/12/2023] [Accepted: 06/09/2023] [Indexed: 06/16/2023]
Abstract
Small RNAs (sRNAs) are post-transcriptional regulators of many biological processes in bacteria, including biofilm formation and antibiotic resistance. The mechanisms by which sRNA regulates the biofilm-specific antibiotic resistance in Acinetobacter baumannii have not been reported to date. This study aimed to investigate the influence of sRNA00203 (53 nucleotides) on biofilm formation, antibiotic susceptibility, and expression of genes associated with biofilm formation and antibiotic resistance. The results showed that deletion of the sRNA00203-encoding gene decreased the biomass of biofilm by 85%. Deletion of the sRNA00203-encoding gene also reduced the minimum biofilm inhibitory concentrations for imipenem and ciprofloxacin 1024- and 128-fold, respectively. Knocking out of sRNA00203 significantly downregulated genes involved in biofilm matrix synthesis (pgaB), efflux pump production (novel00738), lipopolysaccharide biosynthesis (novel00626), preprotein translocase subunit (secA) and the CRP transcriptional regulator. Overall, the suppression of sRNA00203 in an A. baumannii ST1894 strain impaired biofilm formation and sensitized the biofilm cells to imipenem and ciprofloxacin. As sRNA00203 was found to be conserved in A. baumannii, a therapeutic strategy targeting sRNA00203 may be a potential solution for the treatment of biofilm-associated infections caused by A. baumannii. To the best of the authors' knowledge, this is the first study to show the impact of sRNA00203 on biofilm formation and biofilm-specific antibiotic resistance in A. baumannii.
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Affiliation(s)
- Abebe Mekuria Shenkutie
- Department of Health Technology and Informatics, The Hong Kong Polytechnic University, Hong Kong SAR, China; Department of Microbiology, Immunology and Parasitology, St. Paul's Hospital Millennium Medical College, Addis Ababa, Ethiopia
| | - Daniel Gebrelibanos
- Department of Health Technology and Informatics, The Hong Kong Polytechnic University, Hong Kong SAR, China
| | - Mianzhi Yao
- Department of Health Technology and Informatics, The Hong Kong Polytechnic University, Hong Kong SAR, China
| | - Gadissa Bedada Hundie
- Department of Microbiology, Immunology and Parasitology, St. Paul's Hospital Millennium Medical College, Addis Ababa, Ethiopia
| | - Franklin W N Chow
- Department of Health Technology and Informatics, The Hong Kong Polytechnic University, Hong Kong SAR, China
| | - Polly H M Leung
- Department of Health Technology and Informatics, The Hong Kong Polytechnic University, Hong Kong SAR, China.
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16
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Pětrošová H, Mikhael A, Culos S, Giraud-Gatineau A, Gomez AM, Sherman ME, Ernst RK, Cameron CE, Picardeau M, Goodlett DR. Lipid A structural diversity among members of the genus Leptospira. Front Microbiol 2023; 14:1181034. [PMID: 37303810 PMCID: PMC10248169 DOI: 10.3389/fmicb.2023.1181034] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2023] [Accepted: 05/02/2023] [Indexed: 06/13/2023] Open
Abstract
Lipid A is the hydrophobic component of bacterial lipopolysaccharide and an activator of the host immune system. Bacteria modify their lipid A structure to adapt to the surrounding environment and, in some cases, to evade recognition by host immune cells. In this study, lipid A structural diversity within the Leptospira genus was explored. The individual Leptospira species have dramatically different pathogenic potential that ranges from non-infectious to life-threatening disease (leptospirosis). Ten distinct lipid A profiles, denoted L1-L10, were discovered across 31 Leptospira reference species, laying a foundation for lipid A-based molecular typing. Tandem MS analysis revealed structural features of Leptospira membrane lipids that might alter recognition of its lipid A by the host innate immune receptors. Results of this study will aid development of strategies to improve diagnosis and surveillance of leptospirosis, as well as guide functional studies on Leptospira lipid A activity.
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Affiliation(s)
- Helena Pětrošová
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, BC, Canada
- University of Victoria Genome British Columbia Proteomics Center, University of Victoria, Victoria, BC, Canada
| | - Abanoub Mikhael
- University of Victoria Genome British Columbia Proteomics Center, University of Victoria, Victoria, BC, Canada
| | - Sophie Culos
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, BC, Canada
| | | | - Alloysius M. Gomez
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, BC, Canada
| | - Matthew E. Sherman
- Department of Microbial Pathogenesis, University of Maryland, Baltimore, MD, United States
| | - Robert K. Ernst
- Department of Microbial Pathogenesis, University of Maryland, Baltimore, MD, United States
| | - Caroline E. Cameron
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, BC, Canada
- Department of Medicine, Division of Allergy and Infectious Diseases, University of Washington, Seattle, WA, United States
| | - Mathieu Picardeau
- Institut Pasteur, Université Paris Cité, CNRS UMR 6047, Biology of Spirochetes Unit, Paris, France
| | - David R. Goodlett
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, BC, Canada
- University of Victoria Genome British Columbia Proteomics Center, University of Victoria, Victoria, BC, Canada
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17
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Oi KK, Moehle K, Schuster M, Zerbe O. Early Molecular Insights into Thanatin Analogues Binding to A. baumannii LptA. Molecules 2023; 28:4335. [PMID: 37298811 PMCID: PMC10254193 DOI: 10.3390/molecules28114335] [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: 05/04/2023] [Revised: 05/11/2023] [Accepted: 05/12/2023] [Indexed: 06/12/2023] Open
Abstract
The cationic antimicrobial ß-hairpin, thanatin, was recently developed into drug-like analogues active against carbapenem-resistant Enterobacteriaceae (CRE). The analogues represent new antibiotics with a novel mode of action targeting LptA in the periplasm and disrupting LPS transport. The compounds lose antimicrobial efficacy when the sequence identity to E. coli LptA falls below 70%. We wanted to test the thanatin analogues against LptA of a phylogenetic distant organism and investigate the molecular determinants of inactivity. Acinetobacter baumannii (A. baumannii) is a critical Gram-negative pathogen that has gained increasing attention for its multi-drug resistance and hospital burden. A. baumannii LptA shares 28% sequence identity with E. coli LptA and displays an intrinsic resistance to thanatin and thanatin analogues (MIC values > 32 µg/mL) through a mechanism not yet described. We investigated the inactivity further and discovered that these CRE-optimized derivatives can bind to LptA of A. baumannii in vitro, despite the high MIC values. Herein, we present a high-resolution structure of A. baumannii LptAm in complex with a thanatin derivative 7 and binding affinities of selected thanatin derivatives. Together, these data offer structural insights into why thanatin derivatives are inactive against A. baumannii LptA, despite binding events in vitro.
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Affiliation(s)
| | | | | | - Oliver Zerbe
- Department of Chemistry, University of Zurich, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland
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18
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Polymyxin Resistance and Heteroresistance Are Common in Clinical Isolates of Achromobacter Species and Correlate with Modifications of the Lipid A Moiety of Lipopolysaccharide. Microbiol Spectr 2023; 11:e0372922. [PMID: 36519943 PMCID: PMC9927164 DOI: 10.1128/spectrum.03729-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
The Achromobacter genus includes opportunistic pathogens that can cause chronic infections in immunocompromised patients, especially in people with cystic fibrosis (CF). Treatment of Achromobacter infections is complicated by antimicrobial resistance. In this study, a collection of Achromobacter clinical isolates, from CF and non-CF sources, was investigated for polymyxin B (PmB) resistance. Additionally, the effect of PmB challenge in a subset of isolates was examined and the presence of PmB-resistant subpopulations within the isolates was described. Further, chemical and mass spectrometry analyses of the lipid A of Achromobacter clinical isolates enabled the determination of the most common structures and showed that PmB challenge was associated with lipid A modifications that included the addition of glucosamine and palmitoylation and the concomitant loss of the free phosphate at the C-1 position. This study demonstrates that lipid A modifications associated with PmB resistance are prevalent in Achromobacter and that subresistant populations displaying the addition of positively charged residues and additional acyl chains to lipid A can be selected for and isolated from PmB-sensitive Achromobacter clinical isolates. IMPORTANCE Achromobacter species can cause chronic and potentially severe infections in immunocompromised patients, especially in those with cystic fibrosis. Bacteria cannot be eradicated due to Achromobacter's intrinsic multidrug resistance. We report that intrinsic resistance to polymyxin B (PmB), a last-resort antimicrobial peptide used to treat infections by multiresistant bacteria, is prevalent in Achromobacter clinical isolates; many isolates also display increased resistance upon PmB challenge. Analysis of the lipopolysaccharide lipid A moiety of several Achromobacter species reveals a penta-acylated lipid A, which in the PmB-resistant isolates was modified by the incorporation of glucosamine residues, an additional acyl chain, loss of phosphates, and hydroxylation of acyl chains, all of which can enhance PmB resistance in other bacteria. We conclude that PmB resistance, particularly in Achromobacter isolates from chronic respiratory infections, is a common phenomenon, and that Achromobacter lipid A displays modifications that may confer increased resistance to polymyxins and potentially other antimicrobial peptides.
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19
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Sperandeo P, Martorana AM, Zaccaria M, Polissi A. Targeting the LPS export pathway for the development of novel therapeutics. BIOCHIMICA ET BIOPHYSICA ACTA. MOLECULAR CELL RESEARCH 2023; 1870:119406. [PMID: 36473551 DOI: 10.1016/j.bbamcr.2022.119406] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/05/2022] [Revised: 10/14/2022] [Accepted: 11/01/2022] [Indexed: 12/12/2022]
Abstract
The rapid rise of multi-resistant bacteria is a global health threat. This is especially serious for Gram-negative bacteria in which the impermeable outer membrane (OM) acts as a shield against antibiotics. The development of new drugs with novel modes of actions to combat multi-drug resistant pathogens requires the selection of suitable processes to be targeted. The LPS export pathway is an excellent under exploited target for drug development. Indeed, LPS is the major determinant of the OM permeability barrier, and its biogenetic pathway is conserved in most Gram-negatives. Here we describe efforts to identify inhibitors of the multiprotein Lpt system that transports LPS to the cell surface. Despite none of these molecules has been approved for clinical use, they may represent valuable compounds for optimization. Finally, the recent discovery of a link between inhibition of LPS biogenesis and changes in peptidoglycan structure uncovers additional targets to develop novel therapeutic strategies.
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Affiliation(s)
- Paola Sperandeo
- Department of Pharmacological and Biomolecular Sciences, Via Balzaretti 9, 20133 Milano, Italy
| | - Alessandra M Martorana
- Department of Pharmacological and Biomolecular Sciences, Via Balzaretti 9, 20133 Milano, Italy
| | - Marta Zaccaria
- Department of Pharmacological and Biomolecular Sciences, Via Balzaretti 9, 20133 Milano, Italy
| | - Alessandra Polissi
- Department of Pharmacological and Biomolecular Sciences, Via Balzaretti 9, 20133 Milano, Italy.
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20
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Guan XL, Loh JYX, Lizwan M, Chan SCM, Kwan JMC, Lim TP, Koh TH, Hsu LY, Lee BTK. LipidA-IDER to Explore the Global Lipid A Repertoire of Drug-Resistant Gram-Negative Bacteria. Anal Chem 2023; 95:602-611. [PMID: 36599414 PMCID: PMC9850412 DOI: 10.1021/acs.analchem.1c03566] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
With the global emergence of drug-resistant bacteria causing difficult-to-treat infections, there is an urgent need for a tool to facilitate studies on key virulence and antimicrobial resistant factors. Mass spectrometry (MS) has contributed substantially to the elucidation of the structure-function relationships of lipid A, the endotoxic component of lipopolysaccharide which also serves as an important protective barrier against antimicrobials. Here, we present LipidA-IDER, an automated structure annotation tool for system-level scale identification of lipid A from high-resolution tandem mass spectrometry (MS2) data. LipidA-IDER was validated against previously reported structures of lipid A in the reference bacteria, Escherichia coli and Pseudomonas aeruginosa. Using MS2 data of variable quality, we demonstrated LipidA-IDER annotated lipid A with a performance of 71.2% specificity and 70.9% sensitivity, offering greater accuracy than existing lipidomics software. The organism-independent workflow was further applied to a panel of six bacterial species: E. coli and Gram-negative members of ESKAPE pathogens. A comprehensive atlas comprising 188 distinct lipid A species, including remodeling intermediates, was generated and can be integrated with software including MS-DIAL and Metabokit for identification and semiquantitation. Systematic comparison of a pair of polymyxin-sensitive and polymyxin-resistant Acinetobacter baumannii isolated from a human patient unraveled multiple key lipid A structural features of polymyxin resistance within a single analysis. Probing the lipid A landscape of bacteria using LipidA-IDER thus holds immense potential for advancing our understanding of the vast diversity and structural complexity of a key lipid virulence and antimicrobial-resistant factor. LipidA-IDER is freely available at https://github.com/Systems-Biology-Of-Lipid-Metabolism-Lab/LipidA-IDER.
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Affiliation(s)
- Xue Li Guan
- Lee
Kong Chian School of Medicine, Nanyang Technological
University, Singapore 636921, Singapore,. Tel: +65 6592 3957
| | - Johnathan Yi-Xiong Loh
- Lee
Kong Chian School of Medicine, Nanyang Technological
University, Singapore 636921, Singapore
| | - Marco Lizwan
- Lee
Kong Chian School of Medicine, Nanyang Technological
University, Singapore 636921, Singapore
| | - Sharon Cui Mun Chan
- Lee
Kong Chian School of Medicine, Nanyang Technological
University, Singapore 636921, Singapore
| | - Jeric Mun Chung Kwan
- Lee
Kong Chian School of Medicine, Nanyang Technological
University, Singapore 636921, Singapore
| | - Tze Peng Lim
- Department
of Pharmacy, Singapore General Hospital, Singapore 169608, Singapore
| | - Tse Hsien Koh
- Department
of Microbiology, Singapore General Hospital, Singapore 169608, Singapore
| | - Li-Yang Hsu
- Saw Swee
Hock School of Public Health, National University
of Singapore, Singapore 117549, Singapore
| | - Bernett Teck Kwong Lee
- Lee
Kong Chian School of Medicine, Nanyang Technological
University, Singapore 636921, Singapore,Centre
for Biomedical Informatics, Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore 636921, Singapore,Singapore
Immunology Network (SIgN), Agency for Science, Technology and Research (A*STAR), Singapore 138648, Singapore
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21
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Kong X, Chen T, Guo L, Zhou Y, Lu P, Xiao Y. Phenotypic and genomic comparison of dominant and nondominant sequence-type of Acinetobacter baumannii isolated in China. Front Cell Infect Microbiol 2023; 13:1118285. [PMID: 36891157 PMCID: PMC9986592 DOI: 10.3389/fcimb.2023.1118285] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2022] [Accepted: 01/31/2023] [Indexed: 02/22/2023] Open
Abstract
A. baumannii is a common clinical pathogen that often causes pneumonia and bloodstream infections in ICU patients. Sequence types (ST) are used to investigate the distribution and spread of A. baumannii. Biological characteristics such as virulence and resistance may play a role in A. baumannii becoming a specific dominant ST(DST,ST191, ST195 and ST208) strain. To characterize the biological, genetic, and transcriptomic differences between the DST and non-dominant ST(NST,ST462 and ST547,etc.) strains in A. baumannii, we performed several biological experiments and genetic, and transcriptomic analyses. The DST group displayed more resistance ability to desiccation, oxidation, multiple antibiotics, and complement killing than the NST group. However, the latter had higher biofilm formation ability than the former. The genomic analysis showed the DST group exhibited more capsule-related and aminoglycoside-resistant genes. Besides, GO analysis indicated that functions involved in lipid biosynthetic, transport, and the metabolic process were up-regulated in the DST group, while KEGG analysis manifested that the two-component system related to potassium ion transport and pili were down-regulated. In short, resistance to desiccation, oxidation, multiple antibiotics, and serum complement killing are important reasons for the formation of DST. Genes related to capsule synthesis and lipid biosynthesis and metabolism play an important role at the molecular level in the formation of DST.
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Affiliation(s)
- Xiaoyang Kong
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, National Clinical Research Center for Infectious Diseases, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Tao Chen
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, National Clinical Research Center for Infectious Diseases, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Lihua Guo
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, National Clinical Research Center for Infectious Diseases, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Yanzi Zhou
- Department of Rheumatology, Affiliated Hangzhou First People’s Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Ping Lu
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, National Clinical Research Center for Infectious Diseases, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Yonghong Xiao
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, National Clinical Research Center for Infectious Diseases, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
- Jinan Microecological Biomedicine Shandong Laboratory, Jinan, China
- *Correspondence: Yonghong Xiao,
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22
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Hassan M, Flanagan TW, Kharouf N, Bertsch C, Mancino D, Haikel Y. Antimicrobial Proteins: Structure, Molecular Action, and Therapeutic Potential. Pharmaceutics 2022; 15:pharmaceutics15010072. [PMID: 36678702 PMCID: PMC9864823 DOI: 10.3390/pharmaceutics15010072] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2022] [Revised: 12/16/2022] [Accepted: 12/17/2022] [Indexed: 12/28/2022] Open
Abstract
Second- and third-line treatments of patients with antibiotic-resistant infections can have serious side effects, such as organ failure with prolonged care and recovery. As clinical practices such as cancer therapies, chronic disease treatment, and organ transplantation rely on the ability of available antibiotics to fight infection, the increased resistance of microbial pathogens presents a multifaceted, serious public health concern worldwide. The pipeline of traditional antibiotics is exhausted and unable to overcome the continuously developing multi-drug resistance. To that end, the widely observed limitation of clinically utilized antibiotics has prompted researchers to find a clinically relevant alternate antimicrobial strategy. In recent decades, the discovery of antimicrobial peptides (AMPs) as an excellent candidate to overcome antibiotic resistance has received further attention, particularly from scientists, health professionals, and the pharmaceutical industry. Effective AMPs are characterized by a broad spectrum of antimicrobial activities, high pathogen specificity, and low toxicity. In addition to their antimicrobial activity, AMPs have been found to be involved in a variety of biological functions, including immune regulation, angiogenesis, wound healing, and antitumor activity. This review provides a current overview of the structure, molecular action, and therapeutic potential of AMPs.
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Affiliation(s)
- Mohamed Hassan
- Department of Endodontics, Faculty of Dental Medicine, Strasbourg University, 67000 Strasbourg, France
- Department of Biomaterials and Bioengineering, INSERM UMR_S 1121, Biomaterials and Bioengineering, 67000 Strasbourg, France
- Research Laboratory of Surgery-Oncology, Department of Surgery, Tulane University School of Medicine, New Orleans, LA 70112, USA
- Correspondence: ; Tel.: +1-504-339-2671
| | - Thomas W. Flanagan
- Department of Pharmacology and Experimental Therapeutics, LSU Health Sciences Center, New Orleans, LA 70112, USA
| | - Naji Kharouf
- Department of Endodontics, Faculty of Dental Medicine, Strasbourg University, 67000 Strasbourg, France
- Department of Biomaterials and Bioengineering, INSERM UMR_S 1121, Biomaterials and Bioengineering, 67000 Strasbourg, France
| | - Christelle Bertsch
- Department of Endodontics, Faculty of Dental Medicine, Strasbourg University, 67000 Strasbourg, France
- Department of Biomaterials and Bioengineering, INSERM UMR_S 1121, Biomaterials and Bioengineering, 67000 Strasbourg, France
| | - Davide Mancino
- Department of Endodontics, Faculty of Dental Medicine, Strasbourg University, 67000 Strasbourg, France
- Department of Biomaterials and Bioengineering, INSERM UMR_S 1121, Biomaterials and Bioengineering, 67000 Strasbourg, France
| | - Youssef Haikel
- Department of Endodontics, Faculty of Dental Medicine, Strasbourg University, 67000 Strasbourg, France
- Department of Biomaterials and Bioengineering, INSERM UMR_S 1121, Biomaterials and Bioengineering, 67000 Strasbourg, France
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23
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Abstract
This review focuses on nonlytic outer membrane vesicles (OMVs), a subtype of bacterial extracellular vesicles (BEVs) produced by Gram-negative organisms focusing on the mechanisms of their biogenesis, cargo, and function. Throughout, we highlight issues concerning the characterization of OMVs and distinguishing them from other types of BEVs. We also highlight the shortcomings of commonly used methodologies for the study of BEVs that impact the interpretation of their functionality and suggest solutions to standardize protocols for OMV studies.
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Affiliation(s)
| | - Simon R. Carding
- Quadram Institute Bioscience, Norwich, United Kingdom
- Norwich Medical School, University of East Anglia, Norwich, United Kingdom
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24
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Zeczycki TN, Milton ME, Jung D, Thompson RJ, Jaimes FE, Hondros AD, Palethorpe S, Melander C, Cavanagh J. 2-Aminoimidazole Analogs Target PhoP Altering DNA Binding Activity and Affect Outer Membrane Stability in Gram-Negative Bacteria. Biochemistry 2022; 61:2948-2960. [DOI: 10.1021/acs.biochem.2c00560] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Affiliation(s)
- Tonya N. Zeczycki
- Department of Biochemistry and Molecular Biology, Brody School of Medicine, East Carolina University, Greenville, North Carolina27834, United States
| | - Morgan E. Milton
- Department of Biochemistry and Molecular Biology, Brody School of Medicine, East Carolina University, Greenville, North Carolina27834, United States
| | - David Jung
- Agile Sciences Inc., 617 Hutton Street, Raleigh, North Carolina27606, United States
| | - Richele J. Thompson
- Department of Biochemistry and Molecular Biology, Brody School of Medicine, East Carolina University, Greenville, North Carolina27834, United States
| | - Felicia E. Jaimes
- Department of Biochemistry and Molecular Biology, Brody School of Medicine, East Carolina University, Greenville, North Carolina27834, United States
| | - Alexander D. Hondros
- Department of Biochemistry and Molecular Biology, Brody School of Medicine, East Carolina University, Greenville, North Carolina27834, United States
| | - Samantha Palethorpe
- Department of Microbiology and Immunology, Brody School of Medicine, East Carolina University, Greenville, North Carolina27834, United States
| | - Christian Melander
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana46556, United States
| | - John Cavanagh
- Department of Biochemistry and Molecular Biology, Brody School of Medicine, East Carolina University, Greenville, North Carolina27834, United States
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25
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Effects of Sub-Minimum Inhibitory Concentrations of Imipenem and Colistin on Expression of Biofilm-Specific Antibiotic Resistance and Virulence Genes in Acinetobacter baumannii Sequence Type 1894. Int J Mol Sci 2022; 23:ijms232012705. [PMID: 36293559 PMCID: PMC9603859 DOI: 10.3390/ijms232012705] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2022] [Revised: 10/11/2022] [Accepted: 10/18/2022] [Indexed: 12/15/2022] Open
Abstract
Antibiotics at suboptimal doses promote biofilm formation and the development of antibiotic resistance. The underlying molecular mechanisms, however, were not investigated. Here, we report the effects of sub-minimum inhibitory concentrations (sub-MICs) of imipenem and colistin on genes associated with biofilm formation and biofilm-specific antibiotic resistance in a multidrug-tolerant clinical strain of Acinetobacter baumannii Sequence Type (ST) 1894. Comparative transcriptome analysis was performed in untreated biofilm and biofilm treated with sub-MIC doses of imipenem and colistin. RNA sequencing data showed that 78 and 285 genes were differentially expressed in imipenem and colistin-treated biofilm cells, respectively. Among the differentially expressed genes (DEGs), 48 and 197 genes were upregulated exclusively in imipenem and colistin-treated biofilm cells, respectively. The upregulated genes included those encoding matrix synthesis (pgaB), multidrug efflux pump (novel00738), fimbrial proteins, and homoserine lactone synthase (AbaI). Upregulation of biofilm-associated genes might enhance biofilm formation when treated with sub-MICs of antibiotics. The downregulated genes include those encoding DNA gyrase (novel00171), 30S ribosomal protein S20 (novel00584), and ribosome releasing factor (RRF) were downregulated when the biofilm cells were treated with imipenem and colistin. Downregulation of these genes affects protein synthesis, which in turn slows down cell metabolism and makes biofilm cells more tolerant to antibiotics. In this investigation, we also found that 5 of 138 small RNAs (sRNAs) were differentially expressed in biofilm regardless of antibiotic treatment or not. Of these, sRNA00203 showed the highest expression levels in biofilm. sRNAs regulate gene expression and are associated with biofilm formation, which may in turn affect the expression of biofilm-specific antibiotic resistance. In summary, when biofilm cells were exposed to sub-MIC doses of colistin and imipenem, coordinated gene responses result in increased biofilm production, multidrug efflux pump expression, and the slowdown of metabolism, which leads to drug tolerance in biofilm. Targeting antibiotic-induced or repressed biofilm-specific genes represents a new strategy for the development of innovative and effective treatments for biofilm-associated infections caused by A. baumannii.
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26
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Panda G, Dash S, Sahu SK. Harnessing the Role of Bacterial Plasma Membrane Modifications for the Development of Sustainable Membranotropic Phytotherapeutics. MEMBRANES 2022; 12:914. [PMID: 36295673 PMCID: PMC9612325 DOI: 10.3390/membranes12100914] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/14/2022] [Revised: 09/08/2022] [Accepted: 09/19/2022] [Indexed: 06/16/2023]
Abstract
Membrane-targeted molecules such as cationic antimicrobial peptides (CAMPs) are amongst the most advanced group of antibiotics used against drug-resistant bacteria due to their conserved and accessible targets. However, multi-drug-resistant bacteria alter their plasma membrane (PM) lipids, such as lipopolysaccharides (LPS) and phospholipids (PLs), to evade membrane-targeted antibiotics. Investigations reveal that in addition to LPS, the varying composition and spatiotemporal organization of PLs in the bacterial PM are currently being explored as novel drug targets. Additionally, PM proteins such as Mla complex, MPRF, Lpts, lipid II flippase, PL synthases, and PL flippases that maintain PM integrity are the most sought-after targets for development of new-generation drugs. However, most of their structural details and mechanism of action remains elusive. Exploration of the role of bacterial membrane lipidome and proteome in addition to their organization is the key to developing novel membrane-targeted antibiotics. In addition, membranotropic phytochemicals and their synthetic derivatives have gained attractiveness as popular herbal alternatives against bacterial multi-drug resistance. This review provides the current understanding on the role of bacterial PM components on multidrug resistance and their targeting with membranotropic phytochemicals.
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Affiliation(s)
- Gayatree Panda
- Department of Biotechnology, Maharaja Sriram Chandra Bhanjadeo University (Erstwhile: North Orissa University), Baripada 757003, India
| | - Sabyasachi Dash
- Department of Pathology and Laboratory Medicine, Weill Cornell Medicine, New York, NY 10065, USA
| | - Santosh Kumar Sahu
- Department of Biotechnology, Maharaja Sriram Chandra Bhanjadeo University (Erstwhile: North Orissa University), Baripada 757003, India
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27
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Ji F, Huang D, Tan X, Guo Y, Wang Z, Zhou Q, Wang X. Structure analysis of lipid A species in Vibrio parahaemolyticus by constructing mutants lacking multiple secondary acyltransferases of lipid A. Biotechnol Appl Biochem 2022; 70:716-729. [PMID: 35913040 DOI: 10.1002/bab.2393] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2022] [Accepted: 07/24/2022] [Indexed: 11/10/2022]
Abstract
Four secondary acyltransferases of Vibrio parahaemolyticus lipid A encoded by VP_RS00880, VP_RS08405, VP_RS12170 and VP_RS01045 have been identified. In this study, mutants of V. parahaemolyticus were constructed by deleting two, three or four of these genes. The double mutants showed similar growth pattern with the wild type, but the quadruple mutant VPW011 showed significant growth defect at both 37°C and 21°C. Lipid A samples were extracted from these mutants and analyzed by electrospray ionization-mass spectrometry. The double and triple mutants could synthesize hepta- and octa-acylated lipid A species, while the quadruple mutant VPW011could synthesized hexa- and hepta-acylated lipid A. The results suggest that the four secondary acyltransferases could complement each other in V. parahaemolyticus. More importantly, additional secondary acyltransferases of lipid A might exist in V. parahaemolyticus and their activities might be as strong as the four known secondary acyltransferases. The unusual multiple secondary acyltransferases of lipid A might play roles in pathogenicity and antimicrobic resistance of V. parahaemolyticus. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Fan Ji
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, 214122, China.,Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, 214122, China
| | - Danyang Huang
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, 214122, China.,Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, 214122, China
| | - Xin Tan
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, 214122, China.,Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, 214122, China
| | - Yong Guo
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, 214122, China.,Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, 214122, China
| | - Zhen Wang
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, 214122, China.,Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, 214122, China
| | - Qing Zhou
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, 214122, China.,Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, 214122, China
| | - Xiaoyuan Wang
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, 214122, China.,International Joint Laboratory on Food Safety, Jiangnan University, Wuxi, 214122, China.,Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, 214122, China
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Peptidoglycan Recycling Promotes Outer Membrane Integrity and Carbapenem Tolerance in Acinetobacter baumannii. mBio 2022; 13:e0100122. [PMID: 35638738 PMCID: PMC9239154 DOI: 10.1128/mbio.01001-22] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
β-Lactam antibiotics exploit the essentiality of the bacterial cell envelope by perturbing the peptidoglycan layer, typically resulting in rapid lysis and death. Many Gram-negative bacteria do not lyse but instead exhibit "tolerance," the ability to sustain viability in the presence of bactericidal antibiotics for extended periods. Antibiotic tolerance has been implicated in treatment failure and is a stepping-stone in the acquisition of true resistance, and the molecular factors that promote intrinsic tolerance are not well understood. Acinetobacter baumannii is a critical-threat nosocomial pathogen notorious for its ability to rapidly develop multidrug resistance. Carbapenem β-lactam antibiotics (i.e., meropenem) are first-line prescriptions to treat A. baumannii infections, but treatment failure is increasingly prevalent. Meropenem tolerance in Gram-negative pathogens is characterized by morphologically distinct populations of spheroplasts, but the impact of spheroplast formation is not fully understood. Here, we show that susceptible A. baumannii clinical isolates demonstrate tolerance to high-level meropenem treatment, form spheroplasts upon exposure to the antibiotic, and revert to normal growth after antibiotic removal. Using transcriptomics and genetic screens, we show that several genes associated with outer membrane integrity maintenance and efflux promote tolerance, likely by limiting entry into the periplasm. Genes associated with peptidoglycan homeostasis in the periplasm and cytoplasm also answered our screen, and their disruption compromised cell envelope barrier function. Finally, we defined the enzymatic activity of the tolerance determinants penicillin-binding protein 7 (PBP7) and ElsL (a cytoplasmic ld-carboxypeptidase). These data show that outer membrane integrity and peptidoglycan recycling are tightly linked in their contribution to A. baumannii meropenem tolerance. IMPORTANCE Carbapenem treatment failure associated with "superbug" infections has rapidly increased in prevalence, highlighting the urgent need to develop new therapeutic strategies. Antibiotic tolerance can directly lead to treatment failure but has also been shown to promote the acquisition of true resistance within a population. While some studies have addressed mechanisms that promote tolerance, factors that underlie Gram-negative bacterial survival during carbapenem treatment are not well understood. Here, we characterized the role of peptidoglycan recycling in outer membrane integrity maintenance and meropenem tolerance in A. baumannii. These studies suggest that the pathogen limits antibiotic concentrations in the periplasm and highlight physiological processes that could be targeted to improve antimicrobial treatment.
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Havenga B, Reyneke B, Waso-Reyneke M, Ndlovu T, Khan S, Khan W. Biological Control of Acinetobacter baumannii: In Vitro and In Vivo Activity, Limitations, and Combination Therapies. Microorganisms 2022; 10:microorganisms10051052. [PMID: 35630494 PMCID: PMC9147981 DOI: 10.3390/microorganisms10051052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2022] [Revised: 05/16/2022] [Accepted: 05/17/2022] [Indexed: 02/01/2023] Open
Abstract
The survival, proliferation, and epidemic spread of Acinetobacter baumannii (A. baumannii) in hospital settings is associated with several characteristics, including resistance to many commercially available antibiotics as well as the expression of multiple virulence mechanisms. This severely limits therapeutic options, with increased mortality and morbidity rates recorded worldwide. The World Health Organisation, thus, recognises A. baumannii as one of the critical pathogens that need to be prioritised for the development of new antibiotics or treatment. The current review will thus provide a brief overview of the antibiotic resistance and virulence mechanisms associated with A. baumannii’s “persist and resist strategy”. Thereafter, the potential of biological control agents including secondary metabolites such as biosurfactants [lipopeptides (surfactin and serrawettin) and glycolipids (rhamnolipid)] as well as predatory bacteria (Bdellovibrio bacteriovorus) and bacteriophages to directly target A. baumannii, will be discussed in terms of their in vitro and in vivo activity. In addition, limitations and corresponding mitigations strategies will be outlined, including curtailing resistance development using combination therapies, product stabilisation, and large-scale (up-scaling) production.
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Affiliation(s)
- Benjamin Havenga
- Department of Microbiology, Faculty of Science, Stellenbosch University, Private Bag X1, Stellenbosch 7602, South Africa; (B.H.); (B.R.)
| | - Brandon Reyneke
- Department of Microbiology, Faculty of Science, Stellenbosch University, Private Bag X1, Stellenbosch 7602, South Africa; (B.H.); (B.R.)
| | - Monique Waso-Reyneke
- Faculty of Health Sciences, University of Johannesburg, Doornfontein 2028, South Africa; (M.W.-R.); (S.K.)
| | - Thando Ndlovu
- Department of Biological Sciences, Faculty of Science, University of Botswana, Private Bag UB, Gaborone 0022, Botswana;
| | - Sehaam Khan
- Faculty of Health Sciences, University of Johannesburg, Doornfontein 2028, South Africa; (M.W.-R.); (S.K.)
| | - Wesaal Khan
- Department of Microbiology, Faculty of Science, Stellenbosch University, Private Bag X1, Stellenbosch 7602, South Africa; (B.H.); (B.R.)
- Correspondence: ; Tel.: +27-21-808-5804
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30
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Bray AS, Smith RD, Hudson AW, Hernandez GE, Young TM, George HE, Ernst RK, Zafar MA. MgrB-Dependent Colistin Resistance in Klebsiella pneumoniae Is Associated with an Increase in Host-to-Host Transmission. mBio 2022; 13:e0359521. [PMID: 35311534 PMCID: PMC9040857 DOI: 10.1128/mbio.03595-21] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Accepted: 02/08/2022] [Indexed: 12/22/2022] Open
Abstract
Due to its high transmissibility, Klebsiella pneumoniae is one of the leading causes of nosocomial infections. Here, we studied the biological cost of colistin resistance, an antibiotic of last resort, in this opportunistic pathogen using a murine model of gut colonization and transmission. Colistin resistance in K. pneumoniae is commonly the result of the inactivation of the small regulatory protein MgrB. Without a functional MgrB, the two-component system PhoPQ is constitutively active, leading to an increase in lipid A modifications and subsequent colistin resistance. Using an isogenic mgrB deletion mutant (MgrB-), we demonstrate that the mutant's colistin resistance is not associated with a fitness defect under in vitro growth conditions. However, in our murine model of K. pneumoniae gastrointestinal (GI) colonization, the MgrB- colonizes the gut poorly, allowing us to identify a fitness cost. Moreover, the MgrB- mutant has higher survival outside the host compared with the parental strain. We attribute this enhanced survivability to dysregulation of the PhoPQ two-component system and accumulation of the master stress regulator RpoS. The enhanced survival of MgrB- may be critical for its rapid host-to-host transmission observed in our model. Together, our data using multiple clinical isolates demonstrate that MgrB-dependent colistin resistance in K. pneumoniae comes with a biological cost in gut colonization. However, this cost is mitigated by enhanced survival outside the host and consequently increases its host-to-host transmission. Additionally, it underscores the importance of considering the entire life cycle of a pathogen to determine the actual biological cost associated with antibiotic resistance. IMPORTANCE The biological cost associated with colistin resistance in Klebsiella pneumoniae was examined using a murine model of K. pneumoniae gut colonization and fecal-oral transmission. A common mutation resulting in colistin resistance in K. pneumoniae is a loss-of-function mutation of the small regulatory protein MgrB that regulates the two-component system PhoPQ. Even though colistin resistance in K. pneumoniae comes with a fitness defect in gut colonization, it increases bacterial survival outside the host enabling it to transmit more effectively to a new host. The enhanced survival is dependent upon the accumulation of RpoS and dysregulation of the PhoPQ. Hence, our study expands our understanding of the underlying molecular mechanism contributing to the transmission of colistin-resistant K. pneumoniae.
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Affiliation(s)
- Andrew S. Bray
- Department of Microbiology and Immunology, Wake Forest School of Medicine, Winston Salem, North Carolina, USA
| | - Richard D. Smith
- Department of Microbial Pathogenesis, University of Maryland, Baltimore, Baltimore, Maryland, USA
- Department of Pathology, University of Maryland, Baltimore, Baltimore, Maryland, USA
| | - Andrew W. Hudson
- Department of Microbiology and Immunology, Wake Forest School of Medicine, Winston Salem, North Carolina, USA
| | - Giovanna E. Hernandez
- Department of Microbiology and Immunology, Wake Forest School of Medicine, Winston Salem, North Carolina, USA
| | - Taylor M. Young
- Department of Microbiology and Immunology, Wake Forest School of Medicine, Winston Salem, North Carolina, USA
| | | | - Robert K. Ernst
- Department of Microbial Pathogenesis, University of Maryland, Baltimore, Baltimore, Maryland, USA
| | - M. Ammar Zafar
- Department of Microbiology and Immunology, Wake Forest School of Medicine, Winston Salem, North Carolina, USA
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Genome-Wide Identification of Pseudomonas aeruginosa Genes Important for Desiccation Tolerance on Inanimate Surfaces. mSystems 2022; 7:e0011422. [PMID: 35469420 PMCID: PMC9239045 DOI: 10.1128/msystems.00114-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Pseudomonas aeruginosa is an opportunistic pathogen prevalent in the environment and in health care settings. Transmission in the health care setting occurs through human-human interactions and/or contact with contaminated surfaces. Moist surfaces such as respirators, sink and tub drains, and even disinfectants can serve as reservoirs. Dry surfaces such as plastic and stainless steel could also serve as a reservoir but would necessitate some degree of tolerance to desiccation. Using an assay to measure P. aeruginosa tolerance to desiccation on plastic and stainless-steel surfaces, we found that only 0.05 to 0.1% of the desiccated cells could be recovered 24 h postdesiccation. We took advantage of the strong selection imposed by desiccation to identify genes important for tolerance using Tn-seq. A highly saturated Tn-seq library was desiccated on plastic and stainless-steel surfaces. NexGen sequencing of the recovered cells identified 97 genes important for survival. Comparing cells desiccated under low- and high-nutrient conditions allowed for differentiation of genes important for desiccation tolerance. The 53 genes identified in the latter analysis are involved in maintenance of cell envelope integrity, purine and pyrimidine biosynthesis, tricarboxylic acid (TCA) cycle, and the hydrolysis of misfolded proteins. The Tn-seq findings were validated by competition experiments with wild-type (WT) cells and select Tn insertion mutants. Mutants lacking carB and surA demonstrated the largest fitness defects, indicating that pyrimidine biosynthesis and outer membrane integrity are essential for desiccation tolerance. Increased understanding of desiccation tolerance could provide insight into approaches to control environmental reservoirs of P. aeruginosa. IMPORTANCE Health care-associated infections (HAIs) caused by Pseudomonas aeruginosa result in significant morbidity and mortality and are a significant economic burden. Moist environments that promote biofilm formation are an important reservoir for P. aeruginosa. Dry environments may also serve as a reservoir but would require some degree of desiccation tolerance. Here, we took a genome-wide approach to identify genes important for desiccation tolerance on plastic and stainless-steel surfaces. Genes involved in assembly of outer membrane proteins and pyrimidine biosynthesis were particularly important. Strains lacking these functions were unable to tolerate surface desiccation. These findings suggest that inhibitors of these pathways could be used to prevent P. aeruginosa survival on dry surfaces.
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Oda Y, Shapiro MM, Lewis NM, Zhong X, Huse HK, Zhong W, Bruce JE, Manoil C, Harwood CS. CsrA-Controlled Proteins Reveal New Dimensions of Acinetobacter baumannii Desiccation Tolerance. J Bacteriol 2022; 204:e0047921. [PMID: 35285725 PMCID: PMC9017300 DOI: 10.1128/jb.00479-21] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Accepted: 01/24/2022] [Indexed: 12/19/2022] Open
Abstract
Hospital environments are excellent reservoirs for the opportunistic pathogen Acinetobacter baumannii in part because it is exceptionally tolerant to desiccation. We found that relative to other A. baumannii strains, the virulent strain AB5075 was strikingly desiccation resistant at 2% relative humidity (RH), suggesting that it is a good model for studies of the functional basis of this trait. Consistent with results from other A. baumannii strains at 40% RH, we found the global posttranscriptional regulator CsrA to be critically important for desiccation tolerance of AB5075 at 2% RH. Proteomics experiments identified proteins that were differentially present in wild-type and csrA mutant cells. Subsequent analysis of mutants in genes encoding some of these proteins revealed six genes that were required for wild-type levels of desiccation tolerance. These include genes for catalase, a universal stress protein, a hypothetical protein, and a biofilm-associated protein. Two genes of unknown function had very strong desiccation phenotypes, with one of the two genes predicting an intrinsically disordered protein (IDP) that binds to DNA. Intrinsically disordered proteins are widespread in eukaryotes but less so in prokaryotes. Our results suggest there are new mechanisms underlying desiccation tolerance in bacteria and identify several key functions involved. IMPORTANCE Acinetobacter baumannii is found in terrestrial environments but can cause nosocomial infections in very sick patients. A factor that contributes to the prevalence of A. baumannii in hospital settings is that it is intrinsically resistant to dry conditions. Here, we established the virulent strain A. baumannii AB5075 as a model for studies of desiccation tolerance at very low relative humidity. Our results show that this trait depends on two proteins of unknown function, one of which is predicted to be an intrinsically disordered protein. This category of protein is critical for the small animals named tardigrades to survive desiccation. Our results suggest that A. baumannii may have novel strategies to survive desiccation that have not previously been seen in bacteria.
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Affiliation(s)
- Yasuhiro Oda
- Department of Microbiology, University of Washington, Seattle, Washington, USA
| | - Madelyn M. Shapiro
- Seattle Children’s Research Institute, Center for Global Infectious Disease Research, Seattle, Washington, USA
| | - Nathan M. Lewis
- Department of Plant and Microbial Biology, University of Minnesota, St. Paul, Minnesota, USA
| | - Xuefei Zhong
- Analytical Chemistry Group, Regeneron Pharmaceuticals, Tarrytown, New York, USA
| | - Holly K. Huse
- Department of Pathology, Harbor-UCLA Medical Center, Torrance, California, USA
| | - Weizhi Zhong
- Department of Microbiology, University of Washington, Seattle, Washington, USA
| | - James E. Bruce
- Department of Genome Sciences, University of Washington, Seattle, Washington, USA
| | - Colin Manoil
- Department of Genome Sciences, University of Washington, Seattle, Washington, USA
| | - Caroline S. Harwood
- Department of Microbiology, University of Washington, Seattle, Washington, USA
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33
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Valvano MA. Remodelling of the Gram-negative bacterial Kdo 2-lipid A and its functional implications. MICROBIOLOGY (READING, ENGLAND) 2022; 168. [PMID: 35394417 DOI: 10.1099/mic.0.001159] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The lipopolysaccharide (LPS) is a characteristic molecule of the outer leaflet of the Gram-negative bacterial outer membrane, which consists of lipid A, core oligosaccharide, and O antigen. The lipid A is embedded in outer membrane and provides an efficient permeability barrier, which is particularly important to reduce the permeability of antibiotics, toxic cationic metals, and antimicrobial peptides. LPS, an important modulator of innate immune responses ranging from localized inflammation to disseminated sepsis, displays a high level of structural and functional heterogeneity, which arise due to regulated differences in the acylation of the lipid A and the incorporation of non-stoichiometric modifications in lipid A and the core oligosaccharide. This review focuses on the current mechanistic understanding of the synthesis and assembly of the lipid A molecule and its most salient non-stoichiometric modifications.
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Affiliation(s)
- Miguel A Valvano
- Wellcome-Wolfson Institute for Experimental Medicine, Queen's University Belfast, Belfast, BT9 7BL, UK
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34
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Bacterial hydrophilins promote pathogen desiccation tolerance. Cell Host Microbe 2022; 30:975-987.e7. [PMID: 35413266 DOI: 10.1016/j.chom.2022.03.019] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2021] [Revised: 02/14/2022] [Accepted: 03/17/2022] [Indexed: 11/21/2022]
Abstract
Acinetobacter baumannii is a leading cause of hospital-acquired infections, where outbreaks are driven by its ability to persist on surfaces in a desiccated state. Here, we show that A. baumannii causes more virulent pneumonia following desiccation and profile the genetic requirements for desiccation. We find that desiccation tolerance is enhanced upon the disruption of Lon protease, which targets unfolded and aggregated proteins for degradation. Notably, two bacterial hydrophilins, DtpA and DtpB, are transcriptionally upregulated in Δlon via the two-component regulator, BfmR. These proteins, both hydrophilic and intrinsically disordered, promote desiccation tolerance in A. baumannii. Additionally, recombinant DtpA protects purified enzymes from inactivation and improves the desiccation tolerance of a probiotic bacterium when heterologously expressed. These results demonstrate a connection between environmental persistence and pathogenicity in A. baumannii, provide insight into the mechanisms of extreme desiccation tolerance, and reveal potential applications for bacterial hydrophilins in the preservation of protein- and live bacteria-based pharmaceuticals.
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MacDermott-Opeskin HI, Gupta V, O’Mara ML. Lipid-mediated antimicrobial resistance: a phantom menace or a new hope? Biophys Rev 2022; 14:145-162. [PMID: 35251360 PMCID: PMC8880301 DOI: 10.1007/s12551-021-00912-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2021] [Accepted: 11/14/2021] [Indexed: 02/06/2023] Open
Abstract
Abstract The proposition of a post-antimicrobial era is all the more realistic with the continued rise of antimicrobial resistance. The development of new antimicrobials is failing to counter the ever-increasing rates of bacterial antimicrobial resistance. This necessitates novel antimicrobials and drug targets. The bacterial cell membrane is an essential and highly conserved cellular component in bacteria and acts as the primary barrier for entry of antimicrobials into the cell. Although previously under-exploited as an antimicrobial target, the bacterial cell membrane is attractive for the development of novel antimicrobials due to its importance in pathogen viability. Bacterial cell membranes are diverse assemblies of macromolecules built around a central lipid bilayer core. This lipid bilayer governs the overall membrane biophysical properties and function of its membrane-embedded proteins. This mini-review will outline the mechanisms by which the bacterial membrane causes and controls resistance, with a focus on alterations in the membrane lipid composition, chemical modification of constituent lipids, and the efflux of antimicrobials by membrane-embedded efflux systems. Thorough insight into the interplay between membrane-active antimicrobials and lipid-mediated resistance is needed to enable the rational development of new antimicrobials. In particular, the union of computational approaches and experimental techniques for the development of innovative and efficacious membrane-active antimicrobials is explored.
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Affiliation(s)
- Hugo I. MacDermott-Opeskin
- Research School of Chemistry, College of Science, The Australian National University, Canberra, ACT 2601 Australia
| | - Vrinda Gupta
- Research School of Chemistry, College of Science, The Australian National University, Canberra, ACT 2601 Australia
| | - Megan L. O’Mara
- Research School of Chemistry, College of Science, The Australian National University, Canberra, ACT 2601 Australia
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36
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Abstract
Small molecule adjuvants that enhance the activity of established antibiotics represent promising agents in the battle against antibiotic resistance. Adjuvants generally act by inhibiting antibiotic resistance processes, and specifying the process acted on is a critical step in defining an adjuvant's mechanism of action. This step is typically carried out biochemically by identifying molecules that bind adjuvants and then inferring their roles in resistance. Here, we present a complementary genetic strategy based on identifying mutations that both sensitize cells to antibiotic and make them "adjuvant blind." We tested the approach in Acinetobacter baumannii AB5075 using two adjuvants: a well-characterized β-lactamase inhibitor (avibactam) and a compound enhancing outer membrane permeability (aryl 2-aminoimidazole AI-1). The avibactam studies showed that the adjuvant potentiated one β-lactam (ceftazidime) through action on a single β-lactamase (GES-14) and a second (meropenem) by targeting two different enzymes (GES-14 and OXA-23). Mutations impairing disulfide bond formation (DsbAB) also reduced potentiation, possibly by impairing β-lactamase folding. Mutations reducing AI-1 potentiation of canonical Gram-positive antibiotics (vancomycin and clarithromycin) blocked lipooligosaccharide (LOS/LPS) synthesis or its acyl modification. The results indicate that LOS-mediated outer membrane impermeability is targeted by the adjuvant and show the importance of acylation in the resistance. As part of the study, we employed Acinetobacter baylyi as a model to verify the generality of the A. baumannii results and identified the principal resistance genes for ceftazidime, meropenem, vancomycin, and clarithromycin in A. baumannii AB5075. Overall, the work provides a foundation for analyzing adjuvant action using a comprehensive genetic approach. IMPORTANCE One strategy to confront the antibiotic resistance crisis is through the development of adjuvant compounds that increase the efficacy of established drugs. A key step in the development of a natural product adjuvant as a drug is identifying the resistance process it undermines to enhance antibiotic activity. Previous procedures designed to accomplish this have relied on biochemical identification of cell components that bind adjuvant. Here, we present a complementary strategy based on identifying mutations that eliminate adjuvant activity.
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37
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Stapling of Peptides Potentiates: The Antibiotic Treatment of Acinetobacter baumannii In Vivo. Antibiotics (Basel) 2022; 11:antibiotics11020273. [PMID: 35203875 PMCID: PMC8868297 DOI: 10.3390/antibiotics11020273] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Revised: 02/15/2022] [Accepted: 02/18/2022] [Indexed: 11/21/2022] Open
Abstract
The rising incidence of multidrug resistance in Gram-negative bacteria underlines the urgency for novel treatment options. One promising new approach is the synergistic combination of antibiotics with antimicrobial peptides. However, the use of such peptides is not straightforward; they are often sensitive to proteolytic degradation, which greatly limits their clinical potential. One approach to increase stability is to apply a hydrocarbon staple to the antimicrobial peptide, thereby fixing them in an α-helical conformation, which renders them less exposed to proteolytic activity. In this work we applied several different hydrocarbon staples to two previously described peptides shown to act on the outer membrane, L6 and L8, and tested their activity in a zebrafish embryo infection model using a clinical isolate of Acinetobacter baumannii as a pathogen. We show that the introduction of such a hydrocarbon staple to the peptide L8 improves its in vivo potentiating activity on antibiotic treatment, without increasing its in vivo antimicrobial activity, toxicity or hemolytic activity.
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38
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Hamidian M, Maharjan RP, Farrugia DN, Delgado NN, Dinh H, Short FL, Kostoulias X, Peleg AY, Paulsen IT, Cain AK. Genomic and phenotypic analyses of diverse non-clinical Acinetobacter baumannii strains reveals strain-specific virulence and resistance capacity. Microb Genom 2022; 8:000765. [PMID: 35166651 PMCID: PMC8942024 DOI: 10.1099/mgen.0.000765] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2021] [Accepted: 12/15/2021] [Indexed: 12/03/2022] Open
Abstract
Acinetobacter baumannii is a critically important pathogen known for its widespread antibiotic resistance and ability to persist in hospital-associated environments. Whilst the majority of A. baumannii infections are hospital-acquired, infections from outside the hospital have been reported with high mortality. Despite this, little is known about the natural environmental reservoir(s) of A. baumannii and the virulence potential underlying non-clinical strains. Here, we report the complete genome sequences of six diverse strains isolated from environments such as river, soil, and industrial sites around the world. Phylogenetic analyses showed that four of these strains were unrelated to representative nosocomial strains and do not share a monophyletic origin, whereas two had sequence types belonging to the global clone lineages GC1 and GC2. Further, the majority of these strains harboured genes linked to virulence and stress protection in nosocomial strains. These genotypic properties correlated well with in vitro virulence phenotypic assays testing resistance to abiotic stresses, serum survival, and capsule formation. Virulence potential was confirmed in vivo, with most environmental strains able to effectively kill Galleria mellonella greater wax moth larvae. Using phenomic arrays and antibiotic resistance profiling, environmental and nosocomial strains were shown to have similar substrate utilisation patterns although environmental strains were distinctly more sensitive to antibiotics. Taken together, these features of environmental A. baumannii strains suggest the existence of a strain-specific distinct gene pools for niche specific adaptation. Furthermore, environmental strains appear to be equally virulent as contemporary nosocomial strains but remain largely antibiotic sensitive.
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Affiliation(s)
- Mohammad Hamidian
- The iThree institute, University of Technology Sydney, Ultimo, NSW 2007, Australia
| | - Ram P. Maharjan
- ARC Centre of Excellence in Synthetic Biology, Department of Molecular Sciences, Macquarie University, Sydney, NSW 2109, Australia
| | - Daniel N. Farrugia
- ARC Centre of Excellence in Synthetic Biology, Department of Molecular Sciences, Macquarie University, Sydney, NSW 2109, Australia
| | - Natasha N. Delgado
- ARC Centre of Excellence in Synthetic Biology, Department of Molecular Sciences, Macquarie University, Sydney, NSW 2109, Australia
| | - Hue Dinh
- ARC Centre of Excellence in Synthetic Biology, Department of Molecular Sciences, Macquarie University, Sydney, NSW 2109, Australia
| | - Francesca L. Short
- Infection & Immunity Program Monash Biomedicine Discovery Institute, Department of Microbiology, Monash University, Clayton, VIC 3800, Australia
| | - Xenia Kostoulias
- Infection & Immunity Program Monash Biomedicine Discovery Institute, Department of Microbiology, Monash University, Clayton, VIC 3800, Australia
| | - Anton Y. Peleg
- Infection & Immunity Program Monash Biomedicine Discovery Institute, Department of Microbiology, Monash University, Clayton, VIC 3800, Australia
- Department of Infectious Diseases, The Alfred Hospital and Central Clinical School, Monash University, Melbourne, VIC, 3004, Australia
| | - Ian T. Paulsen
- ARC Centre of Excellence in Synthetic Biology, Department of Molecular Sciences, Macquarie University, Sydney, NSW 2109, Australia
| | - Amy K. Cain
- ARC Centre of Excellence in Synthetic Biology, Department of Molecular Sciences, Macquarie University, Sydney, NSW 2109, Australia
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Escobar‐Salom M, Torrens G, Jordana‐Lluch E, Oliver A, Juan C. Mammals' humoral immune proteins and peptides targeting the bacterial envelope: from natural protection to therapeutic applications against multidrug‐resistant
Gram
‐negatives. Biol Rev Camb Philos Soc 2022; 97:1005-1037. [PMID: 35043558 PMCID: PMC9304279 DOI: 10.1111/brv.12830] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Revised: 12/12/2021] [Accepted: 12/15/2021] [Indexed: 12/11/2022]
Abstract
Mammalian innate immunity employs several humoral ‘weapons’ that target the bacterial envelope. The threats posed by the multidrug‐resistant ‘ESKAPE’ Gram‐negative pathogens (Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter spp.) are forcing researchers to explore new therapeutic options, including the use of these immune elements. Here we review bacterial envelope‐targeting (peptidoglycan and/or membrane‐targeting) proteins/peptides of the mammalian immune system that are most likely to have therapeutic applications. Firstly we discuss their general features and protective activity against ESKAPE Gram‐negatives in the host. We then gather, integrate, and discuss recent research on experimental therapeutics harnessing their bactericidal power, based on their exogenous administration and also on the discovery of bacterial and/or host targets that improve the performance of this endogenous immunity, as a novel therapeutic concept. We identify weak points and knowledge gaps in current research in this field and suggest areas for future work to obtain successful envelope‐targeting therapeutic options to tackle the challenge of antimicrobial resistance.
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Affiliation(s)
- María Escobar‐Salom
- Department of Microbiology University Hospital Son Espases‐Health Research Institute of the Balearic Islands (IdISBa) Carretera de Valldemossa 79 Palma Balearic Islands 07010 Spain
| | - Gabriel Torrens
- Department of Microbiology University Hospital Son Espases‐Health Research Institute of the Balearic Islands (IdISBa) Carretera de Valldemossa 79 Palma Balearic Islands 07010 Spain
| | - Elena Jordana‐Lluch
- Department of Microbiology University Hospital Son Espases‐Health Research Institute of the Balearic Islands (IdISBa) Carretera de Valldemossa 79 Palma Balearic Islands 07010 Spain
| | - Antonio Oliver
- Department of Microbiology University Hospital Son Espases‐Health Research Institute of the Balearic Islands (IdISBa) Carretera de Valldemossa 79 Palma Balearic Islands 07010 Spain
| | - Carlos Juan
- Department of Microbiology University Hospital Son Espases‐Health Research Institute of the Balearic Islands (IdISBa) Carretera de Valldemossa 79 Palma Balearic Islands 07010 Spain
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Luong HX, Ngan HD, Thi Phuong HB, Quoc TN, Tung TT. Multiple roles of ribosomal antimicrobial peptides in tackling global antimicrobial resistance. ROYAL SOCIETY OPEN SCIENCE 2022; 9:211583. [PMID: 35116161 PMCID: PMC8790363 DOI: 10.1098/rsos.211583] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Accepted: 12/20/2021] [Indexed: 05/03/2023]
Abstract
In the last century, conventional antibiotics have played a significant role in global healthcare. Antibiotics support the body in controlling bacterial infection and simultaneously increase the tendency of drug resistance. Consequently, there is a severe concern regarding the regression of the antibiotic era. Despite the use of antibiotics, host defence systems are vital in fighting infectious diseases. In fact, the expression of ribosomal antimicrobial peptides (AMPs) has been crucial in the evolution of innate host defences and has been irreplaceable to date. Therefore, this valuable source is considered to have great potential in tackling the antimicrobial resistance (AMR) crisis. Furthermore, the possibility of bacterial resistance to AMPs has been intensively investigated. Here, we summarize all aspects related to the multiple applications of ribosomal AMPs and their derivatives in combating AMR.
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Affiliation(s)
- Huy Xuan Luong
- Faculty of Pharmacy, PHENIKAA University, Hanoi 12116, Vietnam
- PHENIKAA Institute for Advanced Study (PIAS), PHENIKAA University, Hanoi 12116, Vietnam
| | | | | | - Thang Nguyen Quoc
- Nuclear Medicine Unit, Vinmec Healthcare System, Hanoi 10000, Vietnam
| | - Truong Thanh Tung
- Faculty of Pharmacy, PHENIKAA University, Hanoi 12116, Vietnam
- PHENIKAA Institute for Advanced Study (PIAS), PHENIKAA University, Hanoi 12116, Vietnam
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Tao Y, Duma L, Rossez Y. Galleria mellonella as a Good Model to Study Acinetobacter baumannii Pathogenesis. Pathogens 2021; 10:1483. [PMID: 34832638 PMCID: PMC8623143 DOI: 10.3390/pathogens10111483] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Revised: 11/08/2021] [Accepted: 11/10/2021] [Indexed: 12/29/2022] Open
Abstract
The invertebrate model, Galleria mellonella, has been widely used to study host-pathogen interactions due to its cheapness, ease of handling, and similar mammalian innate immune system. G. mellonella larvae have been proven to be useful and a reliable model for analyzing pathogenesis mechanisms of multidrug resistant Acinetobacter baumannii, an opportunistic pathogen difficult to kill. This review describes the detailed experimental design of G. mellonella/A. baumannii models, and provides a comprehensive comparison of various virulence factors and therapy strategies using the G. mellonella host. These investigations highlight the importance of this host-pathogen model for in vivo pathogen virulence studies. On the long term, further development of the G. mellonella/A. baumannii model will offer promising insights for clinical treatments of A. baumannii infection.
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Affiliation(s)
- Ye Tao
- Université de Technologie de Compiègne, UPJV, UMR CNRS 7025, Enzyme and Cell Engineering, Centre de Recherche Royallieu–CS 60 319 , 60203 Compiègne, France; (Y.T.); (L.D.)
| | - Luminita Duma
- Université de Technologie de Compiègne, UPJV, UMR CNRS 7025, Enzyme and Cell Engineering, Centre de Recherche Royallieu–CS 60 319 , 60203 Compiègne, France; (Y.T.); (L.D.)
- Université de Reims Champagne-Ardenne, CNRS, ICMR UMR 7312, 51097 Reims, France
| | - Yannick Rossez
- Université Lille, CNRS, UMR 8576-UGSF-Unité de Glycobiologie Structurale et Fonctionnelle, F-59000 Lille, France
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Yoon EJ, Kim HS, Woo H, Choi YJ, Won D, Choi JR, Kim YA, Jeong SH. Trajectory of genetic alterations associated with colistin resistance in Acinetobacter baumannii during an in-hospital outbreak of infection. J Antimicrob Chemother 2021; 77:69-73. [PMID: 34609499 DOI: 10.1093/jac/dkab363] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Accepted: 09/06/2021] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND As carbapenem-resistant Acinetobacter baumannii is dominant in clinical settings, the old polymyxin antibiotic colistin has been revived as a therapeutic option. The development of colistin resistance during treatment is becoming a growing concern. OBJECTIVES To access low- to mid-level colistin-resistant A. baumannii blood isolates recovered from an outbreak in a tertiary care hospital from a national antimicrobial surveillance study. METHODS The entire bacterial genome was sequenced through long-read sequencing methodology. Quantitative RT-PCR was carried out to determine the level of gene expression. Relative growth rates were determined to estimate fitness costs of each isolate caused by the genetic alterations. RESULTS The A. baumannii isolates belonged to global clone 2 harbouring two intrinsic phosphoethanolamine transferases. Cumulative alterations continuing the colistin resistance were observed. PmrC overproduction caused by the PmrBA226T alteration was identified in A. baumannii isolates with low-level colistin resistance and an additional PmrCR109H substitution led to mid-level colistin resistance. Truncation of the PmrC enzyme by insertion of ISAba59 was compensated by ISAba10-mediated overproduction of EptA and, in the last isolate, the complete PmrAB two-component regulatory system was eliminated to restore the biological cost of the bacterial host. CONCLUSIONS During the in-hospital outbreak, a trajectory of genetic modification in colistin-resistant A. baumannii isolates was observed for survival in the harsh conditions imposed by life-threatening drugs with the clear purpose of maintaining drug resistance above a certain level with a reasonable fitness cost.
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Affiliation(s)
- Eun-Jeong Yoon
- Department of Laboratory Medicine, Yonsei University College of Medicine, Seoul, South Korea.,Research Institute of Bacterial Resistance, Yonsei University College of Medicine, Seoul, South Korea
| | - Hyun Soo Kim
- Department of Laboratory Medicine, Hallym University Dongtan Sacred Heart Hospital, Hallym University College of Medicine, Hwaseong, South Korea
| | - Heungjeong Woo
- Department of Infectious Diseases, Hallym University Dongtan Sacred Heart Hospital, Hallym University College of Medicine, Hwaseong, South Korea
| | - You Jeong Choi
- Department of Laboratory Medicine, Yonsei University College of Medicine, Seoul, South Korea.,Research Institute of Bacterial Resistance, Yonsei University College of Medicine, Seoul, South Korea
| | - Dongju Won
- Department of Laboratory Medicine, Yonsei University College of Medicine, Seoul, South Korea
| | - Jong Rak Choi
- Department of Laboratory Medicine, Yonsei University College of Medicine, Seoul, South Korea
| | - Young Ah Kim
- Department of Laboratory Medicine, National Health Insurance Service Ilsan Hospital, Goyang, South Korea
| | - Seok Hoon Jeong
- Department of Laboratory Medicine, Yonsei University College of Medicine, Seoul, South Korea.,Research Institute of Bacterial Resistance, Yonsei University College of Medicine, Seoul, South Korea
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43
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Heiles S. Advanced tandem mass spectrometry in metabolomics and lipidomics-methods and applications. Anal Bioanal Chem 2021; 413:5927-5948. [PMID: 34142202 PMCID: PMC8440309 DOI: 10.1007/s00216-021-03425-1] [Citation(s) in RCA: 56] [Impact Index Per Article: 18.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2021] [Revised: 05/11/2021] [Accepted: 05/19/2021] [Indexed: 12/11/2022]
Abstract
Metabolomics and lipidomics are new drivers of the omics era as molecular signatures and selected analytes allow phenotypic characterization and serve as biomarkers, respectively. The growing capabilities of untargeted and targeted workflows, which primarily rely on mass spectrometric platforms, enable extensive charting or identification of bioactive metabolites and lipids. Structural annotation of these compounds is key in order to link specific molecular entities to defined biochemical functions or phenotypes. Tandem mass spectrometry (MS), first and foremost collision-induced dissociation (CID), is the method of choice to unveil structural details of metabolites and lipids. But CID fragment ions are often not sufficient to fully characterize analytes. Therefore, recent years have seen a surge in alternative tandem MS methodologies that aim to offer full structural characterization of metabolites and lipids. In this article, principles, capabilities, drawbacks, and first applications of these "advanced tandem mass spectrometry" strategies will be critically reviewed. This includes tandem MS methods that are based on electrons, photons, and ion/molecule, as well as ion/ion reactions, combining tandem MS with concepts from optical spectroscopy and making use of derivatization strategies. In the final sections of this review, the first applications of these methodologies in combination with liquid chromatography or mass spectrometry imaging are highlighted and future perspectives for research in metabolomics and lipidomics are discussed.
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Affiliation(s)
- Sven Heiles
- Institute of Inorganic and Analytical Chemistry, Justus Liebig University Giessen, Heinrich Buff Ring 17, 35392, Giessen, Germany.
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Gedefie A, Demsis W, Ashagrie M, Kassa Y, Tesfaye M, Tilahun M, Bisetegn H, Sahle Z. Acinetobacter baumannii Biofilm Formation and Its Role in Disease Pathogenesis: A Review. Infect Drug Resist 2021; 14:3711-3719. [PMID: 34531666 PMCID: PMC8439624 DOI: 10.2147/idr.s332051] [Citation(s) in RCA: 82] [Impact Index Per Article: 27.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2021] [Accepted: 09/02/2021] [Indexed: 01/01/2023] Open
Abstract
Acinetobacter species, particularly Acinetobacter baumannii, is the first pathogen on the critical priority list of pathogens for novel antibiotics to become a "red-alert" human pathogen. Acinetobacter baumannii is an emerging global antibiotic-resistant gram-negative bacteria that most typically causes biofilm-associated infections such as ventilator-associated pneumonia and catheter-related infection, both of which are resistant to antibiotic therapy. A. baumannii's capacity to develop antibiotic resistance mechanisms allows the organism to thrive in hospital settings, facilitating the global spread of multidrug-resistant strains. Although Acinetobacter infections are quickly expanding throughout hospital environments around the world, the highest concentration of infections occurs in intensive care units (ICUs). Biofilms are populations of bacteria on biotic or abiotic surfaces that are encased in the extracellular matrix and play a crucial role in pathogenesis, making treatment options more difficult. Even though a variety of biological and environmental elements are involved in the production of A. baumannii biofilms, glucose is the most important component. Biofilm-mediated A. baumannii infections are the most common type of A. baumannii infection associated with medical equipment, and they are extremely difficult to treat. As a result, health care workers (HCWs) should focus on infection prevention and safety actions to avoid A. baumannii biofilm-related infections caused by medical devices, and they should be very selective when using treatments in combination with anti-biofilms. Therefore, this review discusses biofilm formation in A. baumannii, its role in disease pathogenesis, and its antimicrobial resistance mechanism.
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Affiliation(s)
- Alemu Gedefie
- Department of Medical Laboratory Sciences, College of Medicine and Health Science, Wollo University, Dessie, Ethiopia
| | - Wondmagegn Demsis
- Department of Medical Laboratory Sciences, College of Medicine and Health Science, Wollo University, Dessie, Ethiopia
| | - Melaku Ashagrie
- Department of Medical Laboratory Sciences, College of Medicine and Health Science, Wollo University, Dessie, Ethiopia
| | - Yeshimebet Kassa
- Department of Medical Laboratory Sciences, College of Medicine and Health Science, Wollo University, Dessie, Ethiopia
| | - Melkam Tesfaye
- Department of Medical Laboratory Sciences, College of Medicine and Health Science, Wollo University, Dessie, Ethiopia
| | - Mihret Tilahun
- Department of Medical Laboratory Sciences, College of Medicine and Health Science, Wollo University, Dessie, Ethiopia
| | - Habtye Bisetegn
- Department of Medical Laboratory Sciences, College of Medicine and Health Science, Wollo University, Dessie, Ethiopia
| | - Zenawork Sahle
- Department of Medical Laboratory Sciences, Debre Birhan Health Science College, Debre Birhan, Ethiopia
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Crippen CS, Glushka J, Vinogradov E, Szymanski CM. Trehalose-deficient Acinetobacter baumannii exhibits reduced virulence by losing capsular polysaccharide and altering membrane integrity. Glycobiology 2021; 31:1520-1530. [PMID: 34473830 DOI: 10.1093/glycob/cwab096] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Revised: 08/14/2021] [Accepted: 08/15/2021] [Indexed: 12/20/2022] Open
Abstract
A. baumannii has become the leading cause of bacterial nosocomial infections in part due to its ability to resist desiccation, disinfection and antibiotics. Several factors contribute to the tenacity and virulence of this pathogen, including production of a broad range of surface glycoconjugates, secretory systems and efflux pumps. We became interested in examining the importance of trehalose in A. baumannii after comparing intact bacterial cells by high resolution magic angle spinning NMR and noting high levels of this disaccharide obscuring all other resonances in the spectrum. Since this was observed under normal growth conditions, we speculated that trehalose must serve additional functions beyond osmolyte homeostasis. Using the virulent isolate A. baumannii AB5075 and mutants in the trehalose synthesis pathway, ∆otsA and ∆otsB, we found that the trehalose-deficient ∆otsA showed increased sensitivity to desiccation, colistin, serum complement and peripheral blood mononuclear cells while trehalose-6-phosphate producing ∆otsB behaved similar to the wildtype. The ∆otsA mutant also demonstrated increased membrane permeability and loss of capsular polysaccharide. These findings demonstrate that trehalose deficiency leads to loss of virulence in A. baumannii AB5075.
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Affiliation(s)
- Clay S Crippen
- Department of Microbiology, University of Georgia, Athens, GA, USA.,Complex Carbohydrate Research Center, University of Georgia, Athens, GA, USA
| | - John Glushka
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA, USA
| | - Evgeny Vinogradov
- Human Health Therapeutics, National Research Council, Ottawa, ON, Canada
| | - Christine M Szymanski
- Department of Microbiology, University of Georgia, Athens, GA, USA.,Complex Carbohydrate Research Center, University of Georgia, Athens, GA, USA
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Homeoviscous Adaptation of the Acinetobacter baumannii Outer Membrane: Alteration of Lipooligosaccharide Structure during Cold Stress. mBio 2021; 12:e0129521. [PMID: 34425709 PMCID: PMC8406137 DOI: 10.1128/mbio.01295-21] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
To maintain optimal membrane dynamics, cells from all domains of life must acclimate to various environmental signals in a process referred to as homeoviscous adaptation. Alteration of the lipid composition is critical for maintaining membrane fluidity, permeability of the lipid bilayer, and protein function under diverse conditions. It is well documented, for example, that glycerophospholipid content varies substantially in both Gram-negative and Gram-positive bacteria with changes in growth temperature. However, in the case of Gram-negative bacteria, far less is known concerning structural changes in lipopolysaccharide (LPS) or lipooligosaccharide (LOS) during temperature shifts. LPS/LOS is anchored at the cell surface by the highly conserved lipid A domain and localized in the outer leaflet of the outer membrane. Here, we identified a novel acyltransferase, termed LpxS, involved in the synthesis of the lipid A domain of Acinetobacter baumannii. A. baumannii is a significant, multidrug-resistant, opportunistic pathogen that is particularly difficult to clear from health care settings because of its ability to survive under diverse conditions. LpxS transfers an octanoate (C8:0) fatty acid, the shortest known secondary acyl chain reported to date, replacing a C12:0 fatty acid at the 2' position of lipid A. Expression of LpxS was highly upregulated under cold conditions and likely increases membrane fluidity. Furthermore, incorporation of a C8:0 acyl chain under cold conditions increased the effectiveness of the outer membrane permeability barrier. LpxS orthologs are found in several Acinetobacter species and may represent a common mechanism for adaptation to cold temperatures in these organisms. IMPORTANCE To maintain cellular fitness, the composition of biological membranes must change in response to shifts in temperature or other stresses. This process, known as homeoviscous adaptation, allows for maintenance of optimal fluidity and membrane permeability. Here, we describe an enzyme that alters the fatty acid content of A. baumannii LOS, a major structural feature and key component of the bacterial outer membrane. Although much is known regarding how glycerophospholipids are altered during temperature shifts, our understanding of LOS or LPS alterations under these conditions is lacking. Our work identifies a cold adaptation mechanism in A. baumannii, a highly adaptable and multidrug-resistant pathogen.
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Interest of Homodialkyl Neamine Derivatives against Resistant P. aeruginosa, E. coli, and β-Lactamases-Producing Bacteria-Effect of Alkyl Chain Length on the Interaction with LPS. Int J Mol Sci 2021; 22:ijms22168707. [PMID: 34445410 PMCID: PMC8396045 DOI: 10.3390/ijms22168707] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Revised: 07/29/2021] [Accepted: 08/07/2021] [Indexed: 11/24/2022] Open
Abstract
Development of novel therapeutics to treat antibiotic-resistant infections, especially those caused by ESKAPE pathogens, is urgent. One of the most critical pathogens is P. aeruginosa, which is able to develop a large number of factors associated with antibiotic resistance, including high level of impermeability. Gram-negative bacteria are protected from the environment by an asymmetric Outer Membrane primarily composed of lipopolysaccharides (LPS) at the outer leaflet and phospholipids in the inner leaflet. Based on a large hemi-synthesis program focusing on amphiphilic aminoglycoside derivatives, we extend the antimicrobial activity of 3′,6-dinonyl neamine and its branched isomer, 3′,6-di(dimethyloctyl) neamine on clinical P. aeruginosa, ESBL, and carbapenemase strains. We also investigated the capacity of 3′,6-homodialkyl neamine derivatives carrying different alkyl chains (C7–C11) to interact with LPS and alter membrane permeability. 3′,6-Dinonyl neamine and its branched isomer, 3′,6-di(dimethyloctyl) neamine showed low MICs on clinical P. aeruginosa, ESBL, and carbapenemase strains with no MIC increase for long-duration incubation. In contrast from what was observed for membrane permeability, length of alkyl chains was critical for the capacity of 3′,6-homodialkyl neamine derivatives to bind to LPS. We demonstrated the high antibacterial potential of the amphiphilic neamine derivatives in the fight against ESKAPE pathogens and pointed out some particular characteristics making the 3′,6-dinonyl- and 3′,6-di(dimethyloctyl)-neamine derivatives the best candidates for further development.
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48
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Alfei S, Caviglia D, Piatti G, Zuccari G, Schito AM. Bactericidal Activity of a Self-Biodegradable Lysine-Containing Dendrimer against Clinical Isolates of Acinetobacter Genus. Int J Mol Sci 2021; 22:7274. [PMID: 34298891 PMCID: PMC8306826 DOI: 10.3390/ijms22147274] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2021] [Revised: 07/03/2021] [Accepted: 07/05/2021] [Indexed: 12/19/2022] Open
Abstract
The genus Acinetobacter consists of Gram-negative obligate aerobic pathogens, including clinically relevant species, such as A. baumannii, which frequently cause hospital infections, affecting debilitated patients. The growing resistance to antimicrobial therapies shown by A. baumannii is reaching unacceptable levels in clinical practice, and there is growing concern that the serious conditions it causes may soon become incurable. New therapeutic possibilities are, therefore, urgently needed to circumvent this important problem. Synthetic cationic macromolecules, such as cationic antimicrobial peptides (AMPs), which act as membrane disrupters, could find application in these conditions. A lysine-modified cationic polyester-based dendrimer (G5-PDK), capable of electrostatically interacting with bacterial surfaces as AMPs do, has been synthesized and characterized here. Given its chemical structure, similar to that of a fifth-generation lysine containing dendrimer (G5K) with a different core, and previously found inactive against Gram-positive bacterial species and Enterobacteriaceae, the new G5-PDK was also ineffective on the species mentioned above. In contrast, it showed minimum inhibitory concentration values (MICs) lower than reported for several AMPs and other synthetic cationic compounds on Acinetobacter genus (3.2-12.7 µM). Time-kill experiments on A. baumannii, A. pittii, and A. ursingii ascertained the rapid bactericidal effects of G5-PDK, while subsequent bacterial regrowth supported its self-biodegradability.
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Affiliation(s)
- Silvana Alfei
- Department of Pharmacy, University of Genoa, Viale Cembrano, 16148 Genoa, Italy;
| | - Debora Caviglia
- Department of Surgical Sciences and Integrated Diagnostics (DISC), University of Genoa, Viale Benedetto XV, 6, 16132 Genova, Italy; (D.C.); (G.P.); (A.M.S.)
| | - Gabriella Piatti
- Department of Surgical Sciences and Integrated Diagnostics (DISC), University of Genoa, Viale Benedetto XV, 6, 16132 Genova, Italy; (D.C.); (G.P.); (A.M.S.)
| | - Guendalina Zuccari
- Department of Pharmacy, University of Genoa, Viale Cembrano, 16148 Genoa, Italy;
| | - Anna Maria Schito
- Department of Surgical Sciences and Integrated Diagnostics (DISC), University of Genoa, Viale Benedetto XV, 6, 16132 Genova, Italy; (D.C.); (G.P.); (A.M.S.)
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Harvey DJ. ANALYSIS OF CARBOHYDRATES AND GLYCOCONJUGATES BY MATRIX-ASSISTED LASER DESORPTION/IONIZATION MASS SPECTROMETRY: AN UPDATE FOR 2015-2016. MASS SPECTROMETRY REVIEWS 2021; 40:408-565. [PMID: 33725404 DOI: 10.1002/mas.21651] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Accepted: 07/24/2020] [Indexed: 06/12/2023]
Abstract
This review is the ninth update of the original article published in 1999 on the application of matrix-assisted laser desorption/ionization (MALDI) mass spectrometry to the analysis of carbohydrates and glycoconjugates and brings coverage of the literature to the end of 2016. Also included are papers that describe methods appropriate to analysis by MALDI, such as sample preparation techniques, even though the ionization method is not MALDI. Topics covered in the first part of the review include general aspects such as theory of the MALDI process, matrices, derivatization, MALDI imaging, fragmentation and arrays. The second part of the review is devoted to applications to various structural types such as oligo- and poly-saccharides, glycoproteins, glycolipids, glycosides and biopharmaceuticals. Much of this material is presented in tabular form. The third part of the review covers medical and industrial applications of the technique, studies of enzyme reactions and applications to chemical synthesis. The reported work shows increasing use of combined new techniques such as ion mobility and the enormous impact that MALDI imaging is having. MALDI, although invented over 30 years ago is still an ideal technique for carbohydrate analysis and advancements in the technique and range of applications show no sign of deminishing. © 2020 Wiley Periodicals, Inc.
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Affiliation(s)
- David J Harvey
- Nuffield Department of Medicine, Target Discovery Institute, University of Oxford, Roosevelt Drive, Oxford, OX3 7FZ, United Kingdom
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50
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Kazi MI, Perry BW, Card DC, Schargel RD, Ali HB, Obuekwe VC, Sapkota M, Kang KN, Pellegrino MW, Greenberg DE, Castoe TA, Boll JM. Discovery and characterization of New Delhi metallo-β-lactamase-1 inhibitor peptides that potentiate meropenem-dependent killing of carbapenemase-producing Enterobacteriaceae. J Antimicrob Chemother 2021; 75:2843-2851. [PMID: 32591801 DOI: 10.1093/jac/dkaa242] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2020] [Revised: 04/20/2020] [Accepted: 05/06/2020] [Indexed: 12/13/2022] Open
Abstract
OBJECTIVES Metallo-β-lactamases (MBLs) are an emerging class of antimicrobial resistance enzymes that degrade β-lactam antibiotics, including last-resort carbapenems. Infections caused by carbapenemase-producing Enterobacteriaceae (CPE) are increasingly prevalent, but treatment options are limited. While several serine-dependent β-lactamase inhibitors are formulated with commonly prescribed β-lactams, no MBL inhibitors are currently approved for combinatorial therapies. New compounds that target MBLs to restore carbapenem activity against CPE are therefore urgently needed. Herein we identified and characterized novel synthetic peptide inhibitors that bound to and inhibited NDM-1, which is an emerging β-lactam resistance mechanism in CPE. METHODS We leveraged Surface Localized Antimicrobial displaY (SLAY) to identify and characterize peptides that inhibit NDM-1, which is a primary carbapenem resistance mechanism in CPE. Lead inhibitor sequences were chemically synthesized and MBCs and MICs were calculated in the presence/absence of carbapenems. Kinetic analysis with recombinant NDM-1 and select peptides tested direct binding and supported NDM-1 inhibitor mechanisms of action. Inhibitors were also tested for cytotoxicity. RESULTS We identified approximately 1700 sequences that potentiated carbapenem-dependent killing against NDM-1 Escherichia coli. Several also enhanced meropenem-dependent killing of other CPE. Biochemical characterization of a subset indicated the peptides penetrated the bacterial periplasm and directly bound NDM-1 to inhibit enzymatic activity. Additionally, each demonstrated minimal haemolysis and cytotoxicity against mammalian cell lines. CONCLUSIONS Our approach advances a molecular platform for antimicrobial discovery, which complements the growing need for alternative antimicrobials. We also discovered lead NDM-1 inhibitors, which serve as a starting point for further chemical optimization.
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Affiliation(s)
- Misha I Kazi
- Department of Biology, University of Texas at Arlington, Arlington, TX, USA
| | - Blair W Perry
- Department of Biology, University of Texas at Arlington, Arlington, TX, USA
| | - Daren C Card
- Department of Biology, University of Texas at Arlington, Arlington, TX, USA
| | - Richard D Schargel
- Department of Biology, University of Texas at Arlington, Arlington, TX, USA
| | - Hana B Ali
- Department of Biology, University of Texas at Arlington, Arlington, TX, USA
| | - Victor C Obuekwe
- Department of Biology, University of Texas at Arlington, Arlington, TX, USA.,Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Madhab Sapkota
- Department of Biology, University of Texas at Arlington, Arlington, TX, USA
| | - Katie N Kang
- Department of Biology, University of Texas at Arlington, Arlington, TX, USA
| | - Mark W Pellegrino
- Department of Biology, University of Texas at Arlington, Arlington, TX, USA
| | - David E Greenberg
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA.,Department of Microbiology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Todd A Castoe
- Department of Biology, University of Texas at Arlington, Arlington, TX, USA
| | - Joseph M Boll
- Department of Biology, University of Texas at Arlington, Arlington, TX, USA
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