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Tang W, Osborne J, Dortet L, Larrouy-Maumus G. A whole cell-based Matrix-assisted laser desorption/ionization mass spectrometry lipidomic assay for the discovery of compounds that target lipid a modifications. Front Microbiol 2023; 14:1156795. [PMID: 37138618 PMCID: PMC10149749 DOI: 10.3389/fmicb.2023.1156795] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Accepted: 03/28/2023] [Indexed: 05/05/2023] Open
Abstract
Introduction Matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS) is a powerful analytical technique that has been applied to a wide variety of applications ranging from proteomics to clinical diagnostics. One such application is its use as a tool for discovery assays, such as monitoring the inhibition of purified proteins. With the global threat from antimicrobial-resistant (AMR) bacteria, new and innovative solutions are required to identify new molecules that could revert bacterial resistance and/or target virulence factors. Here, we used a whole cell-based MALDI-TOF lipidomic assay using a routine MALDI Biotyper Sirius system operating in linear negative ion mode combined with the MBT Lipid Xtract kit to discover molecules targeting bacteria that are resistant to polymyxins, which are considered last-resort antibiotics. Methods A library of 1200 natural compounds was tested against an E. coli strain expressing mcr-1, which is known to modify lipid A by adding phosphoethanolamine (pETN), making the strain resistant to colistin. Results and Discussion Using this approach, we identified 8 compounds that led to a decrease in this lipid A modification by MCR-1 and could potentially be employed to revert resistance. Taken together, as-proof-of-principle, the data we report here represent a new workflow based on the analysis of bacterial lipid A by routine MALDI-TOF for the discovery of inhibitors that could target bacterial viability and/or virulence.
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Affiliation(s)
- Wenhao Tang
- Faculty of Natural Sciences, Department of Mathematics, Imperial College London, London, United Kingdom
| | | | - Laurent Dortet
- Department of Bacteriology-Hygiene, Bicêtre Hospital, Assistance Publique–Hôpitaux de Paris, Le Kremlin-Bicêtre, France
| | - Gerald Larrouy-Maumus
- Faculty of Natural Sciences, Department of Life Sciences, Centre for Bacterial Resistance Biology, Imperial College London, London, United Kingdom
- *Correspondence: Gerald Larrouy-Maumus,
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Harvey DJ. Analysis of carbohydrates and glycoconjugates by matrix-assisted laser desorption/ionization mass spectrometry: An update for 2019-2020. Mass Spectrom Rev 2022:e21806. [PMID: 36468275 DOI: 10.1002/mas.21806] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
This review is the tenth 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 2020. 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. The review is basically divided into three sections: (1) general aspects such as theory of the MALDI process, matrices, derivatization, MALDI imaging, fragmentation, quantification and the use of arrays. (2) Applications to various structural types such as oligo- and polysaccharides, glycoproteins, glycolipids, glycosides and biopharmaceuticals, and (3) other areas such as medicine, industrial processes and glycan synthesis where MALDI is extensively used. Much of the material relating to applications is presented in tabular form. The reported work shows increasing use of incorporation of new techniques such as ion mobility and the enormous impact that MALDI imaging is having. MALDI, although invented nearly 40 years ago is still an ideal technique for carbohydrate analysis and advancements in the technique and range of applications show little sign of diminishing.
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Affiliation(s)
- David J Harvey
- Nuffield Department of Medicine, Target Discovery Institute, University of Oxford, Oxford, UK
- Department of Chemistry, University of Oxford, Oxford, Oxfordshire, United Kingdom
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Martínez-Trejo A, Ruiz-Ruiz JM, Gonzalez-Avila LU, Saldaña-Padilla A, Hernández-Cortez C, Loyola-Cruz MA, Bello-López JM, Castro-Escarpulli G. Evasion of Antimicrobial Activity in Acinetobacter baumannii by Target Site Modifications: An Effective Resistance Mechanism. Int J Mol Sci 2022; 23:6582. [PMID: 35743027 DOI: 10.3390/ijms23126582] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2022] [Revised: 06/05/2022] [Accepted: 06/10/2022] [Indexed: 11/17/2022] Open
Abstract
Acinetobacter baumannii is a Gram-negative bacillus that causes multiple infections that can become severe, mainly in hospitalized patients. Its high ability to persist on abiotic surfaces and to resist stressors, together with its high genomic plasticity, make it a remarkable pathogen. Currently, the isolation of strains with high antimicrobial resistance profiles has gained relevance, which complicates patient treatment and prognosis. This resistance capacity is generated by various mechanisms, including the modification of the target site where antimicrobial action is directed. This mechanism is mainly generated by genetic mutations and contributes to resistance against a wide variety of antimicrobials, such as β-lactams, macrolides, fluoroquinolones, aminoglycosides, among others, including polymyxin resistance, which includes colistin, a rescue antimicrobial used in the treatment of multidrug-resistant strains of A. baumannii and other Gram-negative bacteria. Therefore, the aim of this review is to provide a detailed and up-to-date description of antimicrobial resistance mediated by the target site modification in A. baumannii, as well as to detail the therapeutic options available to fight infections caused by this bacterium.
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Herrera CM, Voss BJ, Trent MS. Homeoviscous Adaptation of the Acinetobacter baumannii Outer Membrane: Alteration of Lipooligosaccharide Structure during Cold Stress. mBio 2021; 12:e0129521. [PMID: 34425709 DOI: 10.1128/mBio.01295-21] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [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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Liao W, Lin J, Jia H, Zhou C, Zhang Y, Lin Y, Ye J, Cao J, Zhou T. Resistance and Heteroresistance to Colistin in Escherichia coli Isolates from Wenzhou, China. Infect Drug Resist 2020; 13:3551-3561. [PMID: 33116674 PMCID: PMC7553605 DOI: 10.2147/idr.s273784] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Accepted: 09/15/2020] [Indexed: 12/20/2022] Open
Abstract
Background Colistin is being administered as last-line therapy for patients that have failed to respond to other available antibiotics that are active against Escherichia coli. The underlying mechanisms of colistin resistance and heteroresistance remain largely uncharacterized. The present study investigated the mechanisms of resistance and heteroresistance to colistin in Escherichia coli isolates from Wenzhou, China. Materials and Methods Colistin resistance was detected by the broth microdilution method (BMD). Colistin heteroresistance was determined by population analysis profiles (PAPs). The polymerase chain reaction (PCR) was conducted to detect mcr-1, mcr-2, mcr-3, pmrA, pmrB, phoP, phoQ and mgrB, and quantitative real-time PCR (qRT-PCR) was used to determine the expression levels of mcr-1, pmrC, pmrA and pmrB. Lipid A characterization was conducted by matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS). Results 0.69% (2/291) of Escherichia coli strains were resistant to colistin, whereas the heteroresistance rate reached 1.37% (4/291). mcr-1, the mobile colistin-resistance gene, was present in the two resistant isolates. The substitutions in PmrB were detected in the two heteroresistant isolates. The transcripts levels of the pmrCAB operon were upregulated in two of the heteroresistant isolates. carbonylcyanide m-chlorophenylhydrazone (CCCP) was able to reverse colistin resistance of all isolates tested and exhibited a significantly higher effect on colistin-heteroresistant isolates. MALDI-TOF MS indicated that the additional phosphoethanolamine (PEtn) moieties in lipid A profiles were present both in colistin-resistant and heteroresistant isolates. Conclusion The present study was the first to investigate the differential mechanisms between colistin resistance and heteroresistance. The development of colistin heteroresistance should be addressed in future clinical surveillance.
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Affiliation(s)
- Wenli Liao
- Department of Clinical Laboratory, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang Province, People's Republic of China
| | - Jie Lin
- Assisted Reproduction Unit, Department of Obstetrics and Gynecology, Sir Run Run Shaw Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang, People's Republic of China
| | - Huaiyu Jia
- Department of Clinical Laboratory, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang Province, People's Republic of China
| | - Cui Zhou
- Department of Clinical Laboratory, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang Province, People's Republic of China
| | - Ying Zhang
- Department of Medical Laboratory Science, School of Laboratory Medicine and Life Science, Wenzhou Medical University, Wenzhou, Zhejiang Province, People's Republic of China
| | - Yishuai Lin
- Department of Medical Laboratory Science, School of Laboratory Medicine and Life Science, Wenzhou Medical University, Wenzhou, Zhejiang Province, People's Republic of China
| | - Jianzhong Ye
- Department of Clinical Laboratory, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang Province, People's Republic of China
| | - Jianming Cao
- Department of Medical Laboratory Science, School of Laboratory Medicine and Life Science, Wenzhou Medical University, Wenzhou, Zhejiang Province, People's Republic of China
| | - Tieli Zhou
- Department of Clinical Laboratory, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang Province, People's Republic of China
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Powers MJ, Simpson BW, Trent MS. The Mla pathway in Acinetobacter baumannii has no demonstrable role in anterograde lipid transport. eLife 2020; 9:56571. [PMID: 32880370 PMCID: PMC7500953 DOI: 10.7554/elife.56571] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2020] [Accepted: 09/02/2020] [Indexed: 12/17/2022] Open
Abstract
The asymmetric outer membrane (OM) of Gram-negative bacteria functions as a selective permeability barrier to the environment. Perturbations to OM lipid asymmetry sensitize the cell to antibiotics. As such, mechanisms involved in lipid asymmetry are fundamental to our understanding of OM lipid homeostasis. One such mechanism, the Maintenance of lipid asymmetry (Mla) pathway has been proposed to extract mislocalized glycerophospholipids from the outer leaflet of the OM and return them to the inner membrane (IM). Work on this pathway in Acinetobacter baumannii support conflicting models for the directionality of the Mla system being retrograde (OM to IM) or anterograde (IM to OM). Here, we show conclusively that A. baumannii mla mutants exhibit no defects in anterograde transport. Furthermore, we identify an allele of the GTPase obgE that is synthetically sick in the absence of Mla; providing another link between cell envelope homeostasis and stringent response.
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Affiliation(s)
- Matthew J Powers
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, United States.,Department of Microbiology, College of Arts and Sciences, University of Georgia, Athens, United States
| | - Brent W Simpson
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, United States
| | - M Stephen Trent
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, United States.,Department of Microbiology, College of Arts and Sciences, University of Georgia, Athens, United States
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Vázquez-López R, Solano-Gálvez SG, Juárez Vignon-Whaley JJ, Abello Vaamonde JA, Padró Alonzo LA, Rivera Reséndiz A, Muleiro Álvarez M, Vega López EN, Franyuti-Kelly G, Álvarez-Hernández DA, Moncaleano Guzmán V, Juárez Bañuelos JE, Marcos Felix J, González Barrios JA, Barrientos Fortes T. Acinetobacter baumannii Resistance: A Real Challenge for Clinicians. Antibiotics (Basel) 2020; 9:antibiotics9040205. [PMID: 32340386 PMCID: PMC7235888 DOI: 10.3390/antibiotics9040205] [Citation(s) in RCA: 111] [Impact Index Per Article: 27.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2019] [Revised: 01/29/2020] [Accepted: 02/05/2020] [Indexed: 12/21/2022] Open
Abstract
Acinetobacter baumannii (named in honor of the American bacteriologists Paul and Linda Baumann) is a Gram-negative, multidrug-resistant (MDR) pathogen that causes nosocomial infections, especially in intensive care units (ICUs) and immunocompromised patients with central venous catheters. A. baumannii has developed a broad spectrum of antimicrobial resistance, associated with a higher mortality rate among infected patients compared with other non-baumannii species. In terms of clinical impact, resistant strains are associated with increases in both in-hospital length of stay and mortality. A. baumannii can cause a variety of infections; most involve the respiratory tract, especially ventilator-associated pneumonia, but bacteremia and skin wound infections have also been reported, the latter of which has been prominently observed in the context of war-related trauma. Cases of meningitis associated with A. baumannii have been documented. The most common risk factor for the acquisition of MDR A baumannii is previous antibiotic use, following by mechanical ventilation, length of ICU/hospital stay, severity of illness, and use of medical devices. Current efforts focus on addressing all the antimicrobial resistance mechanisms described in A. baumannii, with the objective of identifying the most promising therapeutic scheme. Bacteriophage- and artilysin-based therapeutic approaches have been described as effective, but further research into their clinical use is required.
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Affiliation(s)
- Rosalino Vázquez-López
- Departamento de Microbiología del Centro de Investigación en Ciencias de la Salud (CICSA), FCS, Universidad Anáhuac México Norte, Huixquilucan 52786, Mexico; (J.J.J.V.-W.); (J.A.A.V.); (L.A.P.A.); (A.R.R.); (M.M.Á.); (D.A.Á.-H.); (V.M.G.); (J.E.J.B.)
- Correspondence: or ; Tel.: +52-56-270210 (ext. 7302)
| | - Sandra Georgina Solano-Gálvez
- Departamento de Microbiología y Parasitología, Facultad de Medicina, Universidad Nacional Autónoma de México, Ciudad de Mexico 04510, Mexico;
| | - Juan José Juárez Vignon-Whaley
- Departamento de Microbiología del Centro de Investigación en Ciencias de la Salud (CICSA), FCS, Universidad Anáhuac México Norte, Huixquilucan 52786, Mexico; (J.J.J.V.-W.); (J.A.A.V.); (L.A.P.A.); (A.R.R.); (M.M.Á.); (D.A.Á.-H.); (V.M.G.); (J.E.J.B.)
| | - Jorge Andrés Abello Vaamonde
- Departamento de Microbiología del Centro de Investigación en Ciencias de la Salud (CICSA), FCS, Universidad Anáhuac México Norte, Huixquilucan 52786, Mexico; (J.J.J.V.-W.); (J.A.A.V.); (L.A.P.A.); (A.R.R.); (M.M.Á.); (D.A.Á.-H.); (V.M.G.); (J.E.J.B.)
| | - Luis Andrés Padró Alonzo
- Departamento de Microbiología del Centro de Investigación en Ciencias de la Salud (CICSA), FCS, Universidad Anáhuac México Norte, Huixquilucan 52786, Mexico; (J.J.J.V.-W.); (J.A.A.V.); (L.A.P.A.); (A.R.R.); (M.M.Á.); (D.A.Á.-H.); (V.M.G.); (J.E.J.B.)
| | - Andrés Rivera Reséndiz
- Departamento de Microbiología del Centro de Investigación en Ciencias de la Salud (CICSA), FCS, Universidad Anáhuac México Norte, Huixquilucan 52786, Mexico; (J.J.J.V.-W.); (J.A.A.V.); (L.A.P.A.); (A.R.R.); (M.M.Á.); (D.A.Á.-H.); (V.M.G.); (J.E.J.B.)
| | - Mauricio Muleiro Álvarez
- Departamento de Microbiología del Centro de Investigación en Ciencias de la Salud (CICSA), FCS, Universidad Anáhuac México Norte, Huixquilucan 52786, Mexico; (J.J.J.V.-W.); (J.A.A.V.); (L.A.P.A.); (A.R.R.); (M.M.Á.); (D.A.Á.-H.); (V.M.G.); (J.E.J.B.)
| | - Eunice Nabil Vega López
- Medical IMPACT, Infectious Diseases Department, Mexico City 53900, Mexico; (E.N.V.L.); (G.F.-K.)
| | - Giorgio Franyuti-Kelly
- Medical IMPACT, Infectious Diseases Department, Mexico City 53900, Mexico; (E.N.V.L.); (G.F.-K.)
| | - Diego Abelardo Álvarez-Hernández
- Departamento de Microbiología del Centro de Investigación en Ciencias de la Salud (CICSA), FCS, Universidad Anáhuac México Norte, Huixquilucan 52786, Mexico; (J.J.J.V.-W.); (J.A.A.V.); (L.A.P.A.); (A.R.R.); (M.M.Á.); (D.A.Á.-H.); (V.M.G.); (J.E.J.B.)
| | - Valentina Moncaleano Guzmán
- Departamento de Microbiología del Centro de Investigación en Ciencias de la Salud (CICSA), FCS, Universidad Anáhuac México Norte, Huixquilucan 52786, Mexico; (J.J.J.V.-W.); (J.A.A.V.); (L.A.P.A.); (A.R.R.); (M.M.Á.); (D.A.Á.-H.); (V.M.G.); (J.E.J.B.)
| | - Jorge Ernesto Juárez Bañuelos
- Departamento de Microbiología del Centro de Investigación en Ciencias de la Salud (CICSA), FCS, Universidad Anáhuac México Norte, Huixquilucan 52786, Mexico; (J.J.J.V.-W.); (J.A.A.V.); (L.A.P.A.); (A.R.R.); (M.M.Á.); (D.A.Á.-H.); (V.M.G.); (J.E.J.B.)
| | - José Marcos Felix
- Coordinación Ciclos Clínicos Medicina, FCS, Universidad Anáhuac México Norte, Huixquilucan 52786, Mexico;
| | - Juan Antonio González Barrios
- Laboratorio de Medicina Genómica, Hospital Regional “1º de Octubre”, ISSSTE, Av. Instituto Politécnico Nacional 1669, Lindavista, Gustavo A. Madero, Ciudad de Mexico 07300, Mexico;
| | - Tomás Barrientos Fortes
- Dirección Sistema Universitario de Salud de la Universidad Anáhuac México (SUSA), Huixquilucan 52786, Mexico;
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Lin J, Xu C, Fang R, Cao J, Zhang X, Zhao Y, Dong G, Sun Y, Zhou T. Resistance and Heteroresistance to Colistin in Pseudomonas aeruginosa Isolates from Wenzhou, China. Antimicrob Agents Chemother 2019; 63:e00556-19. [PMID: 31383654 DOI: 10.1128/AAC.00556-19] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2019] [Accepted: 06/28/2019] [Indexed: 01/26/2023] Open
Abstract
The goal was to investigate the mechanisms of colistin resistance and heteroresistance in Pseudomonas aeruginosa clinical isolates. Colistin resistance was determined by the broth microdilution method. Colistin heteroresistance was evaluated by population analysis profiling. Time-kill assays were also conducted. PCR sequencing was performed to detect the resistance genes among (hetero)resistant isolates, and quantitative real-time PCR assays were performed to determine their expression levels. Pulsed-field gel electrophoresis and multilocus sequence typing were performed. Lipid A characteristics were determined via matrix-assisted laser desorption-ionization time of flight mass spectrometry (MALDI-TOF MS). Two resistant isolates and 9 heteroresistant isolates were selected in this study. Substitutions in PmrB were detected in 2 resistant isolates. Among heteroresistant isolates, 8 of 9 heteroresistant isolates had nonsynonymous PmrB substitutions, and 2 isolates, including 1 with a PmrB substitution, had PhoQ alterations. Correspondingly, the expression levels of pmrA or phoP were upregulated in PmrB- or PhoQ-substituted isolates. One isolate also found alterations in ParRS and CprRS. The transcript levels of the pmrH gene were observed to increase across all investigated isolates. MALDI-TOF MS showed additional 4-amino-4-deoxy-l-arabinose (l-Ara4N) moieties in lipid A profiles in (hetero)resistant isolates. In conclusion, both colistin resistance and heteroresistance in P. aeruginosa in this study mainly involved alterations of the PmrAB regulatory system. There were strong associations between mutations in specific genetic loci for lipid A synthesis and regulation of modifications to lipid A. The transition of colistin heteroresistance to resistance should be addressed in future clinical surveillance.
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