1
|
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] [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.
Collapse
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.
| |
Collapse
|
2
|
Simpson BW, Gilmore MC, McLean AB, Cava F, Trent MS. Escherichia coli CadB is capable of promiscuously transporting muropeptides and contributing to peptidoglycan recycling. J Bacteriol 2024; 206:e0036923. [PMID: 38169298 PMCID: PMC10810205 DOI: 10.1128/jb.00369-23] [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: 10/31/2023] [Accepted: 12/05/2023] [Indexed: 01/05/2024] Open
Abstract
The bacterial peptidoglycan (PG) cell wall is remodeled during growth and division, releasing fragments called muropeptides. Muropeptides can be internalized and reused in a process called PG recycling. Escherichia coli is highly devoted to recycling muropeptides and is known to have at least two transporters, AmpG and OppBCDF, that import them into the cytoplasm. While studying mutants lacking AmpG, we unintentionally isolated mutations that led to the altered expression of a third transporter, CadB. CadB is normally upregulated under acidic pH conditions and is an antiporter for lysine and cadaverine. Here, we explored if CadB was altering PG recycling to assist in the absence of AmpG. Surprisingly, CadB overexpression was able to restore PG recycling when both AmpG and OppBCDF were absent. CadB was found to import freed PG peptides, a subpopulation of muropeptides, through a promiscuous activity. Altogether, our data support that CadB is a third transporter capable of contributing to PG recycling. IMPORTANCE Bacteria produce a rigid mesh cell wall. During growth, the cell wall is remodeled, which releases cell wall fragments. If released into the extracellular environment, cell wall fragments can trigger inflammation by the immune system of a host. Gastrointestinal bacteria, like Escherichia coli, have dedicated pathways to recycle almost all cell wall fragments they produce. E. coli contains two known recycling transporters, AmpG and Opp, that we previously showed are optimized for growth in different environments. Here, we identify that a third transporter, CadB, can also contribute to cell wall recycling. This work expands our understanding of cell wall recycling and highlights the dedication of organisms like E. coli to ensure high recycling in multiple growth environments.
Collapse
Affiliation(s)
- Brent W. Simpson
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, Georgia, USA
| | - Michael C. Gilmore
- Laboratory for Molecular Infection Medicine Sweden, Department of Molecular Biology, Umeå Centre for Microbial Research, SciLifeLab, Umeå University, Umeå, Sweden
| | - Amanda Briann McLean
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, Georgia, USA
| | - Felipe Cava
- Laboratory for Molecular Infection Medicine Sweden, Department of Molecular Biology, Umeå Centre for Microbial Research, SciLifeLab, Umeå University, Umeå, Sweden
| | - M. Stephen Trent
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, Georgia, USA
- Department of Microbiology, College of Arts and Sciences, University of Georgia, Athens, Georgia, USA
| |
Collapse
|
3
|
Hurst MN, Beebout CJ, Hollingsworth A, Guckes KR, Purcell A, Bermudez TA, Williams D, Reasoner SA, Trent MS, Hadjifrangiskou M. The QseB response regulator imparts tolerance to positively charged antibiotics by controlling metabolism and minor changes to LPS. mSphere 2023; 8:e0005923. [PMID: 37676915 PMCID: PMC10597456 DOI: 10.1128/msphere.00059-23] [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: 02/01/2023] [Accepted: 06/02/2023] [Indexed: 09/09/2023] Open
Abstract
The modification of lipopolysaccharide (LPS) in Escherichia coli and Salmonella spp. is primarily controlled by the two-component system PmrAB. LPS modification allows bacteria to avoid killing by positively charged antibiotics like polymyxin B (PMB). We previously demonstrated that in uropathogenic E. coli (UPEC), the sensor histidine kinase PmrB also activates a non-cognate transcription factor, QseB, and this activation somehow augments PMB tolerance in UPEC. Here, we demonstrate-for the first time-that in the absence of the canonical LPS transcriptional regulator, PmrA, QseB can direct some modifications on the LPS. In agreement with this observation, transcriptional profiling analyses demonstrate regulatory overlaps between PmrA and QseB in terms of regulating LPS modification genes. However, both PmrA and QseB must be present for UPEC to mount robust tolerance to PMB. Transcriptional and metabolomic analyses also reveal that QseB transcriptionally regulates the metabolism of glutamate and 2-oxoglutarate, which are consumed and produced during the modification of lipid A. We show that deletion of qseB alters glutamate levels in the bacterial cells. The qseB deletion mutant, which is susceptible to positively charged antibiotics, is rescued by exogenous addition of 2-oxoglutarate. These findings uncover a previously unknown mechanism of metabolic control of antibiotic tolerance that may be contributing to antibiotic treatment failure in the clinic. IMPORTANCE Although antibiotic prescriptions are guided by well-established susceptibility testing methods, antibiotic treatments oftentimes fail. The presented work is significant because it uncovers a mechanism by which bacteria transiently avoid killing by antibiotics. This mechanism involves two closely related transcription factors, PmrA and QseB, which are conserved across Enterobacterales. We demonstrate that PmrA and QseB share regulatory targets in lipid A modification pathway and prove that QseB can orchestrate modifications of lipid A in Escherichia coli in the absence of PmrA. Finally, we show that QseB controls glutamate metabolism during the antibiotic response. These results suggest that rewiring of QseB-mediated metabolic genes could lead to stable antibiotic resistance in subpopulations within the host, thereby contributing to antibiotic treatment failure.
Collapse
Affiliation(s)
- Melanie N. Hurst
- Division of Molecular Pathogenesis, Department of Pathology, Microbiology & Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Connor J. Beebout
- Division of Molecular Pathogenesis, Department of Pathology, Microbiology & Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Alexis Hollingsworth
- Department of Biological Sciences, Vanderbilt University, Nashville, Tennessee, USA
| | - Kirsten R. Guckes
- Division of Molecular Pathogenesis, Department of Pathology, Microbiology & Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Alexandria Purcell
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, Georgia, USA
| | - Tomas A. Bermudez
- Division of Molecular Pathogenesis, Department of Pathology, Microbiology & Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Diamond Williams
- Department of Biological Sciences, Vanderbilt University, Nashville, Tennessee, USA
| | - Seth A. Reasoner
- Division of Molecular Pathogenesis, Department of Pathology, Microbiology & Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - M. Stephen Trent
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, Georgia, USA
| | - Maria Hadjifrangiskou
- Division of Molecular Pathogenesis, Department of Pathology, Microbiology & Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, USA
- Vanderbilt Institute for Infection, Immunology and Inflammation, Nashville, Tennessee, USA
- Center for Personalized Microbiology, Department of Pathology, Microbiology & Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| |
Collapse
|
4
|
Rogga V, Kosalec I. Untying the anchor for the lipopolysaccharide: lipid A structural modification systems offer diagnostic and therapeutic options to tackle polymyxin resistance. Arh Hig Rada Toksikol 2023; 74:145-166. [PMID: 37791675 PMCID: PMC10549895 DOI: 10.2478/aiht-2023-74-3717] [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: 01/01/2023] [Revised: 01/01/2023] [Accepted: 07/01/2023] [Indexed: 10/05/2023] Open
Abstract
Polymyxin antibiotics are the last resort for treating patients in intensive care units infected with multiple-resistant Gram-negative bacteria. Due to their polycationic structure, their mode of action is based on an ionic interaction with the negatively charged lipid A portion of the lipopolysaccharide (LPS). The most prevalent polymyxin resistance mechanisms involve covalent modifications of lipid A: addition of the cationic sugar 4-amino-L-arabinose (L-Ara4N) and/or phosphoethanolamine (pEtN). The modified structure of lipid A has a lower net negative charge, leading to the repulsion of polymyxins and bacterial resistance to membrane disruption. Genes encoding the enzymatic systems involved in these modifications can be transferred either through chromosomes or mobile genetic elements. Therefore, new approaches to resistance diagnostics have been developed. On another note, interfering with these enzymatic systems might offer new therapeutic targets for drug discovery. This literature review focuses on diagnostic approaches based on structural changes in lipid A and on the therapeutic potential of molecules interfering with these changes.
Collapse
Affiliation(s)
- Vanessa Rogga
- University of Zagreb Faculty of Pharmacy and Biochemistry, Department of Microbiology, Zagreb, Croatia
| | - Ivan Kosalec
- University of Zagreb Faculty of Pharmacy and Biochemistry, Department of Microbiology, Zagreb, Croatia
| |
Collapse
|
5
|
Chen Q, Zhang W, Xiao L, Sun Q, Wu F, Liu G, Wang Y, Pan Y, Wang Q, Zhang J. Multi-Omics Reveals the Effect of Crossbreeding on Some Precursors of Flavor and Nutritional Quality of Pork. Foods 2023; 12:3237. [PMID: 37685169 PMCID: PMC10486348 DOI: 10.3390/foods12173237] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2023] [Revised: 08/25/2023] [Accepted: 08/25/2023] [Indexed: 09/10/2023] Open
Abstract
Over the last several decades, China has continuously introduced Duroc boars and used them as breeding boars. Although this crossbreeding method has increased pork production, it has affected pork quality. Nowadays, one of the primary goals of industrial breeding and production systems is to enhance the quality of meat. This research analyzed the molecular mechanisms that control the quality of pork and may be used as a guide for future efforts to enhance meat quality. The genetic mechanisms of cross-breeding for meat quality improvement were investigated by combining transcriptome and metabolome analysis, using Chinese native Jiaxing black (JXB) pigs and crossbred Duroc × Duroc × Berkshire × JXB (DDBJ) pigs. In the longissimus Dorsi muscle, the content of inosine monophosphate, polyunsaturated fatty acid, and amino acids were considerably higher in JXB pigs in contrast with that of DDBJ pigs, whereas DDBJ pigs have remarkably greater levels of polyunsaturated fatty acids than JXB pigs. Differentially expressed genes (DEGs) and differential metabolites were identified using transcriptomic and metabolomic KEGG enrichment analyses. Differential metabolites mainly include amino acids, fatty acids, and phospholipids. In addition, several DEGs that may explain differences in meat quality between the two pig types were found, including genes associated with the metabolism of lipids (e.g., DGKA, LIPG, and LPINI), fatty acid (e.g., ELOVL5, ELOVL4, and ACAT2), and amino acid (e.g., SLC7A2, SLC7A4). Combined with the DEGS-enriched signaling pathways, the regulatory mechanisms related to amino acids, fatty acids, and phospholipids were mapped. The abundant metabolic pathways and DEGs may provide insight into the specific molecular mechanism that regulates meat quality. Optimizing the composition of fatty acids, phospholipids, amino acids, and other compounds in pork is conducive to improving meat quality. Overall, these findings will provide useful information and further groundwork for enhancing the meat quality that may be achieved via hybrid breeding.
Collapse
Affiliation(s)
- Qiangqiang Chen
- College of Animal Science, Zhejiang University, Hangzhou 310058, China; (Q.C.); (W.Z.); (L.X.); (Q.S.); (F.W.); (Y.P.); (Q.W.)
| | - Wei Zhang
- College of Animal Science, Zhejiang University, Hangzhou 310058, China; (Q.C.); (W.Z.); (L.X.); (Q.S.); (F.W.); (Y.P.); (Q.W.)
| | - Lixia Xiao
- College of Animal Science, Zhejiang University, Hangzhou 310058, China; (Q.C.); (W.Z.); (L.X.); (Q.S.); (F.W.); (Y.P.); (Q.W.)
| | - Qian Sun
- College of Animal Science, Zhejiang University, Hangzhou 310058, China; (Q.C.); (W.Z.); (L.X.); (Q.S.); (F.W.); (Y.P.); (Q.W.)
| | - Fen Wu
- College of Animal Science, Zhejiang University, Hangzhou 310058, China; (Q.C.); (W.Z.); (L.X.); (Q.S.); (F.W.); (Y.P.); (Q.W.)
| | - Guoliang Liu
- Zhejiang Qinglian Food Co., Ltd., Jiaxing 314317, China;
| | - Yuan Wang
- College of Animal Science and Technology, China Agricultural University, Beijing 100107, China;
| | - Yuchun Pan
- College of Animal Science, Zhejiang University, Hangzhou 310058, China; (Q.C.); (W.Z.); (L.X.); (Q.S.); (F.W.); (Y.P.); (Q.W.)
| | - Qishan Wang
- College of Animal Science, Zhejiang University, Hangzhou 310058, China; (Q.C.); (W.Z.); (L.X.); (Q.S.); (F.W.); (Y.P.); (Q.W.)
| | - Jinzhi Zhang
- College of Animal Science, Zhejiang University, Hangzhou 310058, China; (Q.C.); (W.Z.); (L.X.); (Q.S.); (F.W.); (Y.P.); (Q.W.)
| |
Collapse
|
6
|
Gaballa A, Wiedmann M, Carroll LM. More than mcr: canonical plasmid- and transposon-encoded mobilized colistin resistance genes represent a subset of phosphoethanolamine transferases. Front Cell Infect Microbiol 2023; 13:1060519. [PMID: 37360531 PMCID: PMC10285318 DOI: 10.3389/fcimb.2023.1060519] [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: 10/03/2022] [Accepted: 05/19/2023] [Indexed: 06/28/2023] Open
Abstract
Mobilized colistin resistance genes (mcr) may confer resistance to the last-resort antimicrobial colistin and can often be transmitted horizontally. mcr encode phosphoethanolamine transferases (PET), which are closely related to chromosomally encoded, intrinsic lipid modification PET (i-PET; e.g., EptA, EptB, CptA). To gain insight into the evolution of mcr within the context of i-PET, we identified 69,814 MCR-like proteins present across 256 bacterial genera (obtained by querying known MCR family representatives against the National Center for Biotechnology Information [NCBI] non-redundant protein database via protein BLAST). We subsequently identified 125 putative novel mcr-like genes, which were located on the same contig as (i) ≥1 plasmid replicon and (ii) ≥1 additional antimicrobial resistance gene (obtained by querying the PlasmidFinder database and NCBI's National Database of Antibiotic Resistant Organisms, respectively, via nucleotide BLAST). At 80% amino acid identity, these putative novel MCR-like proteins formed 13 clusters, five of which represented putative novel MCR families. Sequence similarity and a maximum likelihood phylogeny of mcr, putative novel mcr-like, and ipet genes indicated that sequence similarity was insufficient to discriminate mcr from ipet genes. A mixed-effect model of evolution (MEME) indicated that site- and branch-specific positive selection played a role in the evolution of alleles within the mcr-2 and mcr-9 families. MEME suggested that positive selection played a role in the diversification of several residues in structurally important regions, including (i) a bridging region that connects the membrane-bound and catalytic periplasmic domains, and (ii) a periplasmic loop juxtaposing the substrate entry tunnel. Moreover, eptA and mcr were localized within different genomic contexts. Canonical eptA genes were typically chromosomally encoded in an operon with a two-component regulatory system or adjacent to a TetR-type regulator. Conversely, mcr were represented by single-gene operons or adjacent to pap2 and dgkA, which encode a PAP2 family lipid A phosphatase and diacylglycerol kinase, respectively. Our data suggest that eptA can give rise to "colistin resistance genes" through various mechanisms, including mobilization, selection, and diversification of genomic context and regulatory pathways. These mechanisms likely altered gene expression levels and enzyme activity, allowing bona fide eptA to evolve to function in colistin resistance.
Collapse
Affiliation(s)
- Ahmed Gaballa
- Department of Food Science, Cornell University, Ithaca, NY, United States
| | - Martin Wiedmann
- Department of Food Science, Cornell University, Ithaca, NY, United States
| | - Laura M. Carroll
- Department of Clinical Microbiology, SciLifeLab, Umeå University, Umeå, Sweden
- Laboratory for Molecular Infection Medicine Sweden (MIMS), Umeå University, Umeå, Sweden
- Umeå Centre for Microbial Research, Umeå University, Umeå, Sweden
- Integrated Science Lab, Umeå University, Umeå, Sweden
| |
Collapse
|
7
|
Purcell AB, Simpson BW, Trent MS. Impact of the cAMP-cAMP Receptor Protein Regulatory Complex on Lipopolysaccharide Modifications and Polymyxin B Resistance in Escherichia coli. J Bacteriol 2023; 205:e0006723. [PMID: 37070977 PMCID: PMC10210979 DOI: 10.1128/jb.00067-23] [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: 02/15/2023] [Accepted: 03/17/2023] [Indexed: 04/19/2023] Open
Abstract
Gram-negative bacteria have a unique cell surface that can be modified to maintain bacterial fitness in diverse environments. A well-defined example is the modification of the lipid A component of lipopolysaccharide (LPS), which promotes resistance to polymyxin antibiotics and antimicrobial peptides. In many organisms, such modifications include the addition of the amine-containing constituents 4-amino-4-deoxy-l-arabinose (l-Ara4N) and phosphoethanolamine (pEtN). Addition of pEtN is catalyzed by EptA, which uses phosphatidylethanolamine (PE) as its substrate donor, resulting in production of diacylglycerol (DAG). DAG is then quickly recycled into glycerophospholipid (GPL) synthesis by the DAG kinase A (DgkA) to produce phosphatidic acid, the major GPL precursor. Previously, we hypothesized that loss of DgkA recycling would be detrimental to the cell when LPS is heavily modified. Instead, we found that DAG accumulation inhibits EptA activity, preventing further degradation of PE, the predominant GPL of the cell. However, DAG inhibition of pEtN addition results in complete loss of polymyxin resistance. Here, we selected for suppressors to find a mechanism of resistance independent of DAG recycling or pEtN modification. Disrupting the gene encoding the adenylate cyclase, cyaA, fully restored antibiotic resistance without restoring DAG recycling or pEtN modification. Supporting this, disruptions of genes that reduce CyaA-derived cAMP formation (e.g., ptsI) or disruption of the cAMP receptor protein, Crp, also restored resistance. We found that loss of the cAMP-CRP regulatory complex was necessary for suppression and that resistance arises from a substantial increase in l-Ara4N-modified LPS, bypassing the need for pEtN modification. IMPORTANCE Gram-negative bacteria can alter the structure of their LPS to promote resistance to cationic antimicrobial peptides, including polymyxin antibiotics. Polymyxins are considered last-resort antibiotics for treatment against multidrug-resistant Gram-negative organisms. Here, we explore how changes in general metabolism and carbon catabolite repression pathways can alter LPS structure and influence polymyxin resistance.
Collapse
Affiliation(s)
- Alexandria B. Purcell
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, Georgia, USA
| | - Brent W. Simpson
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, Georgia, USA
| | - M. Stephen Trent
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, Georgia, USA
- Department of Microbiology, College of Arts and Sciences, University of Georgia, Athens, Georgia, USA
| |
Collapse
|
8
|
Carfrae LA, Rachwalski K, French S, Gordzevich R, Seidel L, Tsai CN, Tu MM, MacNair CR, Ovchinnikova OG, Clarke BR, Whitfield C, Brown ED. Inhibiting fatty acid synthesis overcomes colistin resistance. Nat Microbiol 2023:10.1038/s41564-023-01369-z. [PMID: 37127701 DOI: 10.1038/s41564-023-01369-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Accepted: 03/23/2023] [Indexed: 05/03/2023]
Abstract
Treating multidrug-resistant infections has increasingly relied on last-resort antibiotics, including polymyxins, for example colistin. As polymyxins are given routinely, the prevalence of their resistance is on the rise and increases mortality rates of sepsis patients. The global dissemination of plasmid-borne colistin resistance, driven by the emergence of mcr-1, threatens to diminish the therapeutic utility of polymyxins from an already shrinking antibiotic arsenal. Restoring sensitivity to polymyxins using combination therapy with sensitizing drugs is a promising approach to reviving its clinical utility. Here we describe the ability of the biotin biosynthesis inhibitor, MAC13772, to synergize with colistin exclusively against colistin-resistant bacteria. MAC13772 indirectly disrupts fatty acid synthesis (FAS) and restores sensitivity to the last-resort antibiotic, colistin. Accordingly, we found that combinations of colistin and other FAS inhibitors, cerulenin, triclosan and Debio1452-NH3, had broad potential against both chromosomal and plasmid-mediated colistin resistance in chequerboard and lysis assays. Furthermore, combination therapy with colistin and the clinically relevant FabI inhibitor, Debio1452-NH3, showed efficacy against mcr-1 positive Klebsiella pneumoniae and colistin-resistant Escherichia coli systemic infections in mice. Using chemical genomics, lipidomics and transcriptomics, we explored the mechanism of the interaction. We propose that inhibiting FAS restores colistin sensitivity by depleting lipid synthesis, leading to changes in phospholipid composition. In all, this work reveals a surprising link between FAS and colistin resistance.
Collapse
Affiliation(s)
- Lindsey A Carfrae
- Biochemistry and Biomedical Sciences, McMaster University, Hamilton, Ontario, Canada
- Institute of Infectious Disease Research, McMaster University, Hamilton, Ontario, Canada
| | - Kenneth Rachwalski
- Biochemistry and Biomedical Sciences, McMaster University, Hamilton, Ontario, Canada
- Institute of Infectious Disease Research, McMaster University, Hamilton, Ontario, Canada
| | - Shawn French
- Biochemistry and Biomedical Sciences, McMaster University, Hamilton, Ontario, Canada
- Institute of Infectious Disease Research, McMaster University, Hamilton, Ontario, Canada
| | - Rodion Gordzevich
- Biochemistry and Biomedical Sciences, McMaster University, Hamilton, Ontario, Canada
- Institute of Infectious Disease Research, McMaster University, Hamilton, Ontario, Canada
| | - Laura Seidel
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario, Canada
| | - Caressa N Tsai
- Biochemistry and Biomedical Sciences, McMaster University, Hamilton, Ontario, Canada
- Institute of Infectious Disease Research, McMaster University, Hamilton, Ontario, Canada
| | - Megan M Tu
- Biochemistry and Biomedical Sciences, McMaster University, Hamilton, Ontario, Canada
- Institute of Infectious Disease Research, McMaster University, Hamilton, Ontario, Canada
| | - Craig R MacNair
- Biochemistry and Biomedical Sciences, McMaster University, Hamilton, Ontario, Canada
- Institute of Infectious Disease Research, McMaster University, Hamilton, Ontario, Canada
| | - Olga G Ovchinnikova
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario, Canada
| | - Bradley R Clarke
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario, Canada
| | - Chris Whitfield
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario, Canada
| | - Eric D Brown
- Biochemistry and Biomedical Sciences, McMaster University, Hamilton, Ontario, Canada.
- Institute of Infectious Disease Research, McMaster University, Hamilton, Ontario, Canada.
| |
Collapse
|
9
|
Darby EM, Trampari E, Siasat P, Gaya MS, Alav I, Webber MA, Blair JMA. Molecular mechanisms of antibiotic resistance revisited. Nat Rev Microbiol 2023; 21:280-295. [PMID: 36411397 DOI: 10.1038/s41579-022-00820-y] [Citation(s) in RCA: 190] [Impact Index Per Article: 190.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/17/2022] [Indexed: 11/22/2022]
Abstract
Antibiotic resistance is a global health emergency, with resistance detected to all antibiotics currently in clinical use and only a few novel drugs in the pipeline. Understanding the molecular mechanisms that bacteria use to resist the action of antimicrobials is critical to recognize global patterns of resistance and to improve the use of current drugs, as well as for the design of new drugs less susceptible to resistance development and novel strategies to combat resistance. In this Review, we explore recent advances in understanding how resistance genes contribute to the biology of the host, new structural details of relevant molecular events underpinning resistance, the identification of new resistance gene families and the interactions between different resistance mechanisms. Finally, we discuss how we can use this information to develop the next generation of antimicrobial therapies.
Collapse
Affiliation(s)
- Elizabeth M Darby
- College of Medical and Dental Sciences, Institute of Microbiology and Infection, University of Birmingham, Birmingham, UK
| | | | - Pauline Siasat
- College of Medical and Dental Sciences, Institute of Microbiology and Infection, University of Birmingham, Birmingham, UK
| | | | - Ilyas Alav
- College of Medical and Dental Sciences, Institute of Microbiology and Infection, University of Birmingham, Birmingham, UK
| | - Mark A Webber
- Quadram Institute Bioscience, Norwich Research Park, Norwich, UK.
- Medical School, University of East Anglia, Norwich Research Park, Norwich, UK.
| | - Jessica M A Blair
- College of Medical and Dental Sciences, Institute of Microbiology and Infection, University of Birmingham, Birmingham, UK.
| |
Collapse
|
10
|
Hurst MN, Beebout CJ, Hollingsworth A, Guckes KR, Purcell A, Bermudez TA, Williams D, Reasoner SA, Trent MS, Hadjifrangiskou M. The QseB response regulator imparts tolerance to positively charged antibiotics by controlling metabolism and minor changes to LPS. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.01.10.523522. [PMID: 36711705 PMCID: PMC9882033 DOI: 10.1101/2023.01.10.523522] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
The modification of lipopolysaccharide (LPS) in Escherichia coli and Salmonella spp . is primarily controlled by the two-component system PmrAB. LPS modification allows bacteria to avoid killing by positively charged antibiotics like polymyxin B. We previously demonstrated that in uropathogenic E. coli (UPEC), the sensor histidine kinase PmrB also activates a non-cognate transcription factor, QseB, and this activation somehow augments polymyxin B tolerance in UPEC. Here, we demonstrate - for the first time - that in the absence of the canonical LPS transcriptional regulator, PmrA, QseB can direct some modifications on the LPS. In agreement with this observation, transcriptional profiling analyses demonstrate regulatory overlaps between PmrA and QseB in terms of regulating LPS modification genes. However, both PmrA and QseB must be present for UPEC to mount robust tolerance to polymyxin B. Transcriptional and metabolomic analyses also reveal that QseB transcriptionally regulates the metabolism of glutamate and 2-oxoglutarate, which are consumed and produced during the modification of lipid A. We show that deletion of qseB alters glutamate levels in the bacterial cells. The qseB deletion mutant, which is susceptible to positively charged antibiotics, is rescued by exogenous addition of 2-oxoglutarate. These findings uncover a previously unknown mechanism of metabolic control of antibiotic tolerance that may be contributing to antibiotic treatment failure in the clinic. IMPORTANCE Although antibiotic prescriptions are guided by well-established susceptibility testing methods, antibiotic treatments oftentimes fail. The presented work is significant, because it uncovers a mechanism by which bacteria transiently avoid killing by antibiotics. This mechanism involves two closely related transcription factors, PmrA and QseB, which are conserved across Enterobacteriaceae. We demonstrate that PmrA and QseB share regulatory targets in lipid A modification pathway and prove that QseB can orchestrate modifications of lipid A in E. coli in the absence of PmrA. Finally, we show that QseB controls glutamate metabolism during the antibiotic response. These results suggest that rewiring of QseB-mediated metabolic genes can lead to stable antibiotic resistance in subpopulations within the host, thereby contributing to antibiotic treatment failure.
Collapse
Affiliation(s)
- Melanie N. Hurst
- Division of Molecular Pathogenesis, Department of Pathology, Microbiology & Immunology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Connor J. Beebout
- Division of Molecular Pathogenesis, Department of Pathology, Microbiology & Immunology, Vanderbilt University Medical Center, Nashville, TN, USA
| | | | - Kirsten R. Guckes
- Division of Molecular Pathogenesis, Department of Pathology, Microbiology & Immunology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Alexandria Purcell
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, GA 30602
| | - Tomas A. Bermudez
- Division of Molecular Pathogenesis, Department of Pathology, Microbiology & Immunology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Diamond Williams
- Department of Biological Sciences, Vanderbilt University, Nashville, TN, USA
| | - Seth A. Reasoner
- Division of Molecular Pathogenesis, Department of Pathology, Microbiology & Immunology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - M. Stephen Trent
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, GA 30602
| | - Maria Hadjifrangiskou
- Division of Molecular Pathogenesis, Department of Pathology, Microbiology & Immunology, Vanderbilt University Medical Center, Nashville, TN, USA
- Vanderbilt Institute for Infection, Immunology & Inflammation, Nashville, TN, USA
- Center for Personalized Microbiology, Department of Pathology, Microbiology & Immunology, Vanderbilt University Medical Center, Nashville, TN, USA
| |
Collapse
|