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Woods RA, Guzman Vela S, Alonzo F. Gram-positive pathogens, inflammation, and the host lipid environment. Curr Opin Microbiol 2025; 83:102581. [PMID: 39922181 DOI: 10.1016/j.mib.2025.102581] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2024] [Revised: 01/16/2025] [Accepted: 01/23/2025] [Indexed: 02/10/2025]
Abstract
The host lipid environment is a barrier to bacterial infection that comprises antimicrobial fatty acids and impermeable lipids that keep infectious agents from penetrating tissues. Bacterial and host lipids also signal to the immune system to regulate inflammation. Notably, bacterial lipids activate Toll-like receptors to initiate cytokine production, immune cell recruitment, and oxidative burst to control infection. Bacterial pathogens must adapt to the lipid environment, including bactericidal host fatty acids and inflammatory lipids, in ways that promote persistence in diverse tissues. Here, we discuss current advances in the understanding of Staphylococcus aureus lipid interactions that contribute to inflammation and innate immunity and consider the complex roles of host inflammatory lipids in driving immune defenses and antibacterial activity. In addition, we endeavor to introduce similar processes in other Gram-positive pathogens. These recent studies highlight the growing body of knowledge on the effects of lipid metabolism on host immunity and pathogenesis.
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Affiliation(s)
- Reginald A Woods
- Department of Microbiology and Immunology, University of Illinois at Chicago - College of Medicine, 835 S. Wolcott Avenue, Chicago, IL 60612, USA; Department of Pharmaceutical Sciences, University of Illinois at Chicago - Retzky College of Pharmacy, 833 S. Wood Street, Chicago, IL 60612, USA
| | - Sarai Guzman Vela
- Department of Microbiology and Immunology, University of Illinois at Chicago - College of Medicine, 835 S. Wolcott Avenue, Chicago, IL 60612, USA
| | - Francis Alonzo
- Department of Microbiology and Immunology, University of Illinois at Chicago - College of Medicine, 835 S. Wolcott Avenue, Chicago, IL 60612, USA.
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2
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Priyadharshini T, Sankar S, Ponnuraj K. Functional characterization of Staphylococcus aureus lipase 2 (SAL2) as a collagen adhesin. Biophys Chem 2025; 317:107352. [PMID: 39571274 DOI: 10.1016/j.bpc.2024.107352] [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: 08/23/2024] [Revised: 11/02/2024] [Accepted: 11/11/2024] [Indexed: 12/10/2024]
Abstract
Extracellular lipases of many pathogens have been characterized as human virulence factors. Staphylococcus aureus produces a variety of enzymes that aid in the pathogenesis of the bacterium to invade and destroy host tissues, resulting in a wide range of clinical illnesses. The lipase is one such enzyme, and the lipases produced by S. aureus (SAL1, SAL2 and SAL3) have been associated with the virulence of the bacterium. In the present study, we cloned, expressed and purified the mature lipase domain of SAL2 (rSAL2296-690) and characterized its interaction with human collagen type IV using biolayer interferometry (BLI), molecular docking and simulation studies. Collagen binds to rSAL2296-690 with an affinity of 3.261 μM. The enzymatic activity of rSAL2296-690 was analyzed in the presence of collagen and orlistat, a potent lipase inhibitor. The activity of rSAL2296-690 in the presence of collagen or orlistat was nearly 90 fold lower than that of the native rSAL2296-690. The optimal pH and temperature for rSAL2296-690 activity were found at 7 and 25 °C respectively. rSAL2296-690 found to be stable at pH 7 and exhibits thermostability in the temperature range 15-25 °C. With CaCl2 and ZnCl2, an increase in activity of rSAL2296-690 was observed whereas NiSO4, CuSO4, MnCl2, CoCl2 and MgCl2 reduced the activity. No substrate specificity was found with rSAL2296-690, as it cleaves different substrate lengths (C2, C6, C12 and C16) and triglyceride triolein. Interaction of rSAL2296-690 with metal-incubated collagen revealed that the binding affinity of collagen in the presence of NiSO4, CuSO4 and CoCl2 significantly reduced. Enzymatic and collagen binding studies provided insights into the putative collagen binding site on SAL2296-690, which is near the active site region of the molecule. This study thus revealed that rSAL2296-690 as a bi-functional molecule, acts not only as a lipase but also as a collagen adhesin.
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Affiliation(s)
- T Priyadharshini
- Centre of Advanced Study in Crystallography and Biophysics, University of Madras, Guindy Campus, Chennai 600 025, India
| | - Sreejanani Sankar
- Centre of Advanced Study in Crystallography and Biophysics, University of Madras, Guindy Campus, Chennai 600 025, India
| | - Karthe Ponnuraj
- Centre of Advanced Study in Crystallography and Biophysics, University of Madras, Guindy Campus, Chennai 600 025, India.
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3
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Ke S, Kil H, Roggy C, Shields T, Quinn Z, Quinn AP, Small JM, Towne FD, Brooks AE, Brooks BD. Potential Therapeutic Targets for Combination Antibody Therapy Against Staphylococcus aureus Infections. Antibiotics (Basel) 2024; 13:1046. [PMID: 39596740 PMCID: PMC11591076 DOI: 10.3390/antibiotics13111046] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2024] [Revised: 10/31/2024] [Accepted: 11/03/2024] [Indexed: 11/29/2024] Open
Abstract
Despite the significant advances in antibiotic treatments and therapeutics, Staphylococcus aureus (S. aureus) remains a formidable pathogen, primarily due to its rapid acquisition of antibiotic resistance. Known for its array of virulence factors, including surface proteins that promote adhesion to host tissues, enzymes that break down host barriers, and toxins that contribute to immune evasion and tissue destruction, S. aureus poses a serious health threat. Both the Centers for Disease Control and Prevention (CDC) and the World Health Organization (WHO) classify S. aureus as an ESKAPE pathogen, recognizing it as a critical threat to global health. The increasing prevalence of drug-resistant S. aureus underscores the need for new therapeutic strategies. This review discusses a promising approach that combines monoclonal antibodies targeting multiple S. aureus epitopes, offering synergistic efficacy in treating infections. Such strategies aim to reduce the capacity of the pathogen to develop resistance, presenting a potent adjunct or alternative to conventional antibiotic treatments.
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Affiliation(s)
- Sharon Ke
- Department of Biomedical Sciences, College of Osteopathic Medicine, Rocky Vista University, Parker, CO 80134, USA
| | - Hyein Kil
- Department of Surgery, Virtua Health, Camden, NJ 08103, USA
| | - Conner Roggy
- Department of Orthopaedic Surgery, Community Memorial Healthcare, Ventura, CA 93003, USA
| | - Ty Shields
- Department of Biomedical Sciences, College of Osteopathic Medicine, Rocky Vista University, Parker, CO 80134, USA
| | - Zachary Quinn
- Department of Biomedical Sciences, College of Osteopathic Medicine, Rocky Vista University, Parker, CO 80134, USA
| | - Alyssa P. Quinn
- Department of Biomedical Sciences, College of Osteopathic Medicine, Rocky Vista University, Parker, CO 80134, USA
| | - James M. Small
- Department of Biomedical Sciences, College of Osteopathic Medicine, Rocky Vista University, Parker, CO 80134, USA
| | - Francina D. Towne
- Department of Biomedical Sciences, College of Osteopathic Medicine, Rocky Vista University, Parker, CO 80134, USA
| | - Amanda E. Brooks
- Department of Biomedical Sciences, College of Osteopathic Medicine, Rocky Vista University, Parker, CO 80134, USA
| | - Benjamin D. Brooks
- Department of Biomedical Sciences, College of Osteopathic Medicine, Rocky Vista University, Parker, CO 80134, USA
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4
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Lichota A, Gwozdzinski K, Kowalczyk E, Kowalczyk M, Sienkiewicz M. Contribution of staphylococcal virulence factors in the pathogenesis of thrombosis. Microbiol Res 2024; 283:127703. [PMID: 38537329 DOI: 10.1016/j.micres.2024.127703] [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: 08/23/2023] [Revised: 03/20/2024] [Accepted: 03/20/2024] [Indexed: 04/17/2024]
Abstract
Staphylococci are responsible for many infections in humans, starting with skin and soft tissue infections and finishing with invasive diseases such as endocarditis, sepsis and pneumonia, which lead to high mortality. Patients with sepsis often demonstrate activated clotting pathways, decreased levels of anticoagulants, decreased fibrinolysis, activated endothelial surfaces and activated platelets. This results in disseminated intravascular coagulation and formation of a microthrombus, which can lead to a multiorgan failure. This review describes various staphylococcal virulence factors that contribute to vascular thrombosis, including deep vein thrombosis in infected patients. The article presents mechanisms of action of different factors released by bacteria in various host defense lines, which in turn can lead to formation of blood clots in the vessels.
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Affiliation(s)
- Anna Lichota
- Department of Pharmaceutical Microbiology and Microbiological Diagnostics, Medical University of Lodz, Lodz, Poland.
| | | | - Edward Kowalczyk
- Department of Pharmacology and Toxicology, Medical University of Lodz, Lodz, Poland
| | | | - Monika Sienkiewicz
- Department of Pharmaceutical Microbiology and Microbiological Diagnostics, Medical University of Lodz, Lodz, Poland
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5
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Ahmad Z, Singh S, Lee TJ, Sharma A, Lydic TA, Giri S, Kumar A. Untargeted and temporal analysis of retinal lipidome in bacterial endophthalmitis. Prostaglandins Other Lipid Mediat 2024; 171:106806. [PMID: 38185280 PMCID: PMC10939753 DOI: 10.1016/j.prostaglandins.2023.106806] [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: 06/09/2023] [Revised: 11/22/2023] [Accepted: 12/26/2023] [Indexed: 01/09/2024]
Abstract
Bacterial endophthalmitis is a blinding infectious disease typically acquired during ocular surgery. We previously reported significant alterations in retinal metabolism during Staphylococcus (S) aureus endophthalmitis. However, the changes in retinal lipid composition during endophthalmitis are unknown. Here, using a mouse model of S. aureus endophthalmitis and an untargeted lipidomic approach, we comprehensively analyzed temporal alterations in total lipids and oxylipin in retina. Our data showed a time-dependent increase in the levels of lipid classes, sphingolipids, glycerolipids, sterols, and non-esterified fatty acids, whereas levels of phospholipids decreased. Among lipid subclasses, phosphatidylcholine decreased over time. The oxylipin analysis revealed increased prostaglandin-E2, hydroxyeicosatetraenoic acids, docosahexaenoic acid, eicosapentaenoic acid, and α-linolenic acid. In-vitro studies using mouse bone marrow-derived macrophages showed increased lipid droplets and lipid-peroxide formation in response to S. aureus infection. Collectively, these findings suggest that S. aureus-infection alters the retinal lipid profile, which may contribute to the pathogenesis of bacterial endophthalmitis.
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Affiliation(s)
- Zeeshan Ahmad
- Department of Ophthalmology, Visual and Anatomical Sciences/ Kresge Eye Institute, Wayne State University School of Medicine, Detroit, MI, USA
| | - Sukhvinder Singh
- Department of Ophthalmology, Visual and Anatomical Sciences/ Kresge Eye Institute, Wayne State University School of Medicine, Detroit, MI, USA
| | - Tae Jin Lee
- Augusta University, Augusta, GA, USA. 4 Department of Ophthalmology, Augusta University, Augusta, GA, USA
| | - Ashok Sharma
- Augusta University, Augusta, GA, USA. 4 Department of Ophthalmology, Augusta University, Augusta, GA, USA
| | - Todd A Lydic
- Department of Physiology, Michigan State University, East Lansing, MI, USA
| | - Shailendra Giri
- Department of Neurology, Henry Ford Health System, Detroit, MI, USA
| | - Ashok Kumar
- Department of Ophthalmology, Visual and Anatomical Sciences/ Kresge Eye Institute, Wayne State University School of Medicine, Detroit, MI, USA; Department of Biochemistry, Microbiology, and Immunology, Wayne State University School of Medicine, Detroit, MI, USA.
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6
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Hasan WANBW, Nezhad NG, Yaacob MA, Salleh AB, Rahman RNZRA, Leow TC. Shifting the pH profiles of Staphylococcus epidermidis lipase (SEL) and Staphylococcus hyicus lipase (SHL) through generating chimeric lipases by DNA shuffling strategy. World J Microbiol Biotechnol 2024; 40:106. [PMID: 38386107 DOI: 10.1007/s11274-024-03927-x] [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: 11/11/2023] [Accepted: 02/14/2024] [Indexed: 02/23/2024]
Abstract
Enzymes are often required to function in a particular reaction condition by the industrial procedure. In order to identify critical residues affecting the optimum pH of Staphylococcal lipases, chimeric lipases from homologous lipases were generated via a DNA shuffling strategy. Chimeric 1 included mutations of G166S, K212E, T243A, H271Y. Chimeric 2 consisted of substitutions of K212E, T243A, H271Y. Chimeric 3 contained substitutions of K212E, R359L. From the screening results, the pH profiles for chimeric 1 and 2 lipases were shifted from pH 7 to 6. While the pH of chimeric 3 was shifted to 8. It seems the mutation of K212E in chimeric 1 and 2 decreased the pH to 6 by changing the electrostatic potential surface. Furthermore, chimeric 3 showed 10 ˚C improvement in the optimum temperature due to the rigidification of the catalytic loop through the hydrophobic interaction network. Moreover, the substrate specificity of chimeric 1 and 2 was increased towards the longer carbon length chains due to the mutation of T243A adjacent to the lid region through increasing the flexibility of the lid. Current study illustrated that directed evolution successfully modified lipase properties including optimum pH, temperature and substrate specificity through mutations, especially near catalytic and lid regions.
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Affiliation(s)
- Wan Atiqah Najiah Binti Wan Hasan
- Enzyme and Microbial Research Center, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, Serdang, 43400 UPM, Selangor, Malaysia
| | - Nima Ghahremani Nezhad
- Enzyme and Microbial Research Center, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, Serdang, 43400 UPM, Selangor, Malaysia
- Department of Cell and Molecular Biology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, Serdang, 43400 UPM, Selangor, Malaysia
| | - Mohd Adilin Yaacob
- Enzyme and Microbial Research Center, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, Serdang, 43400 UPM, Selangor, Malaysia
| | - Abu Bakar Salleh
- Enzyme and Microbial Research Center, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, Serdang, 43400 UPM, Selangor, Malaysia
| | - Raja Noor Zaliha Raja Abdul Rahman
- Enzyme and Microbial Research Center, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, Serdang, 43400 UPM, Selangor, Malaysia
- Department of Microbiology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, Serdang, 43400 UPM, Selangor, Malaysia
| | - Thean Chor Leow
- Enzyme and Microbial Research Center, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, Serdang, 43400 UPM, Selangor, Malaysia.
- Department of Cell and Molecular Biology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, Serdang, 43400 UPM, Selangor, Malaysia.
- Institute of Bioscience, Universiti Putra Malaysia, Serdang, 43400 UPM, Selangor, Malaysia.
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7
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Pruitt EL, Zhang R, Ross DH, Ashford NK, Chen X, Alonzo F, Bush MF, Werth BJ, Xu L. Elucidating the impact of bacterial lipases, human serum albumin, and FASII inhibition on the utilization of exogenous fatty acids by Staphylococcus aureus. mSphere 2023; 8:e0036823. [PMID: 38014966 PMCID: PMC10732024 DOI: 10.1128/msphere.00368-23] [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: 07/06/2023] [Accepted: 10/26/2023] [Indexed: 11/29/2023] Open
Abstract
IMPORTANCE Incorporation of host-derived exogenous fatty acids (eFAs), particularly unsaturated fatty acids (UFAs), by Staphylococcus aureus could affect the bacterial membrane fluidity and susceptibility to antimicrobials. In this work, we found that glycerol ester hydrolase (Geh) is the primary lipase hydrolyzing cholesteryl esters and, to a lesser extent, triglycerides and that human serum albumin (HSA) could serve as a buffer of eFAs, where low levels of HSA facilitate the utilization of eFAs but high levels of HSA inhibit it. The fact that the type II fatty acid synthesis (FASII) inhibitor, AFN-1252, leads to an increase in UFA content even in the absence of eFA suggests that membrane property modulation is part of its mechanism of action. Thus, Geh and/or the FASII system look to be promising targets to enhance S. aureus killing in a host environment by restricting eFA utilization or modulating membrane properties, respectively.
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Affiliation(s)
- Emily L. Pruitt
- Department of Chemistry, University of Washington, Seattle, Washington, USA
| | - Rutan Zhang
- Department of Medicinal Chemistry, University of Washington, Seattle, Washington, USA
| | - Dylan H. Ross
- Department of Medicinal Chemistry, University of Washington, Seattle, Washington, USA
| | | | - Xi Chen
- Department of Microbiology and Immunology, Loyola University Chicago-Stritch School of Medicine, Maywood, Illinois, USA
| | - Francis Alonzo
- Department of Microbiology and Immunology, Loyola University Chicago-Stritch School of Medicine, Maywood, Illinois, USA
| | - Matthew F. Bush
- Department of Chemistry, University of Washington, Seattle, Washington, USA
| | - Brian J. Werth
- Department of Pharmacy, University of Washington, Seattle, Washington, USA
| | - Libin Xu
- Department of Medicinal Chemistry, University of Washington, Seattle, Washington, USA
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8
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Robertson A, Sall J, Venzon M, Olivas JJ, Zheng X, Cammer M, Antao N, Zhou C, Devlin JC, Saes Thur R, Bethony J, Nejsum P, Shopsin B, Torres VJ, Liang FX, Cadwell K. Bacterial contact induces polar plug disintegration to mediate whipworm egg hatching. PLoS Pathog 2023; 19:e1011647. [PMID: 37738244 PMCID: PMC10550136 DOI: 10.1371/journal.ppat.1011647] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2023] [Revised: 10/04/2023] [Accepted: 08/30/2023] [Indexed: 09/24/2023] Open
Abstract
The bacterial microbiota promotes the life cycle of the intestine-dwelling whipworm Trichuris by mediating hatching of parasite eggs ingested by the mammalian host. Despite the enormous disease burden associated with Trichuris colonization, the mechanisms underlying this transkingdom interaction have been obscure. Here, we used a multiscale microscopy approach to define the structural events associated with bacteria-mediated hatching of eggs for the murine model parasite Trichuris muris. Through the combination of scanning electron microscopy (SEM) and serial block face SEM (SBFSEM), we visualized the outer surface morphology of the shell and generated 3D structures of the egg and larva during the hatching process. These images revealed that exposure to hatching-inducing bacteria catalyzed asymmetric degradation of the polar plugs prior to exit by the larva. Unrelated bacteria induced similar loss of electron density and dissolution of the structural integrity of the plugs. Egg hatching was most efficient when high densities of bacteria were bound to the poles. Consistent with the ability of taxonomically distant bacteria to induce hatching, additional results suggest chitinase released from larva within the eggs degrade the plugs from the inside instead of enzymes produced by bacteria in the external environment. These findings define at ultrastructure resolution the evolutionary adaptation of a parasite for the microbe-rich environment of the mammalian gut.
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Affiliation(s)
- Amicha Robertson
- Department of Microbiology, New York University Grossman School of Medicine, New York, New York, United States of America
| | - Joseph Sall
- Microscopy Laboratory, Division of Advanced Research Technologies, New York University Langone Health, New York, New York, United States of America
- Department of Cell Biology, New York University Grossman School of Medicine, New York New York, United States of America
| | - Mericien Venzon
- Department of Microbiology, New York University Grossman School of Medicine, New York, New York, United States of America
| | - Janet J. Olivas
- Department of Microbiology, New York University Grossman School of Medicine, New York, New York, United States of America
| | - Xuhui Zheng
- Department of Microbiology, New York University Grossman School of Medicine, New York, New York, United States of America
| | - Michael Cammer
- Microscopy Laboratory, Division of Advanced Research Technologies, New York University Langone Health, New York, New York, United States of America
- Department of Cell Biology, New York University Grossman School of Medicine, New York New York, United States of America
| | - Noelle Antao
- Department of Cell Biology, New York University Grossman School of Medicine, New York New York, United States of America
| | - Chunyi Zhou
- Department of Microbiology, New York University Grossman School of Medicine, New York, New York, United States of America
- Antimicrobial-Resistant Pathogens Program, New York University Langone Health, New York, New York, United States of America
- Department of Medicine, Division of Infectious Diseases, New York University Grossman School of Medicine, New York, New York, United States of America
| | - Joseph C. Devlin
- Department of Microbiology, New York University Grossman School of Medicine, New York, New York, United States of America
| | - Rafaela Saes Thur
- Department of Microbiology, Immunology and Tropical Medicine, George Washington University, Washington DC, United States of America
| | - Jeffrey Bethony
- Department of Microbiology, Immunology and Tropical Medicine, George Washington University, Washington DC, United States of America
| | - Peter Nejsum
- Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - Bo Shopsin
- Department of Microbiology, New York University Grossman School of Medicine, New York, New York, United States of America
- Antimicrobial-Resistant Pathogens Program, New York University Langone Health, New York, New York, United States of America
- Department of Medicine, Division of Infectious Diseases, New York University Grossman School of Medicine, New York, New York, United States of America
| | - Victor J. Torres
- Department of Microbiology, New York University Grossman School of Medicine, New York, New York, United States of America
- Antimicrobial-Resistant Pathogens Program, New York University Langone Health, New York, New York, United States of America
| | - Feng-Xia Liang
- Microscopy Laboratory, Division of Advanced Research Technologies, New York University Langone Health, New York, New York, United States of America
- Department of Cell Biology, New York University Grossman School of Medicine, New York New York, United States of America
| | - Ken Cadwell
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania, United States of America
- Department of Systems Pharmacology and Translational Therapeutics, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania, United States of America
- Department of Pathology and Laboratory Medicine, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania, United States of America
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9
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Pruitt EL, Zhang R, Ross DH, Ashford NK, Chen X, Alonzo F, Bush MF, Werth BJ, Xu L. Elucidating the Impact of Bacterial Lipases, Human Serum Albumin, and FASII Inhibition on the Utilization of Exogenous Fatty Acids by Staphylococcus aureus. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.06.29.547085. [PMID: 37425828 PMCID: PMC10327171 DOI: 10.1101/2023.06.29.547085] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/11/2023]
Abstract
Staphylococcus aureus only synthesizes straight-chain or branched-chain saturated fatty acids (SCFAs or BCFAs) via the type II fatty acid synthesis (FASII) pathway, but as a highly adaptive pathogen, S. aureus can also utilize host-derived exogenous fatty acids (eFAs), including SCFAs and unsaturated fatty acids (UFAs). S. aureus secretes three lipases, Geh, sal1, and SAUSA300_0641, which could perform the function of releasing fatty acids from host lipids. Once released, the FAs are phosphorylated by the fatty acid kinase, FakA, and incorporated into the bacterial lipids. In this study, we determined the substrate specificity of S. aureus secreted lipases, the effect of human serum albumin (HSA) on eFA incorporation, and the effect of FASII inhibitor, AFN-1252, on eFA incorporation using comprehensive lipidomics. When grown with major donors of fatty acids, cholesteryl esters (CEs) and triglycerides (TGs), Geh was found to be the primary lipase responsible for hydrolyzing CEs, but other lipases could compensate for the function of Geh in hydrolyzing TGs. Lipidomics showed that eFAs were incorporated into all major S. aureus lipid classes and that fatty acid-containing HSA can serve as a source of eFAs. Furthermore, S. aureus grown with UFAs displayed decreased membrane fluidity and increased production of reactive oxygen species (ROS). Exposure to AFN-1252 enhanced UFAs in the bacterial membrane, even without a source of eFAs, indicating a FASII pathway modification. Thus, the incorporation of eFAs alters the S. aureus lipidome, membrane fluidity, and ROS formation, which could affect host-pathogen interactions and susceptibility to membrane-targeting antimicrobials.
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Affiliation(s)
- Emily L. Pruitt
- Department of Chemistry, University of Washington, Seattle, Washington, USA
| | - Rutan Zhang
- Department of Medicinal Chemistry, University of Washington, Seattle, Washington, USA
| | - Dylan H. Ross
- Department of Medicinal Chemistry, University of Washington, Seattle, Washington, USA
| | | | - Xi Chen
- Department of Microbiology and Immunology, Loyola University Chicago-Stritch School of Medicine, Maywood, Illinois, USA
| | - Francis Alonzo
- Department of Microbiology and Immunology, Loyola University Chicago-Stritch School of Medicine, Maywood, Illinois, USA
| | - Matthew F. Bush
- Department of Chemistry, University of Washington, Seattle, Washington, USA
| | - Brian J. Werth
- Department of Pharmacy, University of Washington, Seattle, Washington, USA
| | - Libin Xu
- Department of Medicinal Chemistry, University of Washington, Seattle, Washington, USA
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10
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Wittekind MA, Briaud P, Smith JL, Tennant JR, Carroll RK. The Small Protein ScrA Influences Staphylococcus aureus Virulence-Related Processes via the SaeRS System. Microbiol Spectr 2023; 11:e0525522. [PMID: 37154710 PMCID: PMC10269730 DOI: 10.1128/spectrum.05255-22] [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: 12/21/2022] [Accepted: 04/11/2023] [Indexed: 05/10/2023] Open
Abstract
Staphylococcus aureus is a Gram-positive commensal and opportunistic pathogen able to cause diseases ranging from mild skin infections to life-threatening endocarditis and toxic shock syndrome. The ability to cause such an array of diseases is due to the complex S. aureus regulatory network controlling an assortment of virulence factors, including adhesins, hemolysins, proteases, and lipases. This regulatory network is controlled by both protein and RNA elements. We previously identified a novel regulatory protein called ScrA, which, when overexpressed, leads to the increased activity and expression of the SaeRS regulon. In this study, we further explore the role of ScrA and examine the consequences to the bacterial cell of scrA gene disruption. These results demonstrate that scrA is required for several virulence-related processes, and in many cases, the phenotypes of the scrA mutant are inverse to those observed in cells overexpressing ScrA. Interestingly, while the majority of ScrA-mediated phenotypes appear to rely on the SaeRS system, our results also indicate that ScrA may also act independently of SaeRS when regulating hemolytic activity. Finally, using a murine model of infection, we demonstrate that scrA is required for virulence, potentially in an organ-specific manner. IMPORTANCE Staphylococcus aureus is the cause of several potentially life-threatening infections. An assortment of toxins and virulence factors allows such a wide range of infections. However, an assortment of toxins or virulence factors requires complex regulation to control expression under all of the different conditions encountered by the bacterium. Understanding the intricate web of regulatory systems allows the development of novel approaches to combat S. aureus infections. Here, we have shown that the small protein ScrA, which was previously identified by our laboratory, influences several virulence-related functions through the SaeRS global regulatory system. These findings add ScrA to the growing list of virulence regulators in S. aureus.
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Affiliation(s)
| | - Paul Briaud
- Department of Biological Sciences, Ohio University, Athens, Ohio, USA
| | - Jayanna L. Smith
- Department of Biological Sciences, Ohio University, Athens, Ohio, USA
| | - Julia R. Tennant
- Department of Biological Sciences, Ohio University, Athens, Ohio, USA
| | - Ronan K. Carroll
- Department of Biological Sciences, Ohio University, Athens, Ohio, USA
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11
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Subramanian C, Frank MW, Yun MK, Rock CO. The Phospholipase A1 Activity of Glycerol Ester Hydrolase (Geh) Is Responsible for Extracellular 2-12( S)-Methyltetradecanoyl-Lysophosphatidylglycerol Production in Staphylococcus aureus. mSphere 2023; 8:e0003123. [PMID: 36976028 PMCID: PMC10117073 DOI: 10.1128/msphere.00031-23] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2023] [Accepted: 03/07/2023] [Indexed: 03/29/2023] Open
Abstract
Phosphatidylglycerol (PG) is the major membrane phospholipid of Staphylococcus aureus and predominately consists of molecular species with ≥16-carbon acyl chains in the 1-position and anteiso 12(S)-methyltetradecaonate (a15) esterified at the 2-position. The analysis of the growth media for PG-derived products shows S. aureus releases essentially pure 2-12(S)-methyltetradecanoyl-sn-glycero-3-phospho-1'-sn-glycerol (a15:0-LPG) derived from the hydrolysis of the 1-position of PG into the environment. The cellular lysophosphatidylglycerol (LPG) pool is dominated by a15-LPG but also consists of ≥16-LPG species arising from the removal of the 2-position. Mass tracing experiments confirmed a15-LPG was derived from isoleucine metabolism. A screen of candidate secreted lipase knockout strains pinpointed glycerol ester hydrolase (geh) as the gene required for generating extracellular a15-LPG, and complementation of a Δgeh strain with a Geh expression plasmid restored extracellular a15-LPG formation. Orlistat, a covalent inhibitor of Geh, also attenuated extracellular a15-LPG accumulation. Purified Geh hydrolyzed the 1-position acyl chain of PG and generated only a15-LPG from a S. aureus lipid mixture. The Geh product was 2-a15-LPG, which spontaneously isomerizes with time to a mixture of 1- and 2-a15-LPG. Docking PG in the Geh active site provides a structural rationale for the positional specificity of Geh. These data demonstrate a physiological role for Geh phospholipase A1 activity in S. aureus membrane phospholipid turnover. IMPORTANCE Glycerol ester hydrolase, Geh, is an abundant secreted lipase whose expression is controlled by the accessory gene regulator (Agr) quorum-sensing signal transduction pathway. Geh is thought to have a role in virulence based on its ability to hydrolyze host lipids at the infection site to provide fatty acids for membrane biogenesis and substrates for oleate hydratase, and Geh inhibits immune cell activation by hydrolyzing lipoprotein glycerol esters. The discovery that Geh is the major contributor to the formation and release of a15-LPG reveals an unappreciated physiological role for Geh acting as a phospholipase A1 in the degradation of S. aureus membrane phosphatidylglycerol. The role(s) for extracellular a15-LPG in S. aureus biology remain to be elucidated.
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Affiliation(s)
- Chitra Subramanian
- Department of Infectious Diseases, St. Jude Children’s Research Hospital, Memphis, Tennessee, USA
| | - Matthew W. Frank
- Department of Infectious Diseases, St. Jude Children’s Research Hospital, Memphis, Tennessee, USA
| | - My-Kyung Yun
- Department of Infectious Diseases, St. Jude Children’s Research Hospital, Memphis, Tennessee, USA
| | - Charles O. Rock
- Department of Infectious Diseases, St. Jude Children’s Research Hospital, Memphis, Tennessee, USA
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12
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Robertson A, Sall J, Venzon M, Olivas JJ, Zheng X, Cammer M, Antao N, Thur RS, Bethony J, Nejsum P, Torres VJ, Liang FX, Cadwell K. Bacterial contact induces polar plug disintegration to mediate whipworm egg hatching. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.03.13.532458. [PMID: 36993552 PMCID: PMC10054943 DOI: 10.1101/2023.03.13.532458] [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: 06/19/2023]
Abstract
The bacterial microbiota promotes the life cycle of the intestine-dwelling whipworm Trichuris by mediating hatching of parasite eggs ingested by the mammalian host. Despite the enormous disease burden associated with Trichuris colonization, the mechanisms underlying this transkingdom interaction have been obscure. Here, we used a multiscale microscopy approach to define the structural events associated with bacteria-mediated hatching of eggs for the murine model parasite Trichuris muris . Through the combination of scanning electron microscopy (SEM) and serial block face SEM (SBFSEM), we visualized the outer surface morphology of the shell and generated 3D structures of the egg and larva during the hatching process. These images revealed that exposure to hatching-inducing bacteria catalyzed asymmetric degradation of the polar plugs prior to exit by the larva. Although unrelated bacteria induced similar loss of electron density and dissolution of the structural integrity of the plugs, egg hatching was most efficient in the presence of bacteria that bound poles with high density such as Staphylococcus aureus . Consistent with the ability of taxonomically distant bacteria to induce hatching, additional results suggest chitinase released from larva within the eggs degrade the plugs from the inside instead of enzymes produced by bacteria in the external environment. These findings define at ultrastructure resolution the evolutionary adaptation of a parasite for the microbe-rich environment of the mammalian gut.
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Affiliation(s)
- Amicha Robertson
- Department of Microbiology, New York University Grossman School of Medicine, New York, NY 10016, USA
| | - Joseph Sall
- Microscopy Laboratory, Division of Advanced Research Technologies, New York University Langone Health, New York, NY 10016, USA
- Department of Cell Biology, NYU Grossman School of Medicine, New York, NY 10016, USA
| | - Mericien Venzon
- Department of Microbiology, New York University Grossman School of Medicine, New York, NY 10016, USA
| | - Janet J. Olivas
- Department of Microbiology, New York University Grossman School of Medicine, New York, NY 10016, USA
| | - Xuhui Zheng
- Department of Microbiology, New York University Grossman School of Medicine, New York, NY 10016, USA
| | - Michael Cammer
- Microscopy Laboratory, Division of Advanced Research Technologies, New York University Langone Health, New York, NY 10016, USA
- Department of Cell Biology, NYU Grossman School of Medicine, New York, NY 10016, USA
| | - Noelle Antao
- Department of Cell Biology, NYU Grossman School of Medicine, New York, NY 10016, USA
| | - Rafaela Saes Thur
- Department of Microbiology, Immunology and Tropical Medicine, George Washington University, Washington, DC 20052, USA
| | - Jeffrey Bethony
- Department of Microbiology, Immunology and Tropical Medicine, George Washington University, Washington, DC 20052, USA
| | - Peter Nejsum
- Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - Victor J. Torres
- Department of Microbiology, New York University Grossman School of Medicine, New York, NY 10016, USA
- Antimicrobial-Resistant Pathogens Program, NYU Langone Health, New York, NY 10016, USA
| | - Feng-Xia Liang
- Microscopy Laboratory, Division of Advanced Research Technologies, New York University Langone Health, New York, NY 10016, USA
- Department of Cell Biology, NYU Grossman School of Medicine, New York, NY 10016, USA
| | - Ken Cadwell
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104
- Department of Systems Pharmacology and Translational Therapeutics, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104
- Department of Pathology and Laboratory Medicine, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104
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13
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Francis D, Bhairaddy A, Joy A, Hari GV, Francis A. Secretory proteins in the orchestration of microbial virulence: The curious case of Staphylococcus aureus. ADVANCES IN PROTEIN CHEMISTRY AND STRUCTURAL BIOLOGY 2023; 133:271-350. [PMID: 36707204 DOI: 10.1016/bs.apcsb.2022.10.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Microbial virulence showcases an excellent model for adaptive changes that enable an organism to survive and proliferate in a hostile environment and exploit host resources to its own benefit. In Staphylococcus aureus, an opportunistic pathogen of the human host, known for the diversity of the disease conditions it inflicts and the rapid evolution of antibiotic resistance, virulence is a consequence of having a highly plastic genome that is amenable to quick reprogramming and the ability to express a diverse arsenal of virulence factors. Virulence factors that are secreted to the host milieu effectively manipulate the host conditions to favor bacterial survival and growth. They assist in colonization, nutrient acquisition, immune evasion, and systemic spread. The structural and functional characteristics of the secreted virulence proteins have been shaped to assist S. aureus in thriving and disseminating effectively within the host environment and exploiting the host resources to its best benefit. With the aim of highlighting the importance of secreted virulence proteins in bacterial virulence, the present chapter provides a comprehensive account of the role of the major secreted proteins of S. aureus in orchestrating its virulence in the human host.
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Affiliation(s)
- Dileep Francis
- Department of Life Sciences, Kristu Jayanti College, Autonomous, Bengaluru, Karnataka, India.
| | - Anusha Bhairaddy
- Department of Life Sciences, Kristu Jayanti College, Autonomous, Bengaluru, Karnataka, India
| | - Atheene Joy
- Department of Life Sciences, Kristu Jayanti College, Autonomous, Bengaluru, Karnataka, India
| | | | - Ashik Francis
- Rajiv Gandhi Centre for Biotechnology, Trivandrum, Kerala, India
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14
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Dab A, Hasnaoui I, Mechri S, Allala F, Bouacem K, Noiriel A, Bouanane-Darenfed A, Saalaoui E, Asehraou A, Wang F, Abousalham A, Jaouadi B. Biochemical characterization of an alkaline and detergent-stable Lipase from Fusarium annulatum Bugnicourt strain CBS associated with olive tree dieback. PLoS One 2023; 18:e0286091. [PMID: 37205651 DOI: 10.1371/journal.pone.0286091] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2023] [Accepted: 05/07/2023] [Indexed: 05/21/2023] Open
Abstract
This work describes a novel extracellular lipolytic carboxylester hydrolase named FAL, with lipase and phospholipase A1 (PLA1) activity, from a newly isolated filamentous fungus Ascomycota CBS strain, identified as Fusarium annulatum Bunigcourt. FAL was purified to about 62-fold using ammonium sulphate precipitation, Superdex® 200 Increase gel filtration and Q-Sepharose Fast Flow columns, with a total yield of 21%. The specific activity of FAL was found to be 3500 U/mg at pH 9 and 40°C and 5000 U/mg at pH 11 and 45°C, on emulsions of triocanoin and egg yolk phosphatidylcholine, respectively. SDS-PAGE and zymography analysis estimated the molecular weight of FAL to be 33 kDa. FAL was shown to be a PLA1 with a regioselectivity to the sn-1 position of surface-coated phospholipids esterified with α-eleostearic acid. FAL is a serine enzyme since its activity on triglycerides and phospholipids was completely inhibited by the lipase inhibitor Orlistat (40 μM). Interestingly, compared to Fusarium graminearum lipase (GZEL) and the Thermomyces lanuginosus lipase (Lipolase®), this novel fungal (phospho)lipase showed extreme tolerance to the presence of non-polar organic solvents, non-ionic and anionic surfactants, and oxidants, in addition to significant compatibility and stability with some available laundry detergents. The analysis of washing performance showed that it has the capability to efficiently eliminate oil-stains. Overall, FAL could be an ideal choice for application in detergents.
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Affiliation(s)
- Ahlem Dab
- Institut de Chimie et de Biochimie Moléculaires et Supramoléculaires (ICBMS), Université Lyon, Université Lyon 1, UMR 5246 CNRS, Génie Enzymatique, Membranes Biomimétiques et Assemblages Supramoléculaires (GEMBAS), Villeurbanne, France
- Laboratoire de Biotechnologie Microbienne et d'Ingénierie des Enzymes (LBMIE), Centre de Biotechnologie de Sfax (CBS), Université de Sfax, Sfax, Tunisia
| | - Ismail Hasnaoui
- Institut de Chimie et de Biochimie Moléculaires et Supramoléculaires (ICBMS), Université Lyon, Université Lyon 1, UMR 5246 CNRS, Génie Enzymatique, Membranes Biomimétiques et Assemblages Supramoléculaires (GEMBAS), Villeurbanne, France
- Faculté des Sciences d'Oujda (FSO), Laboratoire de Bioressources, Biotechnologie, Ethnopharmacologie et Santé (LBBES), Université Mohammed Premier (UMP), Oujda, Morocco
| | - Sondes Mechri
- Laboratoire de Biotechnologie Microbienne et d'Ingénierie des Enzymes (LBMIE), Centre de Biotechnologie de Sfax (CBS), Université de Sfax, Sfax, Tunisia
| | - Fawzi Allala
- Faculté des Sciences Biologiques (FSB), Laboratoire de Biologie Cellulaire et Moléculaire (LCMB), Equipe de Microbiologie, Université des Sciences et de la Technologie Houari Boumediene (USTHB), El Alia, Bab Ezzouar, Alger, Algeria
| | - Khelifa Bouacem
- Faculté des Sciences Biologiques (FSB), Laboratoire de Biologie Cellulaire et Moléculaire (LCMB), Equipe de Microbiologie, Université des Sciences et de la Technologie Houari Boumediene (USTHB), El Alia, Bab Ezzouar, Alger, Algeria
| | - Alexandre Noiriel
- Institut de Chimie et de Biochimie Moléculaires et Supramoléculaires (ICBMS), Université Lyon, Université Lyon 1, UMR 5246 CNRS, Génie Enzymatique, Membranes Biomimétiques et Assemblages Supramoléculaires (GEMBAS), Villeurbanne, France
| | - Amel Bouanane-Darenfed
- Faculté des Sciences Biologiques (FSB), Laboratoire de Biologie Cellulaire et Moléculaire (LCMB), Equipe de Microbiologie, Université des Sciences et de la Technologie Houari Boumediene (USTHB), El Alia, Bab Ezzouar, Alger, Algeria
| | - Ennouamane Saalaoui
- Faculté des Sciences d'Oujda (FSO), Laboratoire de Bioressources, Biotechnologie, Ethnopharmacologie et Santé (LBBES), Université Mohammed Premier (UMP), Oujda, Morocco
| | - Abdeslam Asehraou
- Faculté des Sciences d'Oujda (FSO), Laboratoire de Bioressources, Biotechnologie, Ethnopharmacologie et Santé (LBBES), Université Mohammed Premier (UMP), Oujda, Morocco
| | - Fanghua Wang
- School of Food Science and Engineering (SFSE), South China University of Technology (SCUT), Guangzhou, China
| | - Abdelkarim Abousalham
- Institut de Chimie et de Biochimie Moléculaires et Supramoléculaires (ICBMS), Université Lyon, Université Lyon 1, UMR 5246 CNRS, Génie Enzymatique, Membranes Biomimétiques et Assemblages Supramoléculaires (GEMBAS), Villeurbanne, France
| | - Bassem Jaouadi
- Laboratoire de Biotechnologie Microbienne et d'Ingénierie des Enzymes (LBMIE), Centre de Biotechnologie de Sfax (CBS), Université de Sfax, Sfax, Tunisia
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15
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Bakker A, Kotsogianni I, Mirenda L, Straub VM, Avalos M, van den Berg RJBH, Florea BI, van Wezel GP, Janssen APA, Martin NI, van der Stelt M. Chemical Proteomics Reveals Antibiotic Targets of Oxadiazolones in MRSA. J Am Chem Soc 2022; 145:1136-1143. [PMID: 36584241 PMCID: PMC9853856 DOI: 10.1021/jacs.2c10819] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Phenotypic screening is a powerful approach to identify novel antibiotics, but elucidation of the targets responsible for the antimicrobial activity is often challenging in the case of compounds with a polypharmacological mode of action. Here, we show that activity-based protein profiling maps the target interaction landscape of a series of 1,3,4-oxadiazole-3-ones identified in a phenotypic screen to have high antibacterial potency against multidrug-resistant Staphylococcus aureus. In situ competitive and comparative chemical proteomics with a tailor-made activity-based probe, in combination with transposon and resistance studies, revealed several cysteine and serine hydrolases as relevant targets. Our data showcase oxadiazolones as a novel antibacterial chemotype with a polypharmacological mode of action, in which FabH, FphC, and AdhE play a central role.
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Affiliation(s)
- Alexander
T. Bakker
- Department
of Molecular Physiology, Leiden Institute of Chemistry, Leiden University, Leiden 2300 RA, The Netherlands
| | - Ioli Kotsogianni
- Biological
Chemistry Group, Institute of Biology Leiden, Leiden University, Leiden 2333 BE, The Netherlands
| | - Liza Mirenda
- Department
of Molecular Physiology, Leiden Institute of Chemistry, Leiden University, Leiden 2300 RA, The Netherlands
| | - Verena M. Straub
- Department
of Molecular Physiology, Leiden Institute of Chemistry, Leiden University, Leiden 2300 RA, The Netherlands
| | - Mariana Avalos
- Department
of Molecular Biotechnology, Institute of Biology Leiden, Leiden University, Leiden 2333 BE, The Netherlands
| | | | - Bogdan I. Florea
- Department
of Molecular Physiology, Leiden Institute of Chemistry, Leiden University, Leiden 2300 RA, The Netherlands
| | - Gilles P. van Wezel
- Department
of Molecular Biotechnology, Institute of Biology Leiden, Leiden University, Leiden 2333 BE, The Netherlands
| | - Antonius P. A. Janssen
- Department
of Molecular Physiology, Leiden Institute of Chemistry, Leiden University, Leiden 2300 RA, The Netherlands
| | - Nathaniel I. Martin
- Biological
Chemistry Group, Institute of Biology Leiden, Leiden University, Leiden 2333 BE, The Netherlands,
| | - Mario van der Stelt
- Department
of Molecular Physiology, Leiden Institute of Chemistry, Leiden University, Leiden 2300 RA, The Netherlands,
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