1
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Peng W, Giesbers KC, Šiborová M, Beugelink JW, Pronker MF, Schulte D, Hilkens J, Janssen BJ, Strijbis K, Snijder J. Reverse-engineering the anti-MUC1 antibody 139H2 by mass spectrometry-based de novo sequencing. Life Sci Alliance 2024; 7:e202302366. [PMID: 38508723 PMCID: PMC10955041 DOI: 10.26508/lsa.202302366] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2023] [Revised: 03/11/2024] [Accepted: 03/12/2024] [Indexed: 03/22/2024] Open
Abstract
Mucin 1 (MUC1) is a transmembrane mucin expressed at the apical surface of epithelial cells at mucosal surfaces. MUC1 has a barrier function against bacterial invasion and is well known for its aberrant expression and glycosylation in adenocarcinomas. The MUC1 extracellular domain contains a variable number of tandem repeats (VNTR) of 20 amino acids, which are heavily O-linked glycosylated. Monoclonal antibodies against the MUC1 VNTR are powerful research tools with applications in the diagnosis and treatment of MUC1-expressing cancers. Here, we report direct mass spectrometry-based sequencing of anti-MUC1 hybridoma-derived 139H2 IgG, enabling reverse-engineering of the functional recombinant monoclonal antibody. The crystal structure of the 139H2 Fab fragment in complex with the MUC1 epitope was solved, revealing the molecular basis of 139H2 binding specificity to MUC1 and its tolerance to O-glycosylation of the VNTR. The available sequence of 139H2 will allow further development of MUC1-related diagnostic, targeting, and treatment strategies.
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Affiliation(s)
- Weiwei Peng
- https://ror.org/04pp8hn57 Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute of Pharmaceutical Sciences, Utrecht University, Utrecht, Netherlands
| | - Koen Cap Giesbers
- https://ror.org/04pp8hn57 Department of Biomolecular Health Sciences, Division of Infectious Diseases and Immunology, Faculty of Veterinary Medicine, Utrecht University, Utrecht, Netherlands
| | - Marta Šiborová
- https://ror.org/04pp8hn57 Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute of Pharmaceutical Sciences, Utrecht University, Utrecht, Netherlands
| | - J Wouter Beugelink
- https://ror.org/04pp8hn57 Structural Biochemistry, Bijvoet Center for Biomolecular Research, Department of Chemistry, Faculty of Science, Utrecht University, Utrecht, Netherlands
| | - Matti F Pronker
- https://ror.org/04pp8hn57 Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute of Pharmaceutical Sciences, Utrecht University, Utrecht, Netherlands
| | - Douwe Schulte
- https://ror.org/04pp8hn57 Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute of Pharmaceutical Sciences, Utrecht University, Utrecht, Netherlands
| | - John Hilkens
- Division of Molecular Genetics, The Netherlands Cancer Institute, Amsterdam, Netherlands
| | - Bert Jc Janssen
- https://ror.org/04pp8hn57 Structural Biochemistry, Bijvoet Center for Biomolecular Research, Department of Chemistry, Faculty of Science, Utrecht University, Utrecht, Netherlands
| | - Karin Strijbis
- https://ror.org/04pp8hn57 Department of Biomolecular Health Sciences, Division of Infectious Diseases and Immunology, Faculty of Veterinary Medicine, Utrecht University, Utrecht, Netherlands
| | - Joost Snijder
- https://ror.org/04pp8hn57 Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute of Pharmaceutical Sciences, Utrecht University, Utrecht, Netherlands
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2
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van Teijlingen NH, van Smoorenburg MY, Sarrami-Forooshani R, Zijlstra-Willems EM, van Hamme JL, Borgdorff H, van de Wijgert JH, van Leeuwen E, van der Post JAM, Strijbis K, Ribeiro CMS, Geijtenbeek TBH. Prevotella timonensis bacteria associated with vaginal dysbiosis enhance HIV-1 susceptibility of vaginal CD4+ T cells. J Infect Dis 2024:jiae166. [PMID: 38573164 DOI: 10.1093/infdis/jiae166] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2023] [Revised: 03/06/2024] [Accepted: 03/28/2024] [Indexed: 04/05/2024] Open
Abstract
Dysbiosis of the vaginal microbiome poses a serious risk for sexual HIV-1 transmission. Prevotella spp. are abundant during vaginal dysbiosis and associated with enhanced HIV-1 susceptibility; however, underlying mechanisms remain unclear. Here, we investigated the direct effect of vaginal bacteria on HIV-1 susceptibility of vaginal CD4+ T cells. Notably, pre-exposure to Prevotella timonensis enhanced HIV-1 uptake by vaginal T cells, leading to increased viral fusion and enhanced virus production. Pre-exposure to antiretroviral inhibitors abolished Prevotella timonensis-enhanced infection. Hence, our study shows that the vaginal microbiome directly affects mucosal CD4+ T cell susceptibility, emphasising importance of vaginal dysbiosis diagnosis and treatment.
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Affiliation(s)
- Nienke H van Teijlingen
- Amsterdam UMC, location University of Amsterdam, Department of Experimental Immunology, Meibergdreef 9, Amsterdam, the Netherlands
- Amsterdam institute for Immunology and Infectious Diseases, Amsterdam, the Netherlands
- Department of Obstetrics and Gynecology, Amsterdam UMC Location University of Amsterdam, Amsterdam, The Netherlands
| | - Marleen Y van Smoorenburg
- Amsterdam UMC, location University of Amsterdam, Department of Experimental Immunology, Meibergdreef 9, Amsterdam, the Netherlands
- Amsterdam institute for Immunology and Infectious Diseases, Amsterdam, the Netherlands
| | - Ramin Sarrami-Forooshani
- Amsterdam UMC, location University of Amsterdam, Department of Experimental Immunology, Meibergdreef 9, Amsterdam, the Netherlands
- ATMP Department, Breast Cancer Research Center, Motamed Cancer Institute, ACECR, Tehran, Iran
| | - Esther M Zijlstra-Willems
- Amsterdam UMC, location University of Amsterdam, Department of Experimental Immunology, Meibergdreef 9, Amsterdam, the Netherlands
- Amsterdam institute for Immunology and Infectious Diseases, Amsterdam, the Netherlands
| | - John L van Hamme
- Amsterdam UMC, location University of Amsterdam, Department of Experimental Immunology, Meibergdreef 9, Amsterdam, the Netherlands
- Amsterdam institute for Immunology and Infectious Diseases, Amsterdam, the Netherlands
| | - Hanneke Borgdorff
- Amsterdam Institute for Global Health and Development (AIGHD), Amsterdam, The Netherlands
- Department of Public Health and Primary Care, Leiden University Medical Center, Leiden, The Netherlands
| | - Janneke Hhm van de Wijgert
- Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Elisabeth van Leeuwen
- Department of Obstetrics and Gynecology, Amsterdam UMC Location University of Amsterdam, Amsterdam, The Netherlands
| | - Joris A M van der Post
- Department of Obstetrics and Gynecology, Amsterdam UMC Location University of Amsterdam, Amsterdam, The Netherlands
| | - Karin Strijbis
- Department of Biomolecular Health Sciences, Division Infectious Diseases and Immunology, Faculty of Veterinary Medicine, University of Utrecht, Utrecht, The Netherlands
| | - Carla M S Ribeiro
- Amsterdam UMC, location University of Amsterdam, Department of Experimental Immunology, Meibergdreef 9, Amsterdam, the Netherlands
- Amsterdam institute for Immunology and Infectious Diseases, Amsterdam, the Netherlands
| | - Teunis B H Geijtenbeek
- Amsterdam UMC, location University of Amsterdam, Department of Experimental Immunology, Meibergdreef 9, Amsterdam, the Netherlands
- Amsterdam institute for Immunology and Infectious Diseases, Amsterdam, the Netherlands
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3
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Segui-Perez C, Stapels DAC, Ma Z, Su J, Passchier E, Westendorp B, Wubbolts RW, Wu W, van Putten JPM, Strijbis K. MUC13 negatively regulates tight junction proteins and intestinal epithelial barrier integrity via protein kinase C. J Cell Sci 2024; 137:jcs261468. [PMID: 38345099 PMCID: PMC10984281 DOI: 10.1242/jcs.261468] [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] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2023] [Accepted: 01/29/2024] [Indexed: 03/14/2024] Open
Abstract
Glycosylated mucin proteins contribute to the essential barrier function of the intestinal epithelium. The transmembrane mucin MUC13 is an abundant intestinal glycoprotein with important functions for mucosal maintenance that are not yet completely understood. We demonstrate that in human intestinal epithelial monolayers, MUC13 localized to both the apical surface and the tight junction (TJ) region on the lateral membrane. MUC13 deletion resulted in increased transepithelial resistance (TEER) and reduced translocation of small solutes. TEER buildup in ΔMUC13 cells could be prevented by addition of MLCK, ROCK or protein kinase C (PKC) inhibitors. The levels of TJ proteins including claudins and occludin were highly increased in membrane fractions of MUC13 knockout cells. Removal of the MUC13 cytoplasmic tail (CT) also altered TJ composition but did not affect TEER. The increased buildup of TJ complexes in ΔMUC13 and MUC13-ΔCT cells was dependent on PKC. The responsible PKC member might be PKCδ (or PRKCD) based on elevated protein levels in the absence of full-length MUC13. Our results demonstrate for the first time that a mucin protein can negatively regulate TJ function and stimulate intestinal barrier permeability.
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Affiliation(s)
- Celia Segui-Perez
- Department of Biomolecular Health Sciences, Division of Infectious Diseases and Immunology, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 1, 3584 CL Utrecht, the Netherlands
| | - Daphne A. C. Stapels
- Department of Biomolecular Health Sciences, Division of Infectious Diseases and Immunology, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 1, 3584 CL Utrecht, the Netherlands
| | - Ziliang Ma
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Padualaan 8, 3584 CH Utrecht, the Netherlands
- Singapore Immunology Network (SIgN), Agency for Science, Technology, and Research (A*STAR), 138648 Singapore, Singapore
- Department of Pharmacy, National University of Singapore, 117543 Singapore, Singapore
| | - Jinyi Su
- Department of Biomolecular Health Sciences, Division of Infectious Diseases and Immunology, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 1, 3584 CL Utrecht, the Netherlands
| | - Elsemieke Passchier
- UMAB, Department of Laboratory Pharmacy and Biomedical Genetics, Center for Translational Immunology, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX Utrecht, the Netherlands
| | - Bart Westendorp
- Department of Biomolecular Health Sciences, Division of Cell Biology, Metabolism and Cancer, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 1, 3584 CL Utrecht, the Netherlands
| | - Richard W. Wubbolts
- Department of Biomolecular Health Sciences, Division of Cell Biology, Metabolism and Cancer, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 1, 3584 CL Utrecht, the Netherlands
| | - Wei Wu
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Padualaan 8, 3584 CH Utrecht, the Netherlands
- Singapore Immunology Network (SIgN), Agency for Science, Technology, and Research (A*STAR), 138648 Singapore, Singapore
- Department of Pharmacy, National University of Singapore, 117543 Singapore, Singapore
| | - Jos P. M. van Putten
- Department of Biomolecular Health Sciences, Division of Infectious Diseases and Immunology, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 1, 3584 CL Utrecht, the Netherlands
| | - Karin Strijbis
- Department of Biomolecular Health Sciences, Division of Infectious Diseases and Immunology, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 1, 3584 CL Utrecht, the Netherlands
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4
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Mavrogeni ME, Asadpoor M, Judernatz JH, van Ark I, Wösten MMSM, Strijbis K, Pieters RJ, Folkerts G, Braber S. Protective Effects of Alginate and Chitosan Oligosaccharides against Clostridioides difficile Bacteria and Toxin. Toxins (Basel) 2023; 15:586. [PMID: 37888617 PMCID: PMC10610568 DOI: 10.3390/toxins15100586] [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] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2022] [Revised: 09/01/2023] [Accepted: 09/12/2023] [Indexed: 10/28/2023] Open
Abstract
Clostridioides difficile infection is expected to become the most common healthcare-associated infection worldwide. C. difficile-induced pathogenicity is significantly attributed to its enterotoxin, TcdA, which primarily targets Rho-GTPases involved in regulating cytoskeletal and tight junction (TJ) dynamics, thus leading to cytoskeleton breakdown and ultimately increased intestinal permeability. This study investigated whether two non-digestible oligosaccharides (NDOs), alginate (AOS) and chitosan (COS) oligosaccharides, possess antipathogenic and barrier-protective properties against C. difficile bacteria and TcdA toxin, respectively. Both NDOs significantly reduced C. difficile growth, while cell cytotoxicity assays demonstrated that neither COS nor AOS significantly attenuated the TcdA-induced cell death 24 h post-exposure. The challenge of Caco-2 monolayers with increasing TcdA concentrations increased paracellular permeability, as measured by TEER and LY flux assays. In this experimental setup, COS completely abolished, and AOS mitigated, the deleterious effects of TcdA on the monolayer's integrity. These events were not accompanied by alterations in ZO-1 and occludin protein levels; however, immunofluorescence microscopy revealed that both AOS and COS prevented the TcdA-induced occludin mislocalization. Finally, both NDOs accelerated TJ reassembly upon a calcium-switch assay. Overall, this study established the antipathogenic and barrier-protective capacity of AOS and COS against C. difficile and its toxin, TcdA, while revealing their ability to promote TJ reassembly in Caco-2 cells.
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Affiliation(s)
- Maria Eleni Mavrogeni
- Division of Pharmacology, Utrecht Institute for Pharmaceutical Sciences, Faculty of Science, Utrecht University, Universiteitsweg 99, 3584 CG Utrecht, The Netherlands
| | - Mostafa Asadpoor
- Division of Pharmacology, Utrecht Institute for Pharmaceutical Sciences, Faculty of Science, Utrecht University, Universiteitsweg 99, 3584 CG Utrecht, The Netherlands
| | - Jo H Judernatz
- Structural Biochemistry Group, Bijvoet Centre for Biomolecular Research, Utrecht University, Universiteitsweg 99, 3584 CG Utrecht, The Netherlands
| | - Ingrid van Ark
- Division of Pharmacology, Utrecht Institute for Pharmaceutical Sciences, Faculty of Science, Utrecht University, Universiteitsweg 99, 3584 CG Utrecht, The Netherlands
| | - Marc M S M Wösten
- Division of Infectious Diseases and Immunology, Department of Biomolecular Health Sciences, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 1, 3584 CL Utrecht, The Netherlands
| | - Karin Strijbis
- Division of Infectious Diseases and Immunology, Department of Biomolecular Health Sciences, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 1, 3584 CL Utrecht, The Netherlands
| | - Roland J Pieters
- Division of Medicinal Chemistry and Chemical Biology, Utrecht Institute for Pharmaceutical Sciences, Faculty of Science, Utrecht University, Universiteitsweg 99, 3584 CG Utrecht, The Netherlands
| | - Gert Folkerts
- Division of Pharmacology, Utrecht Institute for Pharmaceutical Sciences, Faculty of Science, Utrecht University, Universiteitsweg 99, 3584 CG Utrecht, The Netherlands
| | - Saskia Braber
- Division of Pharmacology, Utrecht Institute for Pharmaceutical Sciences, Faculty of Science, Utrecht University, Universiteitsweg 99, 3584 CG Utrecht, The Netherlands
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5
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Chatterjee M, Huang LZX, Mykytyn AZ, Wang C, Lamers MM, Westendorp B, Wubbolts RW, van Putten JPM, Bosch BJ, Haagmans BL, Strijbis K. Glycosylated extracellular mucin domains protect against SARS-CoV-2 infection at the respiratory surface. PLoS Pathog 2023; 19:e1011571. [PMID: 37561789 PMCID: PMC10464970 DOI: 10.1371/journal.ppat.1011571] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2023] [Revised: 08/29/2023] [Accepted: 07/21/2023] [Indexed: 08/12/2023] Open
Abstract
Mucins play an essential role in protecting the respiratory tract against microbial infections while also acting as binding sites for bacterial and viral adhesins. The heavily O-glycosylated gel-forming mucins MUC5AC and MUC5B eliminate pathogens by mucociliary clearance. Transmembrane mucins MUC1, MUC4, and MUC16 can restrict microbial invasion at the apical surface of the epithelium. In this study, we determined the impact of host mucins and mucin glycans on epithelial entry of SARS-CoV-2. Human lung epithelial Calu-3 cells express the SARS-CoV-2 entry receptor ACE2 and high levels of glycosylated MUC1, but not MUC4 and MUC16, on their cell surface. The O-glycan-specific mucinase StcE specifically removed the glycosylated part of the MUC1 extracellular domain while leaving the underlying SEA domain and cytoplasmic tail intact. StcE treatment of Calu-3 cells significantly enhanced infection with SARS-CoV-2 pseudovirus and authentic virus, while removal of terminal mucin glycans sialic acid and fucose from the epithelial surface did not impact viral entry. In Calu-3 cells, the transmembrane mucin MUC1 and ACE2 are located to the apical surface in close proximity and StcE treatment results in enhanced binding of purified spike protein. Both MUC1 and MUC16 are expressed on the surface of human organoid-derived air-liquid interface (ALI) differentiated airway cultures and StcE treatment led to mucin removal and increased levels of SARS-CoV-2 replication. In these cultures, MUC1 was highly expressed in non-ciliated cells while MUC16 was enriched in goblet cells. In conclusion, the glycosylated extracellular domains of different transmembrane mucins might have similar protective functions in different respiratory cell types by restricting SARS-CoV-2 binding and entry.
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Affiliation(s)
- Maitrayee Chatterjee
- Department of Biomolecular Health Sciences, Division Infectious Diseases and Immunology, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
| | - Liane Z. X. Huang
- Department of Biomolecular Health Sciences, Division Infectious Diseases and Immunology, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
| | - Anna Z. Mykytyn
- Viroscience Department, Erasmus Medical Center, Rotterdam, The Netherlands
| | - Chunyan Wang
- Department of Biomolecular Health Sciences, Division Infectious Diseases and Immunology, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
| | - Mart M. Lamers
- Viroscience Department, Erasmus Medical Center, Rotterdam, The Netherlands
| | - Bart Westendorp
- Department of Biomolecular Health Sciences, Division Cell Biology, Metabolism and Cancer, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
| | | | - Jos P. M. van Putten
- Department of Biomolecular Health Sciences, Division Infectious Diseases and Immunology, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
| | - Berend-Jan Bosch
- Department of Biomolecular Health Sciences, Division Infectious Diseases and Immunology, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
| | - Bart L. Haagmans
- Viroscience Department, Erasmus Medical Center, Rotterdam, The Netherlands
| | - Karin Strijbis
- Department of Biomolecular Health Sciences, Division Infectious Diseases and Immunology, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
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6
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Madunić K, Luijkx YMCA, Mayboroda OA, Janssen GMC, van Veelen PA, Strijbis K, Wennekes T, Lageveen-Kammeijer GSM, Wuhrer M. O-Glycomic and Proteomic Signatures of Spontaneous and Butyrate-Stimulated Colorectal Cancer Cell Line Differentiation. Mol Cell Proteomics 2023; 22:100501. [PMID: 36669592 PMCID: PMC9999233 DOI: 10.1016/j.mcpro.2023.100501] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2022] [Revised: 01/08/2023] [Accepted: 01/11/2023] [Indexed: 01/19/2023] Open
Abstract
Gut microbiota of the gastrointestinal tract provide health benefits to the human host via bacterial metabolites. Bacterial butyrate has beneficial effects on intestinal homeostasis and is the preferred energy source of intestinal epithelial cells, capable of inducing differentiation. It was previously observed that changes in the expression of specific proteins as well as protein glycosylation occur with differentiation. In this study, specific mucin O-glycans were identified that mark butyrate-induced epithelial differentiation of the intestinal cell line CaCo-2 (Cancer Coli-2), by applying porous graphitized carbon nano-liquid chromatography with electrospray ionization tandem mass spectrometry. Moreover, a quantitative proteomic approach was used to decipher changes in the cell proteome. It was found that the fully differentiated butyrate-stimulated cells are characterized by a higher expression of sialylated O-glycan structures, whereas fucosylation is downregulated with differentiation. By performing an integrative approach, we generated hypotheses about the origin of the observed O-glycome changes. These insights pave the way for future endeavors to study the dynamic O-glycosylation patterns in the gut, either produced via cellular biosynthesis or through the action of bacterial glycosidases as well as the functional role of these patterns in homeostasis and dysbiosis at the gut-microbiota interface.
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Affiliation(s)
- K Madunić
- Center for Proteomics and Metabolomics, Leiden University, The Netherlands
| | - Y M C A Luijkx
- Department Chemical Biology and Drug Discovery, Utrecht Institute for Pharmaceutical Sciences and Bijvoet Center for Biomolecular Research, Utrecht University, Utrecht, The Netherlands; Department Biomolecular Health Sciences, Utrecht University, Utrecht, The Netherlands
| | - O A Mayboroda
- Center for Proteomics and Metabolomics, Leiden University, The Netherlands
| | - G M C Janssen
- Center for Proteomics and Metabolomics, Leiden University, The Netherlands
| | - P A van Veelen
- Center for Proteomics and Metabolomics, Leiden University, The Netherlands
| | - K Strijbis
- Department Biomolecular Health Sciences, Utrecht University, Utrecht, The Netherlands
| | - T Wennekes
- Department Chemical Biology and Drug Discovery, Utrecht Institute for Pharmaceutical Sciences and Bijvoet Center for Biomolecular Research, Utrecht University, Utrecht, The Netherlands
| | | | - M Wuhrer
- Center for Proteomics and Metabolomics, Leiden University, The Netherlands.
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7
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van Teijlingen NH, Helgers LC, Sarrami-Forooshani R, Zijlstra-Willems EM, van Hamme JL, Segui-Perez C, van Smoorenburg MY, Borgdorff H, van de Wijgert JH, van Leeuwen E, van der Post JA, Strijbis K, Ribeiro CM, Geijtenbeek TB. Vaginal bacterium Prevotella timonensis turns protective Langerhans cells into HIV-1 reservoirs for virus dissemination. EMBO J 2022; 41:e110629. [PMID: 35968812 PMCID: PMC9531304 DOI: 10.15252/embj.2022110629] [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] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2022] [Revised: 07/08/2022] [Accepted: 07/18/2022] [Indexed: 11/09/2022] Open
Abstract
Dysbiosis of vaginal microbiota is associated with increased HIV-1 acquisition, but the underlying cellular mechanisms remain unclear. Vaginal Langerhans cells (LCs) protect against mucosal HIV-1 infection via autophagy-mediated degradation of HIV-1. As LCs are in continuous contact with bacterial members of the vaginal microbiome, we investigated the impact of commensal and dysbiosis-associated vaginal (an)aerobic bacterial species on the antiviral function of LCs. Most of the tested bacteria did not affect the HIV-1 restrictive function of LCs. However, Prevotella timonensis induced a vast uptake of HIV-1 by vaginal LCs. Internalized virus remained infectious for days and uptake was unaffected by antiretroviral drugs. P. timonensis-exposed LCs efficiently transmitted HIV-1 to target cells both in vitro and ex vivo. Additionally, P. timonensis exposure enhanced uptake and transmission of the HIV-1 variants that establish infection after sexual transmission, the so-called Transmitted Founder variants. Our findings, therefore, suggest that P. timonensis might set the stage for enhanced HIV-1 susceptibility during vaginal dysbiosis and advocate targeted treatment of P. timonensis during bacterial vaginosis to limit HIV-1 infection.
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Affiliation(s)
- Nienke H van Teijlingen
- Department of Experimental Immunology, Amsterdam UMC Location University of Amsterdam, Amsterdam, The Netherlands.,Amsterdam institute for Infection and Immunity, Amsterdam, The Netherlands
| | - Leanne C Helgers
- Department of Experimental Immunology, Amsterdam UMC Location University of Amsterdam, Amsterdam, The Netherlands.,Amsterdam institute for Infection and Immunity, Amsterdam, The Netherlands
| | - Ramin Sarrami-Forooshani
- Department of Experimental Immunology, Amsterdam UMC Location University of Amsterdam, Amsterdam, The Netherlands.,ATMP Department, Breast Cancer Research Center, Motamed Cancer Institute, ACECR, Tehran, Iran
| | - Esther M Zijlstra-Willems
- Department of Experimental Immunology, Amsterdam UMC Location University of Amsterdam, Amsterdam, The Netherlands.,Amsterdam institute for Infection and Immunity, Amsterdam, The Netherlands
| | - John L van Hamme
- Department of Experimental Immunology, Amsterdam UMC Location University of Amsterdam, Amsterdam, The Netherlands.,Amsterdam institute for Infection and Immunity, Amsterdam, The Netherlands
| | - Celia Segui-Perez
- Division Infectious Diseases and Immunology, Department of Biomolecular Health Sciences, Faculty of Veterinary Medicine, University of Utrecht, Utrecht, The Netherlands
| | - Marleen Y van Smoorenburg
- Department of Experimental Immunology, Amsterdam UMC Location University of Amsterdam, Amsterdam, The Netherlands.,Amsterdam institute for Infection and Immunity, Amsterdam, The Netherlands
| | - Hanneke Borgdorff
- Amsterdam Institute for Global Health and Development (AIGHD), Amsterdam, The Netherlands
| | - Janneke Hhm van de Wijgert
- Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Elisabeth van Leeuwen
- Department of Obstetrics and Gynecology, Amsterdam UMC Location University of Amsterdam, Amsterdam, The Netherlands
| | - Joris Am van der Post
- Department of Obstetrics and Gynecology, Amsterdam UMC Location University of Amsterdam, Amsterdam, The Netherlands
| | - Karin Strijbis
- Division Infectious Diseases and Immunology, Department of Biomolecular Health Sciences, Faculty of Veterinary Medicine, University of Utrecht, Utrecht, The Netherlands
| | - Carla Ms Ribeiro
- Department of Experimental Immunology, Amsterdam UMC Location University of Amsterdam, Amsterdam, The Netherlands.,Amsterdam institute for Infection and Immunity, Amsterdam, The Netherlands
| | - Teunis Bh Geijtenbeek
- Department of Experimental Immunology, Amsterdam UMC Location University of Amsterdam, Amsterdam, The Netherlands.,Amsterdam institute for Infection and Immunity, Amsterdam, The Netherlands
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8
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Luijkx YMCA, Jongkees S, Strijbis K, Wennekes T. Development of a 1,2-difluorofucoside activity-based probe for profiling GH29 fucosidases. Org Biomol Chem 2021; 19:2968-2977. [PMID: 33729259 DOI: 10.1039/d1ob00054c] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
GH29 α-l-fucosidases catalyze hydrolysis of terminal α-l-fucosyl linkages with varying specificity and are expressed by prominent members of the human gut microbiota. Both homeostasis and dysbiosis at the human intestinal microbiota interface have been correlated with altered fucosidase activity. Herein we describe the development of a 2-deoxy-2-fluoro fucosyl fluoride derivative with an azide mini-tag as an activity-based probe (ABP) for selective in vitro labelling of GH29 α-l-fucosidases. Only catalytically active fucosidases are inactivated by this ABP, allowing their functionalization with a biotin reporter group via the CuAAC reaction and subsequent in-gel detection at nanogram levels. The ABP we present here is shown to be active against a GH29 α-l-fucosidase from Bacteroides fragilis and capable of labeling two other GH29 α-l-fucosidases with different linkage specificity, illustrating its broader utility. This novel ABP is a valuable addition to the toolbox of fucosidase probes by allowing identification and functional studies of the wide variety of GH29 fucosidases, including those in the gut microbiota.
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Affiliation(s)
- Yvette M C A Luijkx
- Department Chemical Biology and Drug Discovery, Utrecht Institute for Pharmaceutical Sciences and Bijvoet Center for Biomolecular Research, Utrecht University, Utrecht, The Netherlands.
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9
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Abstract
Mucus plays a pivotal role in protecting the respiratory tract against microbial infections. It acts as a primary contact site to entrap microbes and facilitates their removal from the respiratory tract via the coordinated beating of motile cilia. The major components of airway mucus are heavily O-glycosylated mucin glycoproteins, divided into gel-forming mucins and transmembrane mucins. The gel-forming mucins MUC5AC and MUC5B are the primary structural components of airway mucus, and they enable efficient clearance of pathogens by mucociliary clearance. MUC5B is constitutively expressed in the healthy airway, whereas MUC5AC is upregulated in response to inflammatory challenge. MUC1, MUC4, and MUC16 are the three major transmembrane mucins of the respiratory tracts which prevent microbial invasion, can act as releasable decoy receptors, and activate intracellular signal transduction pathways. Pathogens have evolved virulence factors such as adhesins that facilitate interaction with specific mucins and mucin glycans, for example, terminal sialic acids. Mucin expression and glycosylation are dependent on the inflammatory state of the respiratory tract and are directly regulated by proinflammatory cytokines and microbial ligands. Gender and age also impact mucin glycosylation and expression through the female sex hormone estradiol and age-related downregulation of mucin production. Here, we discuss what is currently known about the role of respiratory mucins and their glycans during bacterial and viral infections of the airways and their relevance for the novel coronavirus severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Understanding the impact of microbe-mucin interaction in the respiratory tract could inspire the development of novel therapies to boost mucosal defense and combat respiratory infections.
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Affiliation(s)
- Maitrayee Chatterjee
- Department Biomolecular Health Sciences, Division Infectious Diseases and Immunology, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
| | - Jos P M van Putten
- Department Biomolecular Health Sciences, Division Infectious Diseases and Immunology, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
| | - Karin Strijbis
- Department Biomolecular Health Sciences, Division Infectious Diseases and Immunology, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
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10
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Luijkx YMCA, Bleumink NMC, Jiang J, Overkleeft HS, Wösten MMSM, Strijbis K, Wennekes T. Bacteroides fragilis fucosidases facilitate growth and invasion of Campylobacter jejuni in the presence of mucins. Cell Microbiol 2020; 22:e13252. [PMID: 32827216 PMCID: PMC7685106 DOI: 10.1111/cmi.13252] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [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: 04/16/2020] [Revised: 07/23/2020] [Accepted: 07/24/2020] [Indexed: 12/11/2022]
Abstract
The enteropathogenic bacterium, Campylobacter jejuni, was considered to be non‐saccharolytic, but recently it emerged that l‐fucose plays a central role in C. jejuni virulence. Half of C. jejuni clinical isolates possess an operon for l‐fucose utilisation. In the intestinal tract, l‐fucose is abundantly available in mucin O‐linked glycan structures, but C. jejuni lacks a fucosidase enzyme essential to release the l‐fucose. We set out to determine how C. jejuni can gain access to these intestinal l‐fucosides. Growth of the fuc + C. jejuni strains, 129,108 and NCTC 11168, increased in the presence of l‐fucose while fucose permease knockout strains did not benefit from additional l‐fucose. With fucosidase assays and an activity‐based probe, we confirmed that Bacteriodes fragilis, an abundant member of the intestinal microbiota, secretes active fucosidases. In the presence of mucins, C. jejuni was dependent on B. fragilis fucosidase activity for increased growth. Campylobacter jejuni invaded Caco‐2 intestinal cells that express complex O‐linked glycan structures that contain l‐fucose. In infection experiments, C. jejuni was more invasive in the presence of B. fragilis and this increase is due to fucosidase activity. We conclude that C. jejuni fuc + strains are dependent on exogenous fucosidases for increased growth and invasion.
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Affiliation(s)
- Yvette M C A Luijkx
- Department Chemical Biology and Drug Discovery, Utrecht Institute for Pharmaceutical Sciences and Bijvoet Center for Biomolecular Research, Utrecht University, Utrecht, The Netherlands.,Department Biomolecular Health Sciences, Utrecht University, Utrecht, The Netherlands
| | - Nancy M C Bleumink
- Department Biomolecular Health Sciences, Utrecht University, Utrecht, The Netherlands
| | - Jianbing Jiang
- Leiden institute of Chemistry, Leiden University, Leiden, The Netherlands.,Health Science Center, School of Pharmacy, Shenzhen University, Shenzhen, China
| | | | - Marc M S M Wösten
- Department Biomolecular Health Sciences, Utrecht University, Utrecht, The Netherlands
| | - Karin Strijbis
- Department Biomolecular Health Sciences, Utrecht University, Utrecht, The Netherlands
| | - Tom Wennekes
- Department Chemical Biology and Drug Discovery, Utrecht Institute for Pharmaceutical Sciences and Bijvoet Center for Biomolecular Research, Utrecht University, Utrecht, The Netherlands
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11
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Li X, Bleumink-Pluym NMC, Luijkx YMCA, Wubbolts RW, van Putten JPM, Strijbis K. MUC1 is a receptor for the Salmonella SiiE adhesin that enables apical invasion into enterocytes. PLoS Pathog 2019; 15:e1007566. [PMID: 30716138 PMCID: PMC6375660 DOI: 10.1371/journal.ppat.1007566] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2018] [Revised: 02/14/2019] [Accepted: 01/06/2019] [Indexed: 01/08/2023] Open
Abstract
The cellular invasion machinery of the enteric pathogen Salmonella consists of a type III secretion system (T3SS) with injectable virulence factors that induce uptake by macropinocytosis. Salmonella invasion at the apical surface of intestinal epithelial cells is inefficient, presumably because of a glycosylated barrier formed by transmembrane mucins that prevents T3SS contact with host cells. We observed that Salmonella is capable of apical invasion of intestinal epithelial cells that express the transmembrane mucin MUC1. Knockout of MUC1 in HT29-MTX cells or removal of MUC1 sialic acids by neuraminidase treatment reduced Salmonella apical invasion but did not affect lateral invasion that is not hampered by a defensive barrier. A Salmonella deletion strain lacking the SiiE giant adhesin was unable to invade intestinal epithelial cells through MUC1. SiiE-positive Salmonella closely associated with the MUC1 layer at the apical surface, but invaded Salmonella were negative for the adhesin. Our findings uncover that the transmembrane mucin MUC1 is required for Salmonella SiiE-mediated entry of enterocytes via the apical route. The bacterial pathogen Salmonella enterica is one of the most common causes of human foodborne infection affecting millions of people worldwide each year. To establish infection, Salmonella needs to cross the mucus layer and invade intestinal epithelial cells from the apical surface. However, the apical surface of intestinal epithelial cells is covered with a defensive barrier of large glycosylated transmembrane mucins. These large proteins prevent contact between the Salmonella type III secretion needle and the host plasma membrane thereby preventing invasion. We show for the first time that MUC1, one of the intestinal apical transmembrane mucins, facilitates Salmonella invasion. The Salmonella giant adhesin SiiE is the adhesin responsible for engaging MUC1 and the interaction is mediated by glycans on MUC1. We propose that SiiE interacts with MUC1 in a zipper-like manner that involves repetitive domains in both proteins. Adhesin-receptor interactions are essential for bacterial infection of host cells and key factors in determining target tissues and host range of bacteria. The SiiE-MUC1 invasion pathway may explain tropism of different Salmonella strains and provide a novel target for infection intervention and prevention.
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Affiliation(s)
- Xinyue Li
- Department of Infectious Diseases & Immunology, Utrecht University, Utrecht, The Netherlands
| | | | - Yvette M. C. A. Luijkx
- Department of Infectious Diseases & Immunology, Utrecht University, Utrecht, The Netherlands
- Department of Chemical Biology and Drug Discovery, Utrecht Institute for Pharmaceutical Sciences and Bijvoet Center for Biomolecular Research, Utrecht University, Utrecht, The Netherlands
| | - Richard W. Wubbolts
- Department of Biochemistry and Cell Biology, Utrecht University, Utrecht, The Netherlands
| | - Jos P. M. van Putten
- Department of Infectious Diseases & Immunology, Utrecht University, Utrecht, The Netherlands
| | - Karin Strijbis
- Department of Infectious Diseases & Immunology, Utrecht University, Utrecht, The Netherlands
- * E-mail:
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Freitag CM, Strijbis K, van Putten JPM. Host cell binding of the flagellar tip protein of Campylobacter jejuni. Cell Microbiol 2017; 19. [PMID: 28008697 DOI: 10.1111/cmi.12714] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2016] [Accepted: 12/16/2016] [Indexed: 12/29/2022]
Abstract
Flagella are nanofibers that drive bacterial movement. The filaments are generally composed of thousands of tightly packed flagellin subunits with a terminal cap protein, named FliD. Here, we report that the FliD protein of the bacterial pathogen Campylobacter jejuni binds to host cells. Live-cell imaging and confocal microscopy showed initial contact of the bacteria with epithelial cells via the flagella tip. Recombinant FliD protein bound to the surface of intestinal epithelial cells in a dose-dependent fashion. Search for the FliD binding site on the host cell using cells with defined glycosylation defects indicated glycosaminoglycans as a putative target. Heparinase treatment of wild type cells and an excess of soluble heparin abolished FliD binding. Binding assays showed direct and specific binding of FliD to heparin. Addition of an excess of purified FliD or heparin reduced the attachment of viable C. jejuni to the host cells. The host cell binding domain of FliD was mapped to the central region of the protein. Overall, our results indicate that the C. jejuni flagellar tip protein FliD acts as an attachment factor that interacts with cell surface heparan sulfate glycosaminoglycan receptors.
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Affiliation(s)
- Claudia M Freitag
- Department of Infectious Diseases and Immunology, Utrecht University, Utrecht, The Netherlands
| | - Karin Strijbis
- Department of Infectious Diseases and Immunology, Utrecht University, Utrecht, The Netherlands
| | - Jos P M van Putten
- Department of Infectious Diseases and Immunology, Utrecht University, Utrecht, The Netherlands
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van Putten JPM, Strijbis K. Transmembrane Mucins: Signaling Receptors at the Intersection of Inflammation and Cancer. J Innate Immun 2017; 9:281-299. [PMID: 28052300 DOI: 10.1159/000453594] [Citation(s) in RCA: 165] [Impact Index Per Article: 23.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2016] [Accepted: 11/19/2016] [Indexed: 12/18/2022] Open
Abstract
Mucosal surfaces line our body cavities and provide the interaction surface between commensal and pathogenic microbiota and the host. The barrier function of the mucosal layer is largely maintained by gel-forming mucin proteins that are secreted by goblet cells. In addition, mucosal epithelial cells express cell-bound mucins that have both barrier and signaling functions. The family of transmembrane mucins consists of diverse members that share a few characteristics. The highly glycosylated extracellular mucin domains inhibit invasion by pathogenic bacteria and can form a tight mesh structure that protects cells in harmful conditions. The intracellular tails of transmembrane mucins can be phosphorylated and connect to signaling pathways that regulate inflammation, cell-cell interactions, differentiation, and apoptosis. Transmembrane mucins play important roles in preventing infection at mucosal surfaces, but are also renowned for their contributions to the development, progression, and metastasis of adenocarcinomas. In general, transmembrane mucins seem to have evolved to monitor and repair damaged epithelia, but these functions can be highjacked by cancer cells to yield a survival advantage. This review presents an overview of the current knowledge of the functions of transmembrane mucins in inflammatory processes and carcinogenesis in order to better understand the diverse functions of these multifunctional proteins.
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Affiliation(s)
- Jos P M van Putten
- Department of Infectious Diseases and Immunology, Utrecht University, Utrecht, The Netherlands
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14
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Haapasalo-Tuomainen K, Wollman A, de Haas C, Aerts P, Veld EV, Strijbis K, Wubbolts R, van Kessel K, Leake M, van Strijp J. Characterization of the stoichiometry of the complex formed by Staphylococcal toxin LukSF and human C5a receptor. Immunobiology 2016. [DOI: 10.1016/j.imbio.2016.06.039] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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15
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Lin MY, de Zoete MR, van Putten JPM, Strijbis K. Redirection of Epithelial Immune Responses by Short-Chain Fatty Acids through Inhibition of Histone Deacetylases. Front Immunol 2015; 6:554. [PMID: 26579129 PMCID: PMC4630660 DOI: 10.3389/fimmu.2015.00554] [Citation(s) in RCA: 91] [Impact Index Per Article: 10.1] [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: 07/10/2015] [Accepted: 10/16/2015] [Indexed: 01/17/2023] Open
Abstract
Short-chain fatty acids (SCFAs) are products of microbial fermentation that are important for intestinal epithelial health. Here, we describe that SCFAs have rapid and reversible effects on toll-like receptor (TLR) responses in epithelial cells. Incubation of HEK293 or HeLa epithelial cells with the SCFAs butyrate or propionate at physiological concentrations enhanced NF-κB activation induced by TLR5, TLR2/1, TLR4, and TLR9 agonists. NF-κB activation in response to tumor necrosis factor α (TNFα) was also increased by SCFAs. Comparative transcript analysis of HT-29 colon epithelial cells revealed that SCFAs enhanced TLR5-induced transcription of TNFα but dampened or even abolished the TLR5-mediated induction of IL-8 and monocyte chemotactic protein 1. SCFAs are known inhibitors of histone deacetylases (HDACs). Butyrate or propionate caused a rapid increase in histone acetylation in epithelial cells, similar to the small molecule HDAC inhibitor trichostatin A (TSA). TSA also mimicked the effects of SCFAs on TLR–NF-κB responses. This study shows that bacterial SCFAs rapidly alter the epigenetic state of host cells resulting in redirection of the innate immune response and selective reprograming of cytokine/chemokine expression.
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Affiliation(s)
- May Young Lin
- Department of Infectious Diseases and Immunology, Utrecht University , Utrecht , Netherlands
| | - Marcel R de Zoete
- Department of Infectious Diseases and Immunology, Utrecht University , Utrecht , Netherlands
| | - Jos P M van Putten
- Department of Infectious Diseases and Immunology, Utrecht University , Utrecht , Netherlands
| | - Karin Strijbis
- Department of Infectious Diseases and Immunology, Utrecht University , Utrecht , Netherlands
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16
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Tafesse FG, Rashidfarrokhi A, Schmidt FI, Freinkman E, Dougan S, Dougan M, Esteban A, Maruyama T, Strijbis K, Ploegh HL. Disruption of Sphingolipid Biosynthesis Blocks Phagocytosis of Candida albicans. PLoS Pathog 2015; 11:e1005188. [PMID: 26431038 PMCID: PMC4592247 DOI: 10.1371/journal.ppat.1005188] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2015] [Accepted: 09/03/2015] [Indexed: 01/08/2023] Open
Abstract
The ability of phagocytes to clear pathogens is an essential attribute of the innate immune response. The role of signaling lipid molecules such as phosphoinositides is well established, but the role of membrane sphingolipids in phagocytosis is largely unknown. Using a genetic approach and small molecule inhibitors, we show that phagocytosis of Candida albicans requires an intact sphingolipid biosynthetic pathway. Blockade of serine-palmitoyltransferase (SPT) and ceramide synthase-enzymes involved in sphingolipid biosynthesis- by myriocin and fumonisin B1, respectively, impaired phagocytosis by phagocytes. We used CRISPR/Cas9-mediated genome editing to generate Sptlc2-deficient DC2.4 dendritic cells, which lack serine palmitoyl transferase activity. Sptlc2-/- DC2.4 cells exhibited a stark defect in phagocytosis, were unable to bind fungal particles and failed to form a normal phagocytic cup to engulf C. albicans. Supplementing the growth media with GM1, the major ganglioside present at the cell surface, restored phagocytic activity of Sptlc2-/- DC2.4 cells. While overall membrane trafficking and endocytic pathways remained functional, Sptlc2-/- DC2.4 cells express reduced levels of the pattern recognition receptors Dectin-1 and TLR2 at the cell surface. Consistent with the in vitro data, compromised sphingolipid biosynthesis in mice sensitizes the animal to C. albicans infection. Sphingolipid biosynthesis is therefore critical for phagocytosis and in vivo clearance of C. albicans. The fungus Candida albicans is not only a commensal of the digestive system, but also a common cause of human opportunistic infections. Macrophages and dendritic cells can eliminate C. albicans by phagocytosis, a complex process that involves extensive membrane reorganization at the cell surface. The extent to which membrane lipids, including sphingolipids, contribute to the proper execution of phagocytosis remains largely unknown. Pharmacological blockade of sphingolipid biosynthesis by the small molecule inhibitors myriocin and fumonisin B1 impairs phagocytosis of C. albicans. DC2.4 dendritic cells genetically deficient in Sptlc2, the enzyme that catalyzes the first and rate-limiting step in the sphingolipid biosynthetic pathway, are likewise defective in phagocytosis of C. albicans. Sptlc2-/- DC2.4 cells showed reduced binding of C. albicans, but overall membrane transport and protein secretion remained functional. Sptlc2-deficient cells express reduced levels of the receptors Dectin-1 and TLR2 at the cell surface, and are unable to form a normal phagocytic cup. Exogenous addition of the major ganglioside GM1 restored phagocytic ability of Sptlc2-/- DC2.4 cells. Mice with compromised sphingolipid production upon in vivo treatment with fumonisin B1 fail to eradicate C. albicans, consistent with the in vitro results. Sphingolipids are thus essential for clearance of fungal infection through phagocytosis, and hence indispensable for the proper functioning of the innate immune system.
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Affiliation(s)
- Fikadu G. Tafesse
- Whitehead Institute for Biomedical Research and Massachusetts Institute of Technology, Cambridge, Massachusetts, United States of America
- Ragon Institute of MGH, MIT and Harvard, Cambridge, Massachusetts, United States of America
- * E-mail: ,
| | - Ali Rashidfarrokhi
- Whitehead Institute for Biomedical Research and Massachusetts Institute of Technology, Cambridge, Massachusetts, United States of America
- Ragon Institute of MGH, MIT and Harvard, Cambridge, Massachusetts, United States of America
| | - Florian I. Schmidt
- Whitehead Institute for Biomedical Research and Massachusetts Institute of Technology, Cambridge, Massachusetts, United States of America
| | - Elizaveta Freinkman
- Whitehead Institute for Biomedical Research and Massachusetts Institute of Technology, Cambridge, Massachusetts, United States of America
| | - Stephanie Dougan
- Whitehead Institute for Biomedical Research and Massachusetts Institute of Technology, Cambridge, Massachusetts, United States of America
| | - Michael Dougan
- Whitehead Institute for Biomedical Research and Massachusetts Institute of Technology, Cambridge, Massachusetts, United States of America
| | - Alexandre Esteban
- Whitehead Institute for Biomedical Research and Massachusetts Institute of Technology, Cambridge, Massachusetts, United States of America
| | - Takeshi Maruyama
- Whitehead Institute for Biomedical Research and Massachusetts Institute of Technology, Cambridge, Massachusetts, United States of America
| | - Karin Strijbis
- Whitehead Institute for Biomedical Research and Massachusetts Institute of Technology, Cambridge, Massachusetts, United States of America
| | - Hidde L. Ploegh
- Whitehead Institute for Biomedical Research and Massachusetts Institute of Technology, Cambridge, Massachusetts, United States of America
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Tillmann AT, Strijbis K, Cameron G, Radmaneshfar E, Thiel M, Munro CA, MacCallum DM, Distel B, Gow NAR, Brown AJP. Contribution of Fdh3 and Glr1 to Glutathione Redox State, Stress Adaptation and Virulence in Candida albicans. PLoS One 2015; 10:e0126940. [PMID: 26039593 PMCID: PMC4454436 DOI: 10.1371/journal.pone.0126940] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2015] [Accepted: 04/09/2015] [Indexed: 01/04/2023] Open
Abstract
The major fungal pathogen of humans, Candida albicans, is exposed to reactive nitrogen and oxygen species following phagocytosis by host immune cells. In response to these toxins, this fungus activates potent anti-stress responses that include scavenging of reactive nitrosative and oxidative species via the glutathione system. Here we examine the differential roles of two glutathione recycling enzymes in redox homeostasis, stress adaptation and virulence in C. albicans: glutathione reductase (Glr1) and the S-nitrosoglutathione reductase (GSNOR), Fdh3. We show that the NADPH-dependent Glr1 recycles GSSG to GSH, is induced in response to oxidative stress and is required for resistance to macrophage killing. GLR1 deletion increases the sensitivity of C. albicans cells to H2O2, but not to formaldehyde or NO. In contrast, Fdh3 detoxifies GSNO to GSSG and NH3, and FDH3 inactivation delays NO adaptation and increases NO sensitivity. C. albicans fdh3⎔ cells are also sensitive to formaldehyde, suggesting that Fdh3 also contributes to formaldehyde detoxification. FDH3 is induced in response to nitrosative, oxidative and formaldehyde stress, and fdh3Δ cells are more sensitive to killing by macrophages. Both Glr1 and Fdh3 contribute to virulence in the Galleria mellonella and mouse models of systemic infection. We conclude that Glr1 and Fdh3 play differential roles during the adaptation of C. albicans cells to oxidative, nitrosative and formaldehyde stress, and hence during the colonisation of the host. Our findings emphasise the importance of the glutathione system and the maintenance of intracellular redox homeostasis in this major pathogen.
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Affiliation(s)
- Anna T Tillmann
- Aberdeen Fungal Group, School of Medical Sciences, Institute of Medical Sciences, University of Aberdeen, Aberdeen, United Kingdom
| | - Karin Strijbis
- Department of Medical Biochemistry, Academic Medical Center, University of Amsterdam, Amsterdam, Netherlands
| | - Gary Cameron
- Division of Applied Medicine, Mass Spectrometry Section, University of Aberdeen, Aberdeen, United Kingdom
| | - Elahe Radmaneshfar
- Institute for Complex Systems and Mathematical Biology, SUPA, University of Aberdeen, Aberdeen, United Kingdom
| | - Marco Thiel
- Institute for Complex Systems and Mathematical Biology, SUPA, University of Aberdeen, Aberdeen, United Kingdom
| | - Carol A Munro
- Aberdeen Fungal Group, School of Medical Sciences, Institute of Medical Sciences, University of Aberdeen, Aberdeen, United Kingdom
| | - Donna M MacCallum
- Aberdeen Fungal Group, School of Medical Sciences, Institute of Medical Sciences, University of Aberdeen, Aberdeen, United Kingdom
| | - Ben Distel
- Department of Medical Biochemistry, Academic Medical Center, University of Amsterdam, Amsterdam, Netherlands
| | - Neil A R Gow
- Aberdeen Fungal Group, School of Medical Sciences, Institute of Medical Sciences, University of Aberdeen, Aberdeen, United Kingdom
| | - Alistair J P Brown
- Aberdeen Fungal Group, School of Medical Sciences, Institute of Medical Sciences, University of Aberdeen, Aberdeen, United Kingdom
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Strijbis K, Yilmaz ÖH, Dougan SK, Esteban A, Gröne A, Kumamoto CA, Ploegh HL. Intestinal colonization by Candida albicans alters inflammatory responses in Bruton's tyrosine kinase-deficient mice. PLoS One 2014; 9:e112472. [PMID: 25379804 PMCID: PMC4224491 DOI: 10.1371/journal.pone.0112472] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2014] [Accepted: 10/15/2014] [Indexed: 01/01/2023] Open
Abstract
The commensal yeast Candida albicans is part of the human intestinal microflora and is considered a "pathobiont", a resident microbe with pathogenic potential yet harmless under normal conditions. The aim of this study was to investigate the effect of C. albicans on inflammation of the intestinal tract and the role of Bruton's tyrosine kinase (Btk). Btk is an enzyme that modulates downstream signaling of multiple receptors involved in innate and adaptive immunity, including the major anti-fungal receptor Dectin-1. Colitis was induced in wild type and Btk-/- mice by treatment with dextran sodium sulfate (DSS) and the gastrointestinal tract of selected treatment groups were then colonized with C. albicans. Colonization by C. albicans neither dampened nor exacerbated inflammation in wild type mice, but colon length and spleen weight were improved in Btk-deficient mice colonized with C. albicans. Neutrophil infiltration was comparable between wild type and Btk-/- mice, but the knockout mice displayed severely reduced numbers of macrophages in the colon during both DSS and DSS/Candida treatment. Smaller numbers and reduced responsiveness of Btk-/- macrophages might partially explain the improved colon length of Btk-/- mice as a result of Candida colonization. Surprisingly, DSS/Candida-treated Btk-/- animals had higher levels of certain pro-inflammatory cytokines and levels of the anti-inflammatory cytokine TGF-β were reduced compared to wild type. A clustering and correlation analysis showed that for wild type animals, spleen TGF-β and colon IL-10 and for Btk-/- spleen and colon levels of IL-17A best correlated with the inflammatory parameters. We conclude that in Btk-/- immunocompromised animals, colonization of the gastrointestinal tract by the commensal yeast C. albicans alters inflammatory symptoms associated with colitis.
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Affiliation(s)
- Karin Strijbis
- Whitehead Institute for Biomedical Research, Cambridge, Massachusetts, United States of America
- * E-mail:
| | - Ömer H. Yilmaz
- Whitehead Institute for Biomedical Research, Cambridge, Massachusetts, United States of America
| | - Stephanie K. Dougan
- Whitehead Institute for Biomedical Research, Cambridge, Massachusetts, United States of America
| | - Alexandre Esteban
- Whitehead Institute for Biomedical Research, Cambridge, Massachusetts, United States of America
| | - Andrea Gröne
- Department of Pathobiology, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
| | - Carol A. Kumamoto
- Department of Molecular Biology and Microbiology, School of Medicine, Tufts University, Boston, Massachusetts, United States of America
| | - Hidde L. Ploegh
- Whitehead Institute for Biomedical Research, Cambridge, Massachusetts, United States of America
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Tafesse F, Strijbis K, Ploegh H. Quantitative Analysis of Cellular Diacylglycerol Content. Bio Protoc 2014; 4:e1202. [DOI: 10.21769/bioprotoc.1202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022] Open
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Abstract
Circular proteins occur naturally and have been found in microorganisms, plants, and eukaryotes where they are commonly involved in host defense. Properties of circular proteins include enhanced resistance to exoproteases, increased thermostability, longer life spans, and increased activity. Using an enzymatic approach based on the bacterial sortase A (SrtA) transpeptidase, N- and C-termini of conventional linear proteins can be linked resulting in a circular protein. Circularization of bioengineered linear substrate proteins can indeed confer the desirable properties associated with circular proteins. Here, we describe how cells can be manipulated to secrete circularized proteins for substrates of choice via sortase-mediated circularization in the lumen of the endoplasmic reticulum.
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Affiliation(s)
| | - Hidde Ploegh
- Corresponding author: Hiddle Ploegh, Whitehead Institute for Biomedical Research, 9 Cambridge Center, Cambridge, MA, 02142, USA. Tel.:617-324-2031,
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Reales-Calderón JA, Sylvester M, Strijbis K, Jensen ON, Nombela C, Molero G, Gil C. Candida albicans induces pro-inflammatory and anti-apoptotic signals in macrophages as revealed by quantitative proteomics and phosphoproteomics. J Proteomics 2013; 91:106-35. [DOI: 10.1016/j.jprot.2013.06.026] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2013] [Accepted: 06/16/2013] [Indexed: 12/11/2022]
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Strijbis K, Tafesse FG, Fairn GD, Witte MD, Dougan SK, Watson N, Spooner E, Esteban A, Vyas VK, Fink GR, Grinstein S, Ploegh HL. Bruton's Tyrosine Kinase (BTK) and Vav1 contribute to Dectin1-dependent phagocytosis of Candida albicans in macrophages. PLoS Pathog 2013; 9:e1003446. [PMID: 23825946 PMCID: PMC3694848 DOI: 10.1371/journal.ppat.1003446] [Citation(s) in RCA: 71] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2013] [Accepted: 05/07/2013] [Indexed: 12/28/2022] Open
Abstract
Phagocytosis of the opportunistic fungal pathogen Candida albicans by cells of the innate immune system is vital to prevent infection. Dectin-1 is the major phagocytic receptor involved in anti-fungal immunity. We identify two new interacting proteins of Dectin-1 in macrophages, Bruton's Tyrosine Kinase (BTK) and Vav1. BTK and Vav1 are recruited to phagocytic cups containing C. albicans yeasts or hyphae but are absent from mature phagosomes. BTK and Vav1 localize to cuff regions surrounding the hyphae, while Dectin-1 lines the full length of the phagosome. BTK and Vav1 colocalize with the lipid PI(3,4,5)P3 and F-actin at the phagocytic cup, but not with diacylglycerol (DAG) which marks more mature phagosomal membranes. Using a selective BTK inhibitor, we show that BTK contributes to DAG synthesis at the phagocytic cup and the subsequent recruitment of PKCε. BTK- or Vav1-deficient peritoneal macrophages display a defect in both zymosan and C. albicans phagocytosis. Bone marrow-derived macrophages that lack BTK or Vav1 show reduced uptake of C. albicans, comparable to Dectin1-deficient cells. BTK- or Vav1-deficient mice are more susceptible to systemic C. albicans infection than wild type mice. This work identifies an important role for BTK and Vav1 in immune responses against C. albicans.
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Affiliation(s)
- Karin Strijbis
- Whitehead Institute for Biomedical Research, Cambridge, Massachusetts, United States of America
| | - Fikadu G. Tafesse
- Whitehead Institute for Biomedical Research, Cambridge, Massachusetts, United States of America
| | - Gregory D. Fairn
- Keenan Research Centre of the Li Ka Shing Knowledge Institute, St. Michael's Hospital, Department of Surgery, University of Toronto, Toronto, Ontario, Canada
| | - Martin D. Witte
- Whitehead Institute for Biomedical Research, Cambridge, Massachusetts, United States of America
| | - Stephanie K. Dougan
- Whitehead Institute for Biomedical Research, Cambridge, Massachusetts, United States of America
| | - Nicki Watson
- Whitehead Institute for Biomedical Research, Cambridge, Massachusetts, United States of America
| | - Eric Spooner
- Whitehead Institute for Biomedical Research, Cambridge, Massachusetts, United States of America
| | - Alexandre Esteban
- Whitehead Institute for Biomedical Research, Cambridge, Massachusetts, United States of America
| | - Valmik K. Vyas
- Whitehead Institute for Biomedical Research, Cambridge, Massachusetts, United States of America
| | - Gerald R. Fink
- Whitehead Institute for Biomedical Research, Cambridge, Massachusetts, United States of America
| | - Sergio Grinstein
- Keenan Research Centre of the Li Ka Shing Knowledge Institute, St. Michael's Hospital, Department of Surgery, University of Toronto, Toronto, Ontario, Canada
- Program in Cell Biology, Hospital for Sick Children, Toronto, Ontario, Canada
| | - Hidde L. Ploegh
- Whitehead Institute for Biomedical Research, Cambridge, Massachusetts, United States of America
- * E-mail:
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Abstract
Sortagging is a versatile method for site-specific modification of proteins as applied to a variety of in vitro reactions. Here, we explore possibilities of adapting the sortase method for use in living cells. For intracellular sortagging, we employ the Ca²⁺-independent sortase A transpeptidase (SrtA) from Streptococcus pyogenes. Substrate proteins were equipped with the C-terminal sortase-recognition motif (LPXTG); we used proteins with an N-terminal (oligo)glycine as nucleophiles. We show that sortase-dependent protein ligation can be achieved in Saccharomyces cerevisiae and in mammalian HEK293T cells, both in the cytosol and in the lumen of the endoplasmic reticulum (ER). ER luminal sortagging enables secretion of the reaction products, among which circular polypeptides. Protein ligation of substrate and nucleophile occurs within 30 min of translation. The versatility of the method is shown by protein ligation of multiple substrates with green fluorescent protein-based nucleophiles in different intracellular compartments.
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Affiliation(s)
- Karin Strijbis
- Whitehead Institute for Biomedical Research, 9 Cambridge Center, Cambridge, MA 02142, USA
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Strijbis K, van den Burg J, Visser WF, van den Berg M, Distel B. Alternative splicing directs dual localization of Candida albicans 6-phosphogluconate dehydrogenase to cytosol and peroxisomes. FEMS Yeast Res 2011; 12:61-8. [PMID: 22094058 DOI: 10.1111/j.1567-1364.2011.00761.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2011] [Accepted: 11/05/2011] [Indexed: 11/28/2022] Open
Abstract
The pentose phosphate pathway (PPP) is the main source of NADPH in the cell and therefore essential for the maintenance of the redox balance and anabolic reactions. NADPH is produced by the two dehydrogenases in the oxidative branch of the PPP: glucose-6-phosphate dehydrogenase (Zwf1) and 6-phosphogluconate dehydrogenase (Gnd1). We observed that in the commensal fungus Candida albicans these two enzymes contain putative peroxisomal targeting signals (PTSs): Zwf1 has a putative PTS1, while the annotated intron of GND1 encodes a PTS2. By subcellular fractionation and fluorescence microscopy, we show that both enzymes have a dual localization in which the majority is cytosolic, but a small fraction is peroxisome associated. Analysis of GND1 transcripts revealed that dual targeting of Gnd1 is directed by alternative splicing resulting in two Gnd1 isoforms, one without targeting signals localized to the cytosol and one with an N-terminal PTS2 targeted to peroxisomes. To our knowledge, Gnd1 is the first example of dual targeting of a protein by alternative splicing in C. albicans. In silico analysis suggests that PTS-mediated peroxisomal targeting of Zwf1 and Gnd1 is conserved across closely related Candida species. We discuss putative functions of the peroxisomal oxidative PPP in these organisms.
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Affiliation(s)
- Karin Strijbis
- Department of Medical Biochemistry, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
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25
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McGehee AM, Strijbis K, Guillen E, Eng T, Kirak O, Ploegh HL. Ubiquitin-dependent control of class II MHC localization is dispensable for antigen presentation and antibody production. PLoS One 2011; 6:e18817. [PMID: 21533087 PMCID: PMC3080378 DOI: 10.1371/journal.pone.0018817] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2010] [Accepted: 03/10/2011] [Indexed: 11/21/2022] Open
Abstract
Controlled localization of class II MHC molecules is essential for proper class II MHC-restricted antigen presentation and the subsequent initiation of an adaptive immune response. Ubiquitination of class II MHC molecules on cytosolic lysine (K225) of the β-chain has been shown to affect localization of the complex. We generated mice in which the endogenous β-chain locus is replaced with a GFP tagged mutant version that lacks the cytosolic lysine residue (I-A-β-K225R-EGFP). These mice have elevated levels of class II MHC as compared to I-A-β-EGFP mice, and immature bone marrow-derived dendritic cells show redistribution of class II MHC to the cell surface. Nonetheless, in these same cells efficiency of antigen presentation is unaffected in I-A-β-K225R-EGFP mice, as assayed for presentation of ovalbumin to appropriately specific T cells. The I-A-β-K225R-EGFP animals have normal CD4 T cell populations and are capable of generating antigen-specific antibody in response to model antigens and viral infection. We therefore conclude that in our experimental system modulation of trafficking by ubiquitination of residue K225 of the β-chain is not essential for the function of class II MHC products in antigen presentation or antibody production.
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Affiliation(s)
- Annette M. McGehee
- Whitehead Institute for Biomedical Research, Cambridge, Massachusetts, United States of America
| | - Karin Strijbis
- Whitehead Institute for Biomedical Research, Cambridge, Massachusetts, United States of America
| | - Eduardo Guillen
- Whitehead Institute for Biomedical Research, Cambridge, Massachusetts, United States of America
| | - Thomas Eng
- Whitehead Institute for Biomedical Research, Cambridge, Massachusetts, United States of America
| | - Oktay Kirak
- Whitehead Institute for Biomedical Research, Cambridge, Massachusetts, United States of America
| | - Hidde L. Ploegh
- Whitehead Institute for Biomedical Research, Cambridge, Massachusetts, United States of America
- * E-mail:
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Strijbis K, van Roermund CW, van den Burg J, van den Berg M, Hardy GPM, Wanders RJ, Distel B. Contributions of carnitine acetyltransferases to intracellular acetyl unit transport in Candida albicans. J Biol Chem 2010; 285:24335-46. [PMID: 20522553 DOI: 10.1074/jbc.m109.094250] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Transport of acetyl-CoA between intracellular compartments is mediated by carnitine acetyltransferases (Cats) that reversibly link acetyl units to the carrier molecule carnitine. The genome of the opportunistic pathogenic yeast Candida albicans encodes several (putative) Cats: the peroxisomal and mitochondrial Cat2 isoenzymes encoded by a single gene and the carnitine acetyltransferase homologs Yat1 and Yat2. To determine the contributions of the individual Cats, various carnitine acetyltransferase mutant strains were constructed and subjected to phenotypic and biochemical analyses on different carbon sources. We show that mitochondrial Cat2 is required for the intramitochondrial conversion of acetylcarnitine to acetyl-CoA, which is essential for a functional tricarboxylic acid cycle during growth on oleate, acetate, ethanol, and citrate. Yat1 is cytosolic and contributes to acetyl-CoA transport from the cytosol during growth on ethanol or acetate, but its activity is not required for growth on oleate. Yat2 is also cytosolic, but we were unable to attribute any function to this enzyme. Surprisingly, peroxisomal Cat2 is essential neither for export of acetyl units during growth on oleate nor for the import of acetyl units during growth on acetate or ethanol. Oxidation of fatty acids still takes place in the absence of peroxisomal Cat2, but biomass formation is absent, and the strain displays a growth delay on acetate and ethanol that can be partially rescued by the addition of carnitine. Based on our results, we present a model for the intracellular flow of acetyl units under various growth conditions and the roles of each of the Cats in this process.
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Affiliation(s)
- Karin Strijbis
- Department of Medical Biochemistry, Academic Medical Center, Meibergdreef 15, 1105 AZ Amsterdam, The Netherlands
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Abstract
The water-soluble zwitterion carnitine is an essential metabolite in eukaryotes required for fatty acid oxidation as it functions as a carrier during transfer of activated acyl and acetyl groups across intracellular membranes. Most eukaryotes are able to synthesize carnitine endogenously, besides their capacity to take up carnitine from the diet or extracellular medium through plasma membrane transporters. This review discusses the current knowledge on carnitine homeostasis with special emphasis on the enzymology of the four steps of the carnitine biosynthesis pathway.
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Affiliation(s)
- Karin Strijbis
- Department of Medical Biochemistry, Academic Medical Center, Amsterdam, The Netherlands
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Strijbis K, Van Roermund CWT, Hardy GP, Van den Burg J, Bloem K, Haan J, Van Vlies N, Wanders RJA, Vaz FM, Distel B. Identification and characterization of a complete carnitine biosynthesis pathway in
Candida albicans. FASEB J 2009; 23:2349-59. [DOI: 10.1096/fj.08-127985] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Karin Strijbis
- Department of Medical BiochemistryAcademic Medical CenterUniversity of AmsterdamAmsterdamThe Netherlands
| | - Carlo W. T. Van Roermund
- Department of Genetic Metabolic DiseasesAcademic Medical CenterUniversity of AmsterdamAmsterdamThe Netherlands
| | - Guy P. Hardy
- Department of Medical BiochemistryAcademic Medical CenterUniversity of AmsterdamAmsterdamThe Netherlands
| | - Janny Van den Burg
- Department of Medical BiochemistryAcademic Medical CenterUniversity of AmsterdamAmsterdamThe Netherlands
| | - Karien Bloem
- Department of Medical BiochemistryAcademic Medical CenterUniversity of AmsterdamAmsterdamThe Netherlands
| | - Jolanda Haan
- Department of Medical BiochemistryAcademic Medical CenterUniversity of AmsterdamAmsterdamThe Netherlands
| | - Naomi Van Vlies
- Department of Genetic Metabolic DiseasesAcademic Medical CenterUniversity of AmsterdamAmsterdamThe Netherlands
| | - Ronald J. A. Wanders
- Department of Genetic Metabolic DiseasesAcademic Medical CenterUniversity of AmsterdamAmsterdamThe Netherlands
| | - Frédéric M. Vaz
- Department of Genetic Metabolic DiseasesAcademic Medical CenterUniversity of AmsterdamAmsterdamThe Netherlands
| | - Ben Distel
- Department of Medical BiochemistryAcademic Medical CenterUniversity of AmsterdamAmsterdamThe Netherlands
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29
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Piekarska K, Hardy G, Mol E, van den Burg J, Strijbis K, van Roermund C, van den Berg M, Distel B. The activity of the glyoxylate cycle in peroxisomes of Candida albicans depends on a functional β-oxidation pathway: evidence for reduced metabolite transport across the peroxisomal membrane. Microbiology (Reading) 2008; 154:3061-3072. [DOI: 10.1099/mic.0.2008/020289-0] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Affiliation(s)
- Katarzyna Piekarska
- Department of Medical Biochemistry, Academic Medical Center, Meibergdreef 15, 1105 AZ Amsterdam, The Netherlands
| | - Guy Hardy
- Department of Medical Biochemistry, Academic Medical Center, Meibergdreef 15, 1105 AZ Amsterdam, The Netherlands
| | - Els Mol
- Department of Medical Biochemistry, Academic Medical Center, Meibergdreef 15, 1105 AZ Amsterdam, The Netherlands
| | - Janny van den Burg
- Department of Medical Biochemistry, Academic Medical Center, Meibergdreef 15, 1105 AZ Amsterdam, The Netherlands
| | - Karin Strijbis
- Department of Medical Biochemistry, Academic Medical Center, Meibergdreef 15, 1105 AZ Amsterdam, The Netherlands
| | - Carlo van Roermund
- Department of Genetic Metabolic Diseases, Academic Medical Center, Meibergdreef 15, 1105 AZ Amsterdam, The Netherlands
| | - Marlene van den Berg
- Department of Medical Biochemistry, Academic Medical Center, Meibergdreef 15, 1105 AZ Amsterdam, The Netherlands
| | - Ben Distel
- Department of Medical Biochemistry, Academic Medical Center, Meibergdreef 15, 1105 AZ Amsterdam, The Netherlands
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