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Han L, Pendleton A, Singh A, Xu R, Scott SA, Palma JA, Diebold P, Malarney KP, Brito IL, Chang PV. Chemoproteomic profiling of substrate specificity in gut microbiota-associated bile salt hydrolases. Cell Chem Biol 2024:S2451-9456(24)00210-1. [PMID: 38889717 DOI: 10.1016/j.chembiol.2024.05.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2023] [Revised: 03/25/2024] [Accepted: 05/22/2024] [Indexed: 06/20/2024]
Abstract
The gut microbiome possesses numerous biochemical enzymes that biosynthesize metabolites that impact human health. Bile acids comprise a diverse collection of metabolites that have important roles in metabolism and immunity. The gut microbiota-associated enzyme that is responsible for the gateway reaction in bile acid metabolism is bile salt hydrolase (BSH), which controls the host's overall bile acid pool. Despite the critical role of these enzymes, the ability to profile their activities and substrate preferences remains challenging due to the complexity of the gut microbiota, whose metaproteome includes an immense diversity of protein classes. Using a systems biochemistry approach employing activity-based probes, we have identified gut microbiota-associated BSHs that exhibit distinct substrate preferences, revealing that different microbes contribute to the diversity of the host bile acid pool. We envision that this chemoproteomic approach will reveal how secondary bile acid metabolism controlled by BSHs contributes to the etiology of various inflammatory diseases.
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Affiliation(s)
- Lin Han
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853, USA
| | | | - Adarsh Singh
- Meinig School of Biomedical Engineering, Cornell University, Ithaca, NY 14853, USA
| | - Raymond Xu
- Department of Microbiology and Immunology, Cornell University, Ithaca, NY 14853, USA
| | - Samantha A Scott
- Department of Microbiology and Immunology, Cornell University, Ithaca, NY 14853, USA
| | - Jaymee A Palma
- Smith School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, NY 14853, USA
| | - Peter Diebold
- Department of Microbiology, Cornell University, Ithaca, NY 14853, USA
| | - Kien P Malarney
- Department of Microbiology, Cornell University, Ithaca, NY 14853, USA
| | - Ilana L Brito
- Meinig School of Biomedical Engineering, Cornell University, Ithaca, NY 14853, USA; Cornell Center for Immunology, Cornell University, Ithaca, NY 14853, USA; Cornell Institute of Host-Microbe Interactions and Disease, Cornell University, Ithaca, NY 14853, USA
| | - Pamela V Chang
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853, USA; Department of Microbiology and Immunology, Cornell University, Ithaca, NY 14853, USA; Cornell Center for Immunology, Cornell University, Ithaca, NY 14853, USA; Cornell Institute of Host-Microbe Interactions and Disease, Cornell University, Ithaca, NY 14853, USA; Cornell Center for Innovative Proteomics, Cornell University, Ithaca, NY 14853, USA.
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2
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Liu S, Li W, Chen J, Li M, Geng Y, Liu Y, Wu W. The footprint of gut microbiota in gallbladder cancer: a mechanistic review. Front Cell Infect Microbiol 2024; 14:1374238. [PMID: 38774627 PMCID: PMC11106419 DOI: 10.3389/fcimb.2024.1374238] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2024] [Accepted: 04/22/2024] [Indexed: 05/24/2024] Open
Abstract
Gallbladder cancer (GBC) is the most common malignant tumor of the biliary system with the worst prognosis. Even after radical surgery, the majority of patients with GBC have difficulty achieving a clinical cure. The risk of tumor recurrence remains more than 65%, and the overall 5-year survival rate is less than 5%. The gut microbiota refers to a variety of microorganisms living in the human intestine, including bacteria, viruses and fungi, which profoundly affect the host state of general health, disease and even cancer. Over the past few decades, substantial evidence has supported that gut microbiota plays a critical role in promoting the progression of GBC. In this review, we summarize the functions, molecular mechanisms and recent advances of the intestinal microbiota in GBC. We focus on the driving role of bacteria in pivotal pathways, such as virulence factors, metabolites derived from intestinal bacteria, chronic inflammatory responses and ecological niche remodeling. Additionally, we emphasize the high level of correlation between viruses and fungi, especially EBV and Candida spp., with GBC. In general, this review not only provides a solid theoretical basis for the close relationship between gut microbiota and GBC but also highlights more potential research directions for further research in the future.
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Affiliation(s)
- Shujie Liu
- Joint Program of Nanchang University and Queen Mary University of London, Jiangxi Medical College of Nanchang University, Nanchang, Jiangxi, China
| | - Weijian Li
- Department of Biliary-Pancreatic Surgery, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
- Shanghai Key Laboratory of Biliary Tract Disease Research, Shanghai, China
- State Key Laboratory of Oncogenes and Related Genes, Shanghai Cancer Institute, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
- Shanghai Research Center of Biliary Tract Disease, Shanghai, China
| | - Jun Chen
- Department of Biliary-Pancreatic Surgery, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
- Shanghai Key Laboratory of Biliary Tract Disease Research, Shanghai, China
- State Key Laboratory of Oncogenes and Related Genes, Shanghai Cancer Institute, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
- Shanghai Research Center of Biliary Tract Disease, Shanghai, China
| | - Maolan Li
- Department of Biliary-Pancreatic Surgery, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
- Shanghai Key Laboratory of Biliary Tract Disease Research, Shanghai, China
- State Key Laboratory of Oncogenes and Related Genes, Shanghai Cancer Institute, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
- Shanghai Research Center of Biliary Tract Disease, Shanghai, China
| | - Yajun Geng
- Department of Biliary-Pancreatic Surgery, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
- Shanghai Key Laboratory of Biliary Tract Disease Research, Shanghai, China
- State Key Laboratory of Oncogenes and Related Genes, Shanghai Cancer Institute, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
- Shanghai Research Center of Biliary Tract Disease, Shanghai, China
| | - Yingbin Liu
- Department of Biliary-Pancreatic Surgery, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
- Shanghai Key Laboratory of Biliary Tract Disease Research, Shanghai, China
- State Key Laboratory of Oncogenes and Related Genes, Shanghai Cancer Institute, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
- Shanghai Research Center of Biliary Tract Disease, Shanghai, China
| | - Wenguang Wu
- Department of Biliary-Pancreatic Surgery, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
- Shanghai Key Laboratory of Biliary Tract Disease Research, Shanghai, China
- State Key Laboratory of Oncogenes and Related Genes, Shanghai Cancer Institute, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
- Shanghai Research Center of Biliary Tract Disease, Shanghai, China
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Han L, Pendleton A, Singh A, Xu R, Scott SA, Palma JA, Diebold P, Malarney KP, Brito IL, Chang PV. Chemoproteomic profiling of substrate specificity in gut microbiota-associated bile salt hydrolases. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.01.587558. [PMID: 38617281 PMCID: PMC11014516 DOI: 10.1101/2024.04.01.587558] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/16/2024]
Abstract
The gut microbiome possesses numerous biochemical enzymes that biosynthesize metabolites that impact human health. Bile acids comprise a diverse collection of metabolites that have important roles in metabolism and immunity. The gut microbiota-associated enzyme that is responsible for the gateway reaction in bile acid metabolism is bile salt hydrolase (BSH), which controls the host's overall bile acid pool. Despite the critical role of these enzymes, the ability to profile their activities and substrate preferences remains challenging due to the complexity of the gut microbiota, whose metaproteome includes an immense diversity of protein classes. Using a systems biochemistry approach employing activity-based probes, we have identified gut microbiota-associated BSHs that exhibit distinct substrate preferences, revealing that different microbes contribute to the diversity of the host bile acid pool. We envision that this chemoproteomic approach will reveal how secondary bile acid metabolism controlled by BSHs contributes to the etiology of various inflammatory diseases.
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Affiliation(s)
- Lin Han
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853
| | | | - Adarsh Singh
- Meinig School of Biomedical Engineering, Cornell University, Ithaca, NY 14853
| | - Raymond Xu
- Department of Microbiology and Immunology, Cornell University, Ithaca, NY 14853
| | - Samantha A Scott
- Department of Microbiology and Immunology, Cornell University, Ithaca, NY 14853
| | - Jaymee A Palma
- Smith School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, NY 14853
| | - Peter Diebold
- Department of Microbiology, Cornell University, Ithaca, NY 14853
| | - Kien P Malarney
- Department of Microbiology, Cornell University, Ithaca, NY 14853
| | - Ilana L Brito
- Meinig School of Biomedical Engineering, Cornell University, Ithaca, NY 14853
- Cornell Center for Immunology, Cornell University, Ithaca, NY 14853
- Cornell Institute of Host-Microbe Interactions and Disease, Cornell University, Ithaca, NY 14853
| | - Pamela V Chang
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853
- Department of Microbiology and Immunology, Cornell University, Ithaca, NY 14853
- Cornell Center for Immunology, Cornell University, Ithaca, NY 14853
- Cornell Institute of Host-Microbe Interactions and Disease, Cornell University, Ithaca, NY 14853
- Cornell Center for Innovative Proteomics, Cornell University, Ithaca, NY 14853
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4
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Guo H, Cui J, Li Q, Liang X, Li J, Yang B, Kalds P, Chen Y, Yang Y. A multi-omic assessment of the mechanisms of intestinal microbes used to treat diarrhea in early-weaned lambs. mSystems 2024; 9:e0095323. [PMID: 38193712 PMCID: PMC10878098 DOI: 10.1128/msystems.00953-23] [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: 09/07/2023] [Accepted: 10/07/2023] [Indexed: 01/10/2024] Open
Abstract
Transplant of donor microbiota can significantly alter the structure of the host's intestinal microbiota and alleviate early weaning stress. Screening for alternative-resistant products by transplanting fecal bacteria from healthy lambs is a current research trend in the livestock industry. In the present study, fecal microbiota transplantation was performed in lambs with diarrhea during early weaning. The transplanted fecal microbiota greatly reduced the diarrhea and serum inflammatory factor levels caused by early weaning. Transcriptome sequencing revealed that fecal microbiota transplantation alleviated colonic inflammation and increased the expression of colonic ion transport proteins. In addition, the levels of Streptococcus, Enterococcus, and Escherichia Shigella decreased in the jejunum, cecum, and colon of the lambs; meanwhile, the levels of Bifidobacterium and multiple secondary bile acids, such as ursodeoxycholic acid, increased in the colon. Furthermore, the abundance of Bifidobacterium was significantly negatively correlated with the diarrhea index. The fecal microbiota transplantation reshaped the intestinal microbiota of early-weaned lambs, protected the intestinal physiology and immune barrier, and reduced weaning stress. In addition to making available bacteriological products for controlling intestinal inflammation in young lambs, this study offers a theoretical framework and technical system for the mechanisms by which microbiota transplantation regulates intestinal health in young lambs.IMPORTANCEBefore weaning, the digestive system of lambs is not well developed; hence, its resistance to infectious diseases is weak. Under intensive feeding systems, lambs can easily be stressed and the risk of bacterial infection is high, which causes diarrhea, which in turn may cause mortality and significant economic losses to the livestock industry. With the elimination of antibiotics in animal feed, the incidence of mortality due to intestinal illnesses in lambs has gradually increased. There are several types of probiotics routinely used in young animals, but the effects and processes of their usage have only been assessed in monogastric animals. The lack of data on ruminants, particularly sheep, has severely hampered the process of efficient and healthy sheep breeding. Therefore, there is an urgent need to identify effective and safe functional supplements for lambs.
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Affiliation(s)
- Hongran Guo
- Key Laboratory of Animal Genetics, Breeding and Reproduction of Shaanxi Province, College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi Province, China
| | - Jiuzeng Cui
- Key Laboratory of Animal Genetics, Breeding and Reproduction of Shaanxi Province, College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi Province, China
| | - Qian Li
- Key Laboratory of Animal Genetics, Breeding and Reproduction of Shaanxi Province, College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi Province, China
| | - Xuhui Liang
- Key Laboratory of Animal Genetics, Breeding and Reproduction of Shaanxi Province, College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi Province, China
| | - Junda Li
- Key Laboratory of Animal Genetics, Breeding and Reproduction of Shaanxi Province, College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi Province, China
| | - Bohua Yang
- Key Laboratory of Animal Genetics, Breeding and Reproduction of Shaanxi Province, College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi Province, China
| | - Peter Kalds
- Key Laboratory of Animal Genetics, Breeding and Reproduction of Shaanxi Province, College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi Province, China
| | - Yulin Chen
- Key Laboratory of Animal Genetics, Breeding and Reproduction of Shaanxi Province, College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi Province, China
| | - Yuxin Yang
- Key Laboratory of Animal Genetics, Breeding and Reproduction of Shaanxi Province, College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi Province, China
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5
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Weigert Muñoz A, Zhao W, Sieber SA. Monitoring host-pathogen interactions using chemical proteomics. RSC Chem Biol 2024; 5:73-89. [PMID: 38333198 PMCID: PMC10849124 DOI: 10.1039/d3cb00135k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2023] [Accepted: 11/09/2023] [Indexed: 02/10/2024] Open
Abstract
With the rapid emergence and the dissemination of microbial resistance to conventional chemotherapy, the shortage of novel antimicrobial drugs has raised a global health threat. As molecular interactions between microbial pathogens and their mammalian hosts are crucial to establish virulence, pathogenicity, and infectivity, a detailed understanding of these interactions has the potential to reveal novel therapeutic targets and treatment strategies. Bidirectional molecular communication between microbes and eukaryotes is essential for both pathogenic and commensal organisms to colonise their host. In particular, several devastating pathogens exploit host signalling to adjust the expression of energetically costly virulent behaviours. Chemical proteomics has emerged as a powerful tool to interrogate the protein interaction partners of small molecules and has been successfully applied to advance host-pathogen communication studies. Here, we present recent significant progress made by this approach and provide a perspective for future studies.
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Affiliation(s)
- Angela Weigert Muñoz
- Center for Functional Protein Assemblies, Department of Bioscience, TUM School of Natural Sciences, Technical University of Munich Ernst-Otto-Fischer-Straße 8 D-85748 Garching Germany
| | - Weining Zhao
- College of Pharmacy, Shenzhen Technology University Shenzhen 518118 China
| | - Stephan A Sieber
- Center for Functional Protein Assemblies, Department of Bioscience, TUM School of Natural Sciences, Technical University of Munich Ernst-Otto-Fischer-Straße 8 D-85748 Garching Germany
- Helmholtz Institute for Pharmaceutical Research Saarland (HIPS) Germany
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6
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Han L, Chang PV. Activity-based protein profiling in microbes and the gut microbiome. Curr Opin Chem Biol 2023; 76:102351. [PMID: 37429085 PMCID: PMC10527501 DOI: 10.1016/j.cbpa.2023.102351] [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: 12/15/2022] [Revised: 05/21/2023] [Accepted: 05/24/2023] [Indexed: 07/12/2023]
Abstract
Activity-based protein profiling (ABPP) is a powerful chemical approach for probing protein function and enzymatic activity in complex biological systems. This strategy typically utilizes activity-based probes that are designed to bind a specific protein, amino acid residue, or protein family and form a covalent bond through a reactivity-based warhead. Subsequent analysis by mass spectrometry-based proteomic platforms that involve either click chemistry or affinity-based labeling to enrich for the tagged proteins enables identification of protein function and enzymatic activity. ABPP has facilitated elucidation of biological processes in bacteria, discovery of new antibiotics, and characterization of host-microbe interactions within physiological contexts. This review will focus on recent advances and applications of ABPP in bacteria and complex microbial communities.
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Affiliation(s)
- Lin Han
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853, USA
| | - Pamela V Chang
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853, USA; Department of Microbiology and Immunology, Cornell University, Ithaca, NY 14853, USA; Cornell Center for Immunology, Cornell University, Ithaca, NY 14853, USA; Cornell Institute of Host-Microbe Interactions and Disease, Cornell University, Ithaca, NY 14853, USA.
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7
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Malarney KP, Chang PV. Chemoproteomic Approaches for Unraveling Prokaryotic Biology. Isr J Chem 2023; 63:e202200076. [PMID: 37842282 PMCID: PMC10575470 DOI: 10.1002/ijch.202200076] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Indexed: 03/07/2023]
Abstract
Bacteria are ubiquitous lifeforms with important roles in the environment, biotechnology, and human health. Many of the functions that bacteria perform are mediated by proteins and enzymes, which catalyze metabolic transformations of small molecules and modifications of proteins. To better understand these biological processes, chemical proteomic approaches, including activity-based protein profiling, have been developed to interrogate protein function and enzymatic activity in physiologically relevant contexts. Here, chemoproteomic strategies and technological advances for studying bacterial physiology, pathogenesis, and metabolism are discussed. The development of chemoproteomic approaches for characterizing protein function and enzymatic activity within bacteria remains an active area of research, and continued innovations are expected to provide breakthroughs in understanding bacterial biology.
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Affiliation(s)
- Kien P Malarney
- Department of Microbiology, Cornell University, Ithaca, NY 14853 (USA)
| | - Pamela V Chang
- Department of Microbiology and Immunology, Cornell University, Ithaca, NY 14853 (USA)
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853 (USA)
- Cornell Center for Immunology, Cornell University, Ithaca, NY 14853 (USA)
- Cornell Institute of Host-Microbe Interactions and Disease, Cornell University, Ithaca, NY 14853 (USA)
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8
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Disarming the pathogen. Nat Chem Biol 2023; 19:5-6. [PMID: 36175660 DOI: 10.1038/s41589-022-01133-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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9
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Yang X, Zhao X, Chen V, Hang HC. Chemical proteomic analysis of bile acid-protein targets in Enterococcus faecium. RSC Chem Biol 2022; 3:1397-1402. [PMID: 36544573 PMCID: PMC9709779 DOI: 10.1039/d2cb00178k] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2022] [Accepted: 09/19/2022] [Indexed: 12/24/2022] Open
Abstract
Bile acids are important gut microbiota metabolites that regulate both host and microbial functions. To identify the direct protein targets of bile acids in Enterococcus, we synthesized and validated the activity of a lithocholic acid (LCA) photoaffinity reporter, x-alk-LCA-3. Chemical proteomics of x-alk-LCA-3 in E. faecium Com15 reveals many candidate LCA-interacting proteins, which are involved in cell well synthesis, transcriptional regulation and metabolism. To validate the utility of bile acid photoaffinity labeling, we characterized a putative bile salt hydrolase (BSH) crosslinked by x-alk-LCA-3, and demonstrated that this BSH was effective in converting taurolithocholic acid (TLCA) to LCA in E. faecium and in vitro. Chemical proteomics should afford new opportunities to characterize bile acid-protein targets and mechanisms of action in the future.
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Affiliation(s)
- Xinglin Yang
- Department of Immunology and Microbiology, Scripps Research La Jolla California 92037 USA
| | - Xiaohui Zhao
- Department of Immunology and Microbiology, Scripps Research La Jolla California 92037 USA
| | - Victor Chen
- Laboratory of Chemical Biology and Microbial Pathogenesis, The Rockefeller University New York New York 10065 USA
| | - Howard C Hang
- Department of Immunology and Microbiology, Scripps Research La Jolla California 92037 USA
- Department of Chemistry, Scripps Research La Jolla California 92037 USA
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10
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Forster ER, Yang X, Tai AK, Hang HC, Shen A. Identification of a Bile Acid-Binding Transcription Factor in Clostridioides difficile Using Chemical Proteomics. ACS Chem Biol 2022; 17:3086-3099. [PMID: 36279369 PMCID: PMC10518218 DOI: 10.1021/acschembio.2c00463] [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] [Indexed: 01/20/2023]
Abstract
Clostridioides difficile is a Gram-positive anaerobic bacterium that is the leading cause of hospital-acquired gastroenteritis in the US. In the gut milieu, C. difficile encounters microbiota-derived, growth-inhibiting bile acids that are thought to be a significant mechanism of colonization resistance. While the levels of certain bile acids in the gut correlate with susceptibility to C. difficile infection, their molecular targets in C. difficile remain unknown. In this study, we sought to use chemical proteomics to identify bile acid-interacting proteins in C. difficile. Using photoaffinity bile acid probes and chemical proteomics, we identified a previously uncharacterized MerR family protein, CD3583 (now BapR), as a putative bile acid-sensing transcription regulator. Our data indicate that BapR specifically binds to and is stabilized by lithocholic acid (LCA) in C. difficile. Although loss of BapR did not affect C. difficile's sensitivity to LCA, ΔbapR cells elongated more in the presence of LCA compared to wild-type cells. Transcriptomics revealed that BapR regulates several gene clusters, with the expression of the mdeA-cd3573 locus being specifically de-repressed in the presence of LCA in a BapR-dependent manner. Electrophoretic mobility shift assays revealed that BapR directly binds to the mdeA promoter region. Because mdeA is involved in amino acid-related sulfur metabolism and the mdeA-cd3573 locus encodes putative transporters, we propose that BapR senses a gastrointestinal tract-specific small molecule, LCA, as an environmental cue for metabolic adaptation.
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Affiliation(s)
- Emily R Forster
- Graduate School of Biomedical Sciences, Tufts University, Boston, Massachusetts 02111, United States
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, Massachusetts 02111, United States
| | - Xinglin Yang
- Department of Immunology and Microbiology, Scripps Research, La Jolla, California 92037, United States
| | - Albert K Tai
- Department of Immunology, Tufts University School of Medicine, Boston, Massachusetts 02111, United States
- Data Intensive Studies Center, Tufts University, Medford, Massachusetts 02155, United States
| | - Howard C Hang
- Department of Immunology and Microbiology, Scripps Research, La Jolla, California 92037, United States
- Department of Chemistry, Scripps Research, La Jolla, California 92037, United States
| | - Aimee Shen
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, Massachusetts 02111, United States
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