1
|
Ye D, Nguyen PT, Bourgault S, Couture M. The heme binding protein ChuX is a regulator of heme degradation by the ChuS protein in Escherichia coli O157:H7. J Inorg Biochem 2024; 256:112575. [PMID: 38678912 DOI: 10.1016/j.jinorgbio.2024.112575] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2024] [Revised: 04/17/2024] [Accepted: 04/23/2024] [Indexed: 05/01/2024]
Abstract
Escherichia coli O157:H7 possesses an 8-gene cluster (chu genes) that contains genes involved in heme transport and processing from the human host. Among the chu genes, four encode cytoplasmic proteins (ChuS, ChuX, ChuY and ChuW). ChuX was previously shown to be a heme binding protein and to assist ChuW in heme degradation under anaerobic conditions. The purpose of this work was to investigate if ChuX works in concert with ChuS, which is a protein able to degrade heme by a non-canonical mechanism and release the iron from the porphyrin under aerobic conditions using hydrogen peroxide as the oxidant. We showed that when the heme-bound ChuX and apo-ChuS protein are mixed, heme is efficiently transferred from ChuX to ChuS. Heme-bound ChuX displayed a peroxidase activity with ABTS and H2O2 but not heme-bound ChuS, which is an efficient test to determine the protein to which heme is bound in the ChuS-ChuX complex. We found that ChuX protects heme from chemical oxidation and that it has no heme degradation activity by itself. Unexpectedly, we found that ChuX inhibits heme degradation by ChuS and stops the reaction at an early intermediate. We determined using surface plasmon resonance that ChuX interacts with ChuS and that it forms a relatively stable complex. These results indicate that ChuX in addition to its heme transfer activity is a regulator of ChuS activity, a function that was not described before for any of the heme carrier protein that delivers heme to heme degradation enzymes.
Collapse
Affiliation(s)
- Danrong Ye
- Department of Biochemistry, Microbiology and Bioinformatics, Université Laval, Quebec City, QC, Canada; Institut de Biologie Intégrative et des Systèmes (IBIS) and PROTEO, Université Laval, Quebec city, QC, Canada; Quebec Network for Research on Protein Function, Engineering and Applications (PROTEO), Montreal, QC, Canada
| | - Phuong Trang Nguyen
- Quebec Network for Research on Protein Function, Engineering and Applications (PROTEO), Montreal, QC, Canada; Departement of Chemistry, Université du Québec à Montréal, Montreal, QC, Canada
| | - Steve Bourgault
- Quebec Network for Research on Protein Function, Engineering and Applications (PROTEO), Montreal, QC, Canada; Departement of Chemistry, Université du Québec à Montréal, Montreal, QC, Canada
| | - Manon Couture
- Department of Biochemistry, Microbiology and Bioinformatics, Université Laval, Quebec City, QC, Canada; Institut de Biologie Intégrative et des Systèmes (IBIS) and PROTEO, Université Laval, Quebec city, QC, Canada; Quebec Network for Research on Protein Function, Engineering and Applications (PROTEO), Montreal, QC, Canada.
| |
Collapse
|
2
|
Liao CH, Lu HF, Yang CW, Yeh TY, Lin YT, Yang TC. HemU and TonB1 contribute to hemin acquisition in Stenotrophomonas maltophilia. Front Cell Infect Microbiol 2024; 14:1380976. [PMID: 38596648 PMCID: PMC11002078 DOI: 10.3389/fcimb.2024.1380976] [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: 02/02/2024] [Accepted: 03/12/2024] [Indexed: 04/11/2024] Open
Abstract
Introduction The hemin acquisition system is composed of an outer membrane TonB-dependent transporter that internalizes hemin into the periplasm, periplasmic hemin-binding proteins to shuttle hemin, an inner membrane transporter that transports hemin into the cytoplasm, and cytoplasmic heme oxygenase to release iron. Fur and HemP are two known regulators involved in the regulation of hemin acquisition. The hemin acquisition system of Stenotrophomonas maltophilia is poorly understood, with the exception of HemA as a TonB-dependent transporter for hemin uptake. Methods Putative candidates responsible for hemin acquisition were selected via a homolog search and a whole-genome survey of S. maltophilia. Operon verification was performed by reverse transcription-polymerase chain reaction. The involvement of candidate genes in hemin acquisition was assessed using an in-frame deletion mutant construct and iron utilization assays. The transcript levels of candidate genes were determined using quantitative polymerase chain reaction. Results Smlt3896-hemU-exbB2-exbD2-tonB2 and tonB1-exbB1-exbD1a-exbD1b operons were selected as candidates for hemin acquisition. Compared with the parental strain, hemU and tonB1 mutants displayed a defect in their ability to use hemin as the sole iron source for growth. However, hemin utilization by the Smlt3896 and tonB2 mutants was comparable to that of the parental strain. HemA expression was repressed by Fur in iron-replete conditions and derepressed in iron-depleted conditions. HemP negatively regulated hemA expression. Like hemA, hemU was repressed by Fur in iron-replete conditions; however, hemU was moderately derepressed in response to iron-depleted stress and fully derepressed when hemin was present. Unlike hemA and hemU, the TonB1-exbB1-exbD1a-exbD1b operon was constitutively expressed, regardless of the iron level or the presence of hemin, and Fur and HemP had no influence on its expression. Conclusion HemA, HemU, and TonB1 contribute to hemin acquisition in S. maltophilia. Fur represses the expression of hemA and hemU in iron-replete conditions. HemA expression is regulated by low iron levels, and HemP acts as a negative regulator of this regulatory circuit. HemU expression is regulated by low iron and hemin levels in a hemP-dependent manner.
Collapse
Affiliation(s)
- Chun-Hsing Liao
- Division of Infectious Disease, Far Eastern Memorial Hospital, New Taipei City, Taiwan
- Department of Medicine, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Hsu-Feng Lu
- Department of Medical Laboratory Science and Biotechnology, Asia University, Taichung, Taiwan
| | - Ching-Wei Yang
- Department of Biotechnology and Laboratory Science in Medicine, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Ting-Yu Yeh
- Department of Biotechnology and Laboratory Science in Medicine, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Yi-Tsung Lin
- Division of Infectious Diseases, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan
- School of Medicine, National Yang Chiao Tung University, Taipei, Taiwan
| | - Tsuey-Ching Yang
- Department of Biotechnology and Laboratory Science in Medicine, National Yang Ming Chiao Tung University, Taipei, Taiwan
| |
Collapse
|
3
|
Keith AD, Sawyer EB, Choy DCY, Xie Y, Biggs GS, Klein OJ, Brear PD, Wales DJ, Barker PD. Combining experiment and energy landscapes to explore anaerobic heme breakdown in multifunctional hemoproteins. Phys Chem Chem Phys 2024; 26:695-712. [PMID: 38053511 DOI: 10.1039/d3cp03897a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/07/2023]
Abstract
To survive, many pathogens extract heme from their host organism and break down the porphyrin scaffold to sequester the Fe2+ ion via a heme oxygenase. Recent studies have revealed that certain pathogens can anaerobically degrade heme. Our own research has shown that one such pathway proceeds via NADH-dependent heme degradation, which has been identified in a family of hemoproteins from a range of bacteria. HemS, from Yersinia enterocolitica, is the main focus of this work, along with HmuS (Yersinia pestis), ChuS (Escherichia coli) and ShuS (Shigella dysenteriae). We combine experiments, Energy Landscape Theory, and a bioinformatic investigation to place these homologues within a wider phylogenetic context. A subset of these hemoproteins are known to bind certain DNA promoter regions, suggesting not only that they can catalytically degrade heme, but that they are also involved in transcriptional modulation responding to heme flux. Many of the bacterial species responsible for these hemoproteins (including those that produce HemS, ChuS and ShuS) are known to specifically target oxygen-depleted regions of the gastrointestinal tract. A deeper understanding of anaerobic heme breakdown processes exploited by these pathogens could therefore prove useful in the development of future strategies for disease prevention.
Collapse
Affiliation(s)
- Alasdair D Keith
- Yusuf Hamied Department of Chemistry, University of Cambridge, Cambridge, CB2 1EW, UK.
| | - Elizabeth B Sawyer
- Yusuf Hamied Department of Chemistry, University of Cambridge, Cambridge, CB2 1EW, UK.
| | - Desmond C Y Choy
- Yusuf Hamied Department of Chemistry, University of Cambridge, Cambridge, CB2 1EW, UK.
| | - Yuhang Xie
- Yusuf Hamied Department of Chemistry, University of Cambridge, Cambridge, CB2 1EW, UK.
| | - George S Biggs
- Yusuf Hamied Department of Chemistry, University of Cambridge, Cambridge, CB2 1EW, UK.
| | - Oskar James Klein
- Yusuf Hamied Department of Chemistry, University of Cambridge, Cambridge, CB2 1EW, UK.
| | - Paul D Brear
- Department of Biochemistry, University of Cambridge, Sanger Building, Cambridge CB2 1GA, UK
| | - David J Wales
- Yusuf Hamied Department of Chemistry, University of Cambridge, Cambridge, CB2 1EW, UK.
| | - Paul D Barker
- Yusuf Hamied Department of Chemistry, University of Cambridge, Cambridge, CB2 1EW, UK.
| |
Collapse
|
4
|
Weaver BR, Perkins LJ, Fernandez Candelaria FO, Burstyn JN, Buller AR. Molecular Determinants of Efficient Cobalt-Substituted Hemoprotein Production in E. coli. ACS Synth Biol 2023; 12:3669-3679. [PMID: 37963151 DOI: 10.1021/acssynbio.3c00481] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2023]
Abstract
Exchanging the native iron of heme for other metals yields artificial metalloproteins with new properties for spectroscopic studies and biocatalysis. Recently, we reported a method for the biosynthesis and incorporation of a non-natural metallocofactor, cobalt protoporphyrin IX (CoPPIX), into hemoproteins using the common laboratory strain Escherichia coli BL21(DE3). This discovery inspired us to explore the determinants of metal specificity for metallocofactor biosynthesis in E. coli. Herein, we report detailed kinetic analysis of the ferrochelatase responsible for metal insertion, EcHemH (E. coli ferrochelatase). This enzyme exhibits a small, less than 2-fold preference for Fe2+ over the non-native Co2+ substrate in vitro. To test how mutations impact EcHemH, we used a surrogate metal specificity screen to identify variants with altered metal insertion preferences. This engineering process led to a variant with an ∼30-fold shift in specificity toward Co2+. When assayed in vivo, however, the impact of this mutation is small compared to the effects of alteration of the external metal concentrations. These data suggest that incorporation of cobalt into PPIX is enabled by the native promiscuity of EcHemH coupled with BL21's impaired ability to maintain transition-metal homeostasis. With this knowledge, we generated a method for CoPPIX production in rich media, which yields cobalt-substituted hemoproteins with >95% cofactor purity and yields comparable to standard expression protocols for the analogous native hemoproteins.
Collapse
Affiliation(s)
- Brian R Weaver
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
| | - Lydia J Perkins
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
| | | | - Judith N Burstyn
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
| | - Andrew R Buller
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
| |
Collapse
|
5
|
Han S, Guo K, Wang W, Tao YJ, Gao H. Bacterial TANGO2 homologs are heme-trafficking proteins that facilitate biosynthesis of cytochromes c. mBio 2023; 14:e0132023. [PMID: 37462360 PMCID: PMC10470608 DOI: 10.1128/mbio.01320-23] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2023] [Accepted: 06/05/2023] [Indexed: 09/02/2023] Open
Abstract
Heme, an essential molecule for virtually all living organisms, acts primarily as a cofactor in a large number of proteins. However, how heme is mobilized from the site of synthesis to the locations where hemoproteins are assembled remains largely unknown in cells, especially bacterial ones. In this study, with Shewanella oneidensis as the model, we identified HtpA (SO0126) as a heme-trafficking protein and homolog of TANGO2 proteins found in eukaryotes. We showed that HtpA homologs are widely distributed in all domains of living organisms and have undergone parallel evolution. In its absence, the cytochrome (cyt) c content and catalase activity decreased significantly. We further showed that both HtpA and representative TANGO2 proteins bind heme with 1:1 stoichiometry and a relatively low dissociation constant. Protein interaction analyses substantiated that HtpA directly interacts with the cytochrome c maturation system. Our findings shed light on cross-membrane transport of heme in bacteria and extend the understanding of TANGO2 proteins. IMPORTANCE The intracellular trafficking of heme, an essential cofactor for hemoproteins, remains underexplored even in eukaryotes, let alone bacteria. Here we developed a high-throughput method by which HtpA, a homolog of eukaryotic TANGO2 proteins, was identified to be a heme-binding protein that enhances cytochrome c biosynthesis and catalase activity in Shewanella oneidensis. HtpA interacts with the cytochrome c biosynthesis system directly, supporting that this protein, like TANGO2, functions in intracellular heme trafficking. HtpA homologs are widely distributed, but a large majority of them were found to be non-exchangeable, likely a result of parallel evolution. By substantiating the heme-trafficking nature of HtpA and its eukaryotic homologs, our findings provide general insight into the heme-trafficking process and highlight the functional conservation along evolution in all living organisms.
Collapse
Affiliation(s)
- Sirui Han
- Institute of Microbiology, College of Life Sciences, Zhejiang University, Hangzhou, Zhejiang, China
| | - Kailun Guo
- Institute of Microbiology, College of Life Sciences, Zhejiang University, Hangzhou, Zhejiang, China
| | - Wei Wang
- Institute of Microbiology, College of Life Sciences, Zhejiang University, Hangzhou, Zhejiang, China
| | - Yizhi J. Tao
- Department of BioSciences, Rice University, Houston, Texas, USA
| | - Haichun Gao
- Institute of Microbiology, College of Life Sciences, Zhejiang University, Hangzhou, Zhejiang, China
| |
Collapse
|
6
|
Multamäki E, García de Fuentes A, Sieryi O, Bykov A, Gerken U, Ranzani A, Köhler J, Meglinski I, Möglich A, Takala H. Optogenetic Control of Bacterial Expression by Red Light. ACS Synth Biol 2022; 11:3354-3367. [PMID: 35998606 PMCID: PMC9594775 DOI: 10.1021/acssynbio.2c00259] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
In optogenetics, as in nature, sensory photoreceptors serve to control cellular processes by light. Bacteriophytochrome (BphP) photoreceptors sense red and far-red light via a biliverdin chromophore and, in response, cycle between the spectroscopically, structurally, and functionally distinct Pr and Pfr states. BphPs commonly belong to two-component systems that control the phosphorylation of cognate response regulators and downstream gene expression through histidine kinase modules. We recently demonstrated that the paradigm BphP from Deinococcus radiodurans exclusively acts as a phosphatase but that its photosensory module can control the histidine kinase activity of homologous receptors. Here, we apply this insight to reprogram two widely used setups for bacterial gene expression from blue-light to red-light control. The resultant pREDusk and pREDawn systems allow gene expression to be regulated down and up, respectively, uniformly under red light by 100-fold or more. Both setups are realized as portable, single plasmids that encode all necessary components including the biliverdin-producing machinery. The triggering by red light affords high spatial resolution down to the single-cell level. As pREDusk and pREDawn respond sensitively to red light, they support multiplexing with optogenetic systems sensitive to other light colors. Owing to the superior tissue penetration of red light, the pREDawn system can be triggered at therapeutically safe light intensities through material layers, replicating the optical properties of the skin and skull. Given these advantages, pREDusk and pREDawn enable red-light-regulated expression for diverse use cases in bacteria.
Collapse
Affiliation(s)
- Elina Multamäki
- Department
of Anatomy, University of Helsinki, Helsinki 00014, Finland
| | | | - Oleksii Sieryi
- Optoelectronics
and Measurement Techniques, University of
Oulu, Oulu 90014, Finland
| | - Alexander Bykov
- Optoelectronics
and Measurement Techniques, University of
Oulu, Oulu 90014, Finland
| | - Uwe Gerken
- Lehrstuhl
für Spektroskopie weicher Materie, Universität Bayreuth, Bayreuth 95447, Germany
| | | | - Jürgen Köhler
- Lehrstuhl
für Spektroskopie weicher Materie, Universität Bayreuth, Bayreuth 95447, Germany
| | - Igor Meglinski
- Optoelectronics
and Measurement Techniques, University of
Oulu, Oulu 90014, Finland,College
of Engineering and Physical Sciences, Aston
University, Birmingham B4 7ET, U.K.
| | - Andreas Möglich
- Lehrstuhl
für Biochemie, Photobiochemie, Universität
Bayreuth, Bayreuth 95447, Germany,. Phone: +49 921 55
7835
| | - Heikki Takala
- Department
of Anatomy, University of Helsinki, Helsinki 00014, Finland,Department
of Biological and Environmental Science, Nanoscience Center, University of Jyvaskyla, Jyvaskyla 40014, Finland,. Phone: +358 46 923 6211
| |
Collapse
|
7
|
de Lima VM, Batista BB, da Silva Neto JF. The Regulatory Protein ChuP Connects Heme and Siderophore-Mediated Iron Acquisition Systems Required for Chromobacterium violaceum Virulence. Front Cell Infect Microbiol 2022; 12:873536. [PMID: 35646721 PMCID: PMC9131926 DOI: 10.3389/fcimb.2022.873536] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2022] [Accepted: 03/30/2022] [Indexed: 11/22/2022] Open
Abstract
Chromobacterium violaceum is an environmental Gram-negative beta-proteobacterium that causes systemic infections in humans. C. violaceum uses siderophore-based iron acquisition systems to overcome the host-imposed iron limitation, but its capacity to use other iron sources is unknown. In this work, we characterized ChuPRSTUV as a heme utilization system employed by C. violaceum to explore an important iron reservoir in mammalian hosts, free heme and hemoproteins. We demonstrate that the chuPRSTUV genes comprise a Fur-repressed operon that is expressed under iron limitation. The chu operon potentially encodes a small regulatory protein (ChuP), an outer membrane TonB-dependent receptor (ChuR), a heme degradation enzyme (ChuS), and an inner membrane ABC transporter (ChuTUV). Our nutrition growth experiments using C. violaceum chu deletion mutants revealed that, with the exception of chuS, all genes of the chu operon are required for heme and hemoglobin utilization in C. violaceum. The mutant strains without chuP displayed increased siderophore halos on CAS plate assays. Significantly, we demonstrate that ChuP connects heme and siderophore utilization by acting as a positive regulator of chuR and vbuA, which encode the TonB-dependent receptors for the uptake of heme (ChuR) and the siderophore viobactin (VbuA). Our data favor a model of ChuP as a heme-binding post-transcriptional regulator. Moreover, our virulence data in a mice model of acute infection demonstrate that C. violaceum uses both heme and siderophore for iron acquisition during infection, with a preference for siderophores over the Chu heme utilization system.
Collapse
|
8
|
Abstract
Urinary tract infection (UTI) is the most common type of urogenital disease. UTI affects the urethra, bladder, ureter, and kidney. A total of 13.3% of women, 2.3% of men, and 3.4% of children in the United States will require treatment for UTI. Traditionally, bladder (cystitis) and kidney (pyelonephritis) infections are considered independently. However, both infections induce host defenses that are either shared or coordinated across the urinary tract. Here, we review the chemical and biophysical mechanisms of bacteriostasis, which limit the duration and severity of the illness. Urinary bacteria attempt to overcome each of these defenses, complicating description of the natural history of UTI.
Collapse
Affiliation(s)
| | - Anne-Catrin Uhlemann
- Department of Medicine and Pathology and Urology, Columbia University, New York, NY, USA;
| | - Jonathan Barasch
- Department of Medicine and Pathology and Urology, Columbia University, New York, NY, USA;
| |
Collapse
|
9
|
Brimberry M, Toma MA, Hines KM, Lanzilotta WN. HutW from Vibrio cholerae Is an Anaerobic Heme-Degrading Enzyme with Unique Functional Properties. Biochemistry 2021; 60:699-710. [PMID: 33600151 DOI: 10.1021/acs.biochem.0c00950] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Increasing antibiotic resistance, and a growing recognition of the importance of the human microbiome, demand that new therapeutic targets be identified. Characterization of metabolic pathways that are unique to enteric pathogens represents a promising approach. Iron is often the rate-limiting factor for growth, and Vibrio cholerae, the causative agent of cholera, has been shown to contain numerous genes that function in the acquisition of iron from the environment. Included in this arsenal of genes are operons dedicated to obtaining iron from heme and heme-containing proteins. Given the persistence of cholera, an important outstanding question is whether V. cholerae is capable of anaerobic heme degradation as was recently reported for enterohemorrhagic Escherichia coli O157:H7. In this work, we demonstrate that HutW from V. cholerae is a radical S-adenosylmethionine methyl transferase involved in the anaerobic opening of the porphyrin ring of heme. However, in contrast to the enzyme ChuW, found in enterohemorrhagic E. coli O157:H7, there are notable differences in the mechanism and products of the HutW reaction. Of particular interest are data that demonstrate HutW will catalyze ring opening as well as tetrapyrrole reduction and can utilize reduced nicotinamide adenine dinucleotide phosphate as an electron source. The biochemical and biophysical properties of HutW are presented, and the evolutionary implications are discussed.
Collapse
|
10
|
Wang J, Guo Q, Li X, Wang X, Liu L. The Arabidopsis locus AT3G03890 encodes a dimeric β-barrel protein implicated in heme degradation. Biochem J 2020; 477:BCJ20200712. [PMID: 33284325 DOI: 10.1042/bcj20200712] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2020] [Revised: 12/03/2020] [Accepted: 12/04/2020] [Indexed: 02/24/2024]
Abstract
Plant tetrapyrroles, including heme and bilins, are synthesized in plastids. Heme oxygenase (HO) catalyzes the oxidative cleavage of heme to the linear tetrapyrrole biliverdin as the initial step in bilin biosynthesis. Besides the canonical α-helical HO that is conserved from prokaryotes to human, a subfamily of non-canonical dimeric β-barrel HO has been found in bacteria. In this work, we discovered that the Arabidopsis locus AT3G03890 encodes a dimeric β-barrel protein that is structurally related to the putative non-canonical HO and is located in chloroplasts. The recombinant protein was able to bind and degrade heme in a manner different from known HO proteins. Crystal structure of the heme-protein complex reveals that the heme-binding site is in the interdimer interface and the heme iron is coordinated by a fixed water molecule. Our results identify a new protein that may function additionally in the tetrapyrrole biosynthetic pathway.
Collapse
Affiliation(s)
| | - Qi Guo
- Institute of Botany, Chinease Academy of Sciences, Beijing, China
| | - Xiaoyi Li
- Institute of Botany, Chinease Academy of Sciences, Beijing, China
| | | | - Lin Liu
- Anhui University, Hefei, China
| |
Collapse
|
11
|
Hopper CP, De La Cruz LK, Lyles KV, Wareham LK, Gilbert JA, Eichenbaum Z, Magierowski M, Poole RK, Wollborn J, Wang B. Role of Carbon Monoxide in Host-Gut Microbiome Communication. Chem Rev 2020; 120:13273-13311. [PMID: 33089988 DOI: 10.1021/acs.chemrev.0c00586] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Nature is full of examples of symbiotic relationships. The critical symbiotic relation between host and mutualistic bacteria is attracting increasing attention to the degree that the gut microbiome is proposed by some as a new organ system. The microbiome exerts its systemic effect through a diverse range of metabolites, which include gaseous molecules such as H2, CO2, NH3, CH4, NO, H2S, and CO. In turn, the human host can influence the microbiome through these gaseous molecules as well in a reciprocal manner. Among these gaseous molecules, NO, H2S, and CO occupy a special place because of their widely known physiological functions in the host and their overlap and similarity in both targets and functions. The roles that NO and H2S play have been extensively examined by others. Herein, the roles of CO in host-gut microbiome communication are examined through a discussion of (1) host production and function of CO, (2) available CO donors as research tools, (3) CO production from diet and bacterial sources, (4) effect of CO on bacteria including CO sensing, and (5) gut microbiome production of CO. There is a large amount of literature suggesting the "messenger" role of CO in host-gut microbiome communication. However, much more work is needed to begin achieving a systematic understanding of this issue.
Collapse
Affiliation(s)
- Christopher P Hopper
- Institute for Experimental Biomedicine, University Hospital Wuerzburg, Wuerzburg, Bavaria DE 97080, Germany.,Department of Medicinal Chemistry, College of Pharmacy, The University of Florida, Gainesville, Florida 32611, United States
| | - Ladie Kimberly De La Cruz
- Department of Chemistry & Center for Diagnostics and Therapeutics, Georgia State University, Atlanta, Georgia 30303, United States
| | - Kristin V Lyles
- Department of Biology, Georgia State University, Atlanta, Georgia 30303, United States
| | - Lauren K Wareham
- The Vanderbilt Eye Institute and Department of Ophthalmology & Visual Sciences, The Vanderbilt University Medical Center and School of Medicine, Nashville, Tennessee 37232, United States
| | - Jack A Gilbert
- Department of Pediatrics, Scripps Institution of Oceanography, University of California San Diego, La Jolla, California 92093, United States
| | - Zehava Eichenbaum
- Department of Biology, Georgia State University, Atlanta, Georgia 30303, United States
| | - Marcin Magierowski
- Cellular Engineering and Isotope Diagnostics Laboratory, Department of Physiology, Jagiellonian University Medical College, Cracow PL 31-531, Poland
| | - Robert K Poole
- Department of Molecular Biology and Biotechnology, The University of Sheffield, Firth Court, Sheffield S10 2TN, U.K
| | - Jakob Wollborn
- Department of Anesthesiology and Critical Care, Medical Center, University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg DE 79085, Germany.,Department of Anesthesiology, Perioperative and Pain Management, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115, United States
| | - Binghe Wang
- Department of Chemistry & Center for Diagnostics and Therapeutics, Georgia State University, Atlanta, Georgia 30303, United States
| |
Collapse
|
12
|
Holmes A, Pritchard L, Hedley P, Morris J, McAteer SP, Gally DL, Holden NJ. A high-throughput genomic screen identifies a role for the plasmid-borne type II secretion system of Escherichia coli O157:H7 (Sakai) in plant-microbe interactions. Genomics 2020; 112:4242-4253. [PMID: 32663607 DOI: 10.1016/j.ygeno.2020.07.021] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Revised: 06/15/2020] [Accepted: 07/09/2020] [Indexed: 01/16/2023]
Abstract
Shiga-toxigenic Escherichia coli (STEC) is often transmitted into food via fresh produce plants, where it can cause disease. To identify early interaction factors for STEC on spinach, a high-throughput positive-selection system was used. A bacterial artificial chromosome (BAC) clone library for isolate Sakai was screened in four successive rounds of short-term (2 h) interaction with spinach roots, and enriched loci identified by microarray. A Bayesian hierarchical model produced 115 CDS credible candidates, comprising seven contiguous genomic regions. Of the two candidate regions selected for functional assessment, the pO157 plasmid-encoded type two secretion system (T2SS) promoted interactions, while a chaperone-usher fimbrial gene cluster (loc6) did not. The T2SS promoted bacterial binding to spinach and appeared to involve the EtpD secretin protein. Furthermore, the T2SS genes, etpD and etpC, were expressed at a plant-relevant temperature of 18 °C, and etpD was expressed in planta by E. coli Sakai on spinach plants.
Collapse
Affiliation(s)
- Ashleigh Holmes
- Cellular and Molecular Sciences, James Hutton Institute, Dundee, DD2 5DA, UK
| | - Leighton Pritchard
- Cellular and Molecular Sciences, James Hutton Institute, Dundee, DD2 5DA, UK.; Strathclyde Institute for Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow, G4 0RE, UK
| | - Peter Hedley
- Cellular and Molecular Sciences, James Hutton Institute, Dundee, DD2 5DA, UK
| | - Jenny Morris
- Cellular and Molecular Sciences, James Hutton Institute, Dundee, DD2 5DA, UK
| | - Sean P McAteer
- The Roslin Institute, Division of Infection and Immunity, University of Edinburgh, R(D)SVS, The Roslin Institute Building, Easter Bush, EH25 9RG, UK
| | - David L Gally
- The Roslin Institute, Division of Infection and Immunity, University of Edinburgh, R(D)SVS, The Roslin Institute Building, Easter Bush, EH25 9RG, UK
| | - Nicola J Holden
- Cellular and Molecular Sciences, James Hutton Institute, Dundee, DD2 5DA, UK.; SRUC, Northern Faculty, Aberdeen, AB21 9YA, UK..
| |
Collapse
|
13
|
Knippel RJ, Wexler AG, Miller JM, Beavers WN, Weiss A, de Crécy-Lagard V, Edmonds KA, Giedroc DP, Skaar EP. Clostridioides difficile Senses and Hijacks Host Heme for Incorporation into an Oxidative Stress Defense System. Cell Host Microbe 2020; 28:411-421.e6. [PMID: 32526159 DOI: 10.1016/j.chom.2020.05.015] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Revised: 04/02/2020] [Accepted: 05/19/2020] [Indexed: 12/18/2022]
Abstract
Clostridioides difficile infection of the colon leads to severe inflammation and damage to the gastrointestinal epithelium due to the production of potent toxins. This inflammatory tissue damage causes the liberation of high concentrations of host heme at infection sites. Here, we identify the C. difficile heme-sensing membrane protein system (HsmRA) and show that this operon induces a protective response that repurposes heme to counteract antimicrobial oxidative stress responses. HsmR senses vertebrate heme, leading to increased expression of the hsmRA operon and subsequent deployment of HsmA to capture heme and reduce redox damage caused by inflammatory mediators of protection and antibiotic therapy. Strains with inactivated hsmR or hsmA have increased sensitivity to redox-active compounds and reduced colonization persistence in a murine model of relapse C. difficile infection. These results define a mechanism exploited by C. difficile to repurpose toxic heme within the inflamed gut as a shield against antimicrobial compounds.
Collapse
Affiliation(s)
- Reece J Knippel
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, TN, USA; Vanderbilt Institute for Infection, Immunology and Inflammation, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Aaron G Wexler
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, TN, USA; Vanderbilt Institute for Infection, Immunology and Inflammation, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Jeanette M Miller
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, TN, USA; Vanderbilt Institute for Infection, Immunology and Inflammation, Vanderbilt University Medical Center, Nashville, TN, USA
| | - William N Beavers
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, TN, USA; Vanderbilt Institute for Infection, Immunology and Inflammation, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Andy Weiss
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, TN, USA; Vanderbilt Institute for Infection, Immunology and Inflammation, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Valérie de Crécy-Lagard
- Department of Microbiology and Cell Science, Institute of Food and Agricultural Sciences and Genetics Institute, University of Florida, Gainesville, FL, USA
| | | | - David P Giedroc
- Department of Chemistry, Indiana University, Bloomington, IN, USA
| | - Eric P Skaar
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, TN, USA; Vanderbilt Institute for Infection, Immunology and Inflammation, Vanderbilt University Medical Center, Nashville, TN, USA.
| |
Collapse
|
14
|
Ganley JG, D'Ambrosio HK, Shieh M, Derbyshire ER. Coculturing of Mosquito-Microbiome Bacteria Promotes Heme Degradation in Elizabethkingia anophelis. Chembiochem 2020; 21:1279-1284. [PMID: 31845464 DOI: 10.1002/cbic.201900675] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2019] [Indexed: 12/31/2022]
Abstract
Anopheles mosquito microbiomes are intriguing ecological niches. Within the gut, microbes adapt to oxidative stress due to heme and iron after blood meals. Although metagenomic sequencing has illuminated spatial and temporal fluxes of microbiome populations, limited data exist on microbial growth dynamics. Here, we analyze growth interactions between a dominant microbiome species, Elizabethkingia anophelis, and other Anopheles-associated bacteria. We find E. anophelis inhibits a Pseudomonas sp. via an antimicrobial-independent mechanism and observe biliverdins, heme degradation products, upregulated in cocultures. Purification and characterization of E. anophelis HemS demonstrates heme degradation, and we observe hemS expression is upregulated when cocultured with Pseudomonas sp. This study reveals a competitive microbial interaction between mosquito-associated bacteria and characterizes the stimulation of heme degradation in E. anophelis when grown with Pseudomonas sp.
Collapse
Affiliation(s)
- Jack G Ganley
- Department of Chemistry, Duke University, 124 Science Drive, Durham, NC, 27708, USA
| | - Hannah K D'Ambrosio
- Department of Chemistry, Duke University, 124 Science Drive, Durham, NC, 27708, USA
| | - Meg Shieh
- Department of Chemistry, Duke University, 124 Science Drive, Durham, NC, 27708, USA
| | - Emily R Derbyshire
- Department of Chemistry, Duke University, 124 Science Drive, Durham, NC, 27708, USA.,Department of Molecular Genetics and Microbiology, Duke University Medical Center, 213 Research Drive, Durham, NC, 27710, USA
| |
Collapse
|
15
|
Yuan C, Zhang Y, Tan H, Li X, Chen G, Jia Z. ONIOM investigations of the heme degradation mechanism by MhuD: the critical function of heme ruffling. Phys Chem Chem Phys 2020; 22:8817-8826. [DOI: 10.1039/c9cp05868k] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A unique ruffling conformation of hydroxyheme in MhuD inhibits its “on-site” monooxygenation but induces “remote-site” dioxygenation.
Collapse
Affiliation(s)
- Chang Yuan
- College of Chemistry
- Key Laboratories of Theoretical and Computational Photochemistry
- Ministry of Education
- Beijing Normal University
- Beijing
| | - Ying Zhang
- College of Chemistry
- Key Laboratories of Theoretical and Computational Photochemistry
- Ministry of Education
- Beijing Normal University
- Beijing
| | - Hongwei Tan
- College of Chemistry
- Key Laboratories of Theoretical and Computational Photochemistry
- Ministry of Education
- Beijing Normal University
- Beijing
| | - Xichen Li
- College of Chemistry
- Key Laboratories of Theoretical and Computational Photochemistry
- Ministry of Education
- Beijing Normal University
- Beijing
| | - Guangju Chen
- College of Chemistry
- Key Laboratories of Theoretical and Computational Photochemistry
- Ministry of Education
- Beijing Normal University
- Beijing
| | - Zongchao Jia
- Department of Biomedical and Molecular Sciences
- Queen's University
- Kingston
- Ontario
- Canada
| |
Collapse
|
16
|
Liu T, Mukosera GT, Blood AB. The role of gasotransmitters in neonatal physiology. Nitric Oxide 2019; 95:29-44. [PMID: 31870965 DOI: 10.1016/j.niox.2019.12.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2019] [Revised: 11/07/2019] [Accepted: 12/17/2019] [Indexed: 12/12/2022]
Abstract
The gasotransmitters, nitric oxide (NO), hydrogen sulfide (H2S), and carbon monoxide (CO), are endogenously-produced volatile molecules that perform signaling functions throughout the body. In biological tissues, these small, lipid-permeable molecules exist in free gaseous form for only seconds or less, and thus they are ideal for paracrine signaling that can be controlled rapidly by changes in their rates of production or consumption. In addition, tissue concentrations of the gasotransmitters are influenced by fluctuations in the level of O2 and reactive oxygen species (ROS). The normal transition from fetus to newborn involves a several-fold increase in tissue O2 tensions and ROS, and requires rapid morphological and functional adaptations to the extrauterine environment. This review summarizes the role of gasotransmitters as it pertains to newborn physiology. Particular focus is given to the vasculature, ventilatory, and gastrointestinal systems, each of which uniquely illustrate the function of gasotransmitters in the birth transition and newborn periods. Moreover, given the relative lack of studies on the role that gasotransmitters play in the newborn, particularly that of H2S and CO, important gaps in knowledge are highlighted throughout the review.
Collapse
Affiliation(s)
- Taiming Liu
- Department of Pediatrics, Division of Neonatology, Loma Linda University School of Medicine, Loma Linda, CA, 92354, USA
| | - George T Mukosera
- Department of Pediatrics, Division of Neonatology, Loma Linda University School of Medicine, Loma Linda, CA, 92354, USA
| | - Arlin B Blood
- Department of Pediatrics, Division of Neonatology, Loma Linda University School of Medicine, Loma Linda, CA, 92354, USA; Lawrence D. Longo Center for Perinatal Biology, Loma Linda University School of Medicine, Loma Linda, CA, 92354, USA.
| |
Collapse
|
17
|
Vukomanovic D, Jia Z, Nakatsu K, Smith GN, Ozolinš TRS. Riboflavin and pyrroloquinoline quinone generate carbon monoxide in the presence of tissue microsomes or recombinant human cytochrome P-450 oxidoreductase: implications for possible roles in gasotransmission. Can J Physiol Pharmacol 2019; 98:336-342. [PMID: 31825651 DOI: 10.1139/cjpp-2019-0376] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Carbon monoxide (CO), an endogenously produced gasotransmitter, regulates inflammation and vascular tone, suggesting that delivery of CO may be therapeutically useful for pathologies like preeclampsia where CO insufficiency is implicated. Our strategy is to identify chemicals that increase the activity of endogenous CO-producing enzymes, including cytochrome P-450 oxidoreductase (CPR). Realizing that both riboflavin and pyrroloquinoline quinone (PQQ) are relatively nontoxic, even at high doses, and that they share chemical properties with toxic CO activators that we previously identified, our goal was to determine whether riboflavin or PQQ could stimulate CO production. Riboflavin and PQQ were incubated in sealed vessels with rat and human tissue extracts and CO generation was measured with headspace-gas chromatography. Riboflavin and PQQ increased CO production ∼60% in rat spleen microsomes. In rat brain microsomes, riboflavin and PQQ increased respective CO production approximately fourfold and twofold compared to baseline. CO production by human placenta microsomes increased fourfold with riboflavin and fivefold with PQQ. In the presence of recombinant human CPR, CO production was threefold greater with PQQ than with riboflavin. These observations demonstrate for the first time that riboflavin and PQQ facilitate tissue-specific CO production with significant contributions from CPR. We propose a novel biochemical role for these nutrients in gastransmission.
Collapse
Affiliation(s)
- Dragic Vukomanovic
- Department of Biomedical and Molecular Sciences, Queen's University, Kingston, ON K7L 3N6, Canada.,Department of Obstetrics and Gynaecology, Kingston General Hospital, Kingston, ON K7L 3N6, Canada
| | - Zongchao Jia
- Department of Biomedical and Molecular Sciences, Queen's University, Kingston, ON K7L 3N6, Canada
| | - Kanji Nakatsu
- Department of Biomedical and Molecular Sciences, Queen's University, Kingston, ON K7L 3N6, Canada
| | - Graeme N Smith
- Department of Biomedical and Molecular Sciences, Queen's University, Kingston, ON K7L 3N6, Canada.,Department of Obstetrics and Gynaecology, Kingston General Hospital, Kingston, ON K7L 3N6, Canada
| | - Terence R S Ozolinš
- Department of Biomedical and Molecular Sciences, Queen's University, Kingston, ON K7L 3N6, Canada
| |
Collapse
|
18
|
Mathew LG, Beattie NR, Pritchett C, Lanzilotta WN. New Insight into the Mechanism of Anaerobic Heme Degradation. Biochemistry 2019; 58:4641-4654. [PMID: 31652058 DOI: 10.1021/acs.biochem.9b00841] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
ChuW, ChuX, and ChuY are contiguous genes downstream from a single promoter that are expressed in the enteric pathogen Escherichia coli O157:H7 when iron is limiting. These genes, and the corresponding proteins, are part of a larger heme uptake and utilization operon that is common to several other enteric pathogens, such as Vibrio cholerae. The aerobic degradation of heme has been well characterized in humans and several pathogenic bacteria, including E. coli O157:H7, but only recently was it shown that ChuW catalyzes the anaerobic degradation of heme to release iron and produce a reactive tetrapyrrole termed "anaerobilin". ChuY has been shown to function as an anaerobilin reductase, in a role that parallels biliverdin reductase. In this work we have employed biochemical and biophysical approaches to further interrogate the mechanism of the anaerobic degradation of heme. We demonstrate that the iron atom of the heme does not participate in the catalytic mechanism of ChuW and that S-adenosyl-l-methionine binding induces conformational changes that favor catalysis. In addition, we show that ChuX and ChuY have synergistic and additive effects on the turnover rate of ChuW. Finally, we have found that ChuS is an effective source of heme or protoporphyrin IX for ChuW under anaerobic conditions. These data indicate that ChuS may have dual functionality in vivo. Specifically, ChuS serves as a heme oxygenase during aerobic metabolism of heme but functions as a cytoplasmic heme storage protein under anaerobic conditions, akin to what has been shown for PhuS (45% sequence identity) from Pseudomonas aeruginosa.
Collapse
Affiliation(s)
- Liju G Mathew
- Department of Biochemistry and Molecular Biology & Center for Metalloenzyme Studies , University of Georgia , Athens , Georgia 30602 , United States
| | - Nathaniel R Beattie
- Department of Biochemistry and Molecular Biology & Center for Metalloenzyme Studies , University of Georgia , Athens , Georgia 30602 , United States
| | - Clayton Pritchett
- Department of Biochemistry and Molecular Biology & Center for Metalloenzyme Studies , University of Georgia , Athens , Georgia 30602 , United States
| | - William N Lanzilotta
- Department of Biochemistry and Molecular Biology & Center for Metalloenzyme Studies , University of Georgia , Athens , Georgia 30602 , United States
| |
Collapse
|
19
|
Adam SM, Wijeratne GB, Rogler PJ, Diaz DE, Quist DA, Liu JJ, Karlin KD. Synthetic Fe/Cu Complexes: Toward Understanding Heme-Copper Oxidase Structure and Function. Chem Rev 2018; 118:10840-11022. [PMID: 30372042 PMCID: PMC6360144 DOI: 10.1021/acs.chemrev.8b00074] [Citation(s) in RCA: 132] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Heme-copper oxidases (HCOs) are terminal enzymes on the mitochondrial or bacterial respiratory electron transport chain, which utilize a unique heterobinuclear active site to catalyze the 4H+/4e- reduction of dioxygen to water. This process involves a proton-coupled electron transfer (PCET) from a tyrosine (phenolic) residue and additional redox events coupled to transmembrane proton pumping and ATP synthesis. Given that HCOs are large, complex, membrane-bound enzymes, bioinspired synthetic model chemistry is a promising approach to better understand heme-Cu-mediated dioxygen reduction, including the details of proton and electron movements. This review encompasses important aspects of heme-O2 and copper-O2 (bio)chemistries as they relate to the design and interpretation of small molecule model systems and provides perspectives from fundamental coordination chemistry, which can be applied to the understanding of HCO activity. We focus on recent advancements from studies of heme-Cu models, evaluating experimental and computational results, which highlight important fundamental structure-function relationships. Finally, we provide an outlook for future potential contributions from synthetic inorganic chemistry and discuss their implications with relevance to biological O2-reduction.
Collapse
Affiliation(s)
- Suzanne M. Adam
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - Gayan B. Wijeratne
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - Patrick J. Rogler
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - Daniel E. Diaz
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - David A. Quist
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - Jeffrey J. Liu
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - Kenneth D. Karlin
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, United States
| |
Collapse
|
20
|
Sebastián VP, Salazar GA, Coronado-Arrázola I, Schultz BM, Vallejos OP, Berkowitz L, Álvarez-Lobos MM, Riedel CA, Kalergis AM, Bueno SM. Heme Oxygenase-1 as a Modulator of Intestinal Inflammation Development and Progression. Front Immunol 2018; 9:1956. [PMID: 30258436 PMCID: PMC6143658 DOI: 10.3389/fimmu.2018.01956] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2018] [Accepted: 08/08/2018] [Indexed: 12/19/2022] Open
Abstract
Heme Oxygenase 1 (HMOX1) is an enzyme that catalyzes the reaction that degrades the heme group contained in several important proteins, such as hemoglobin, myoglobin, and cytochrome p450. The enzymatic reaction catalyzed by HMOX1 generates Fe2+, biliverdin and CO. It has been shown that HMOX1 activity and the by-product CO can downmodulate the damaging immune response in several models of intestinal inflammation as a result of pharmacological induction of HMOX1 expression and the administration of non-toxic amounts of CO. Inflammatory Bowel Diseases, which includes Crohn's Disease (CD) and Ulcerative Colitis (UC), are one of the most studied ailments associated to HMOX1 effects. However, microbiota imbalances and infections are also important factors influencing the occurrence of acute and chronic intestinal inflammation, where HMOX1 activity may play a major role. As part of this article we discuss the immune modulatory capacity of HMOX1 during IBD, as well during the infections and interactions with the microbiota that contribute to this inflammatory disease.
Collapse
Affiliation(s)
- Valentina P. Sebastián
- Millennium Institute on Immunology and Immunotherapy, Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Geraldyne A. Salazar
- Millennium Institute on Immunology and Immunotherapy, Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Irenice Coronado-Arrázola
- Millennium Institute on Immunology and Immunotherapy, Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Bárbara M. Schultz
- Millennium Institute on Immunology and Immunotherapy, Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Omar P. Vallejos
- Millennium Institute on Immunology and Immunotherapy, Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Loni Berkowitz
- Millennium Institute on Immunology and Immunotherapy, Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
- Departamento de Gastroenterología, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Manuel M. Álvarez-Lobos
- Millennium Institute on Immunology and Immunotherapy, Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
- Departamento de Gastroenterología, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Claudia A. Riedel
- Millennium Institute on Immunology and Immunotherapy, Facultad de Ciencias de la Vida, Departamento de Ciencias Biológicas, Universidad Andrés Bello, Santiago, Chile
| | - Alexis M. Kalergis
- Millennium Institute on Immunology and Immunotherapy, Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
- Departamento de Endocrinología, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Susan M. Bueno
- Millennium Institute on Immunology and Immunotherapy, Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| |
Collapse
|
21
|
Lyles KV, Eichenbaum Z. From Host Heme To Iron: The Expanding Spectrum of Heme Degrading Enzymes Used by Pathogenic Bacteria. Front Cell Infect Microbiol 2018; 8:198. [PMID: 29971218 PMCID: PMC6018153 DOI: 10.3389/fcimb.2018.00198] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2018] [Accepted: 05/28/2018] [Indexed: 01/02/2023] Open
Abstract
Iron is an essential nutrient for many bacteria. Since the metal is highly sequestered in host tissues, bound predominantly to heme, pathogenic bacteria often take advantage of heme uptake and degradation mechanisms to acquire iron during infection. The most common mechanism of releasing iron from heme is through oxidative degradation by heme oxygenases (HOs). In addition, an increasing number of proteins that belong to two distinct structural families have been implicated in aerobic heme catabolism. Finally, an enzyme that degrades heme anaerobically was recently uncovered, further expanding the mechanisms for bacterial heme degradation. In this analysis, we cover the spectrum and recent advances in heme degradation by infectious bacteria. We briefly explain heme oxidation by the two groups of recognized HOs to ground readers before focusing on two new types of proteins that are reported to be involved in utilization of heme iron. We discuss the structure and enzymatic function of proteins representing these groups, their biological context, and how they are regulated to provide a more complete look at their cellular role.
Collapse
Affiliation(s)
- Kristin V Lyles
- Biology, Georgia State University, Atlanta, GA, United States
| | | |
Collapse
|
22
|
Uchida T, Funamizu T, Chen M, Tanaka Y, Ishimori K. Heme Binding to Porphobilinogen Deaminase from Vibrio cholerae Decelerates the Formation of 1-Hydroxymethylbilane. ACS Chem Biol 2018; 13:750-760. [PMID: 29360345 DOI: 10.1021/acschembio.7b00934] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Porphobilinogen deaminase (PBGD) is an enzyme that catalyzes the formation of hydroxymethylbilane, a tetrapyrrole intermediate, during heme biosynthesis through the stepwise polymerization of four molecules of porphobilinogen. PBGD from Vibrio cholerae was expressed in Escherichia coli and characterized in this study. Unexpectedly, spectroscopic measurements revealed that PBGD bound one equivalent of heme with a dissociation constant of 0.33 ± 0.01 μM. The absorption and resonance Raman spectra suggested that heme is a mixture of the 5-coordinate and 6-coordinate hemes. Mutational studies indicated that the 5-coordinate heme possessed Cys105 as a heme axial ligand, and His227 was coordinated to form the 6-coordinate heme. Upon heme binding, the deamination activity decreased by approximately 15%. The crystal structure of PBGD revealed that His227 was located near Cys105, but the side chain of His227 did not point toward Cys105. The addition of the cyanide ion to heme-PBGD abolished the effect of heme binding on the enzymatic activity. Therefore, coordination of His227 to heme appeared to induce reorientation of the domains containing Cys105, leading to a decrease in the enzymatic activity. This is the first report indicating that the PBGD activity is controlled by heme, the final product of heme biosynthesis. This finding improves our understanding of the mechanism by which heme biosynthesis is regulated.
Collapse
Affiliation(s)
- Takeshi Uchida
- Department of Chemistry, Faculty of Science, Hokkaido University, Sapporo 060-0810, Japan
- Graduate School of Chemical Sciences and Engineering, Hokkaido University, Sapporo 060-8628, Japan
| | - Takumi Funamizu
- Graduate School of Chemical Sciences and Engineering, Hokkaido University, Sapporo 060-8628, Japan
| | - Minghao Chen
- Graduate School of Life Science, Hokkaido University, Sapporo 060-0810, Japan
| | - Yoshikazu Tanaka
- Faculty of Advanced Life Science, Hokkaido University, Sapporo 060-0810, Japan
- PRESTO, Japan Science and Technology Agency, Sapporo 060-0810, Japan
| | - Koichiro Ishimori
- Department of Chemistry, Faculty of Science, Hokkaido University, Sapporo 060-0810, Japan
- Graduate School of Chemical Sciences and Engineering, Hokkaido University, Sapporo 060-8628, Japan
| |
Collapse
|
23
|
Kim H, Chaurasia AK, Kim T, Choi J, Ha SC, Kim D, Kim KK. Structural and functional study of ChuY from Escherichia coli strain CFT073. Biochem Biophys Res Commun 2016; 482:1176-1182. [PMID: 27919686 DOI: 10.1016/j.bbrc.2016.12.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2016] [Accepted: 12/02/2016] [Indexed: 10/20/2022]
Abstract
The uropathogenic Escherichia coli strain CFT073 contains multiple iron and heme transport systems, which facilitate infection of the host urinary tract. To elucidate the molecular and cellular function of ChuY, a hypothetical gene in the heme degradation/utilization pathway, we solved the crystal structure of ChuY at 2.4 Å resolution. ChuY has high structural homology with human biliverdin and flavin reductase. We confirmed that ChuY has flavin mononucleotide (FMN) reductase activity, using NAD(P)H as a cofactor, and shows porphyrin ring binding affinity. A chuY deletion-insertion strain showed reduced survival potential compared to wild-type and complemented strains in mammalian cells. Current results suggest ChuY acts as a reductase in heme homeostasis to maintain the virulence potential of E. coli CFT073.
Collapse
Affiliation(s)
- Hun Kim
- Department of Molecular Cell Biology, Sungkyunkwan University School of Medicine, Suwon, Gyeonggi 16419, South Korea
| | - Akhilesh Kumar Chaurasia
- Department of Molecular Cell Biology, Sungkyunkwan University School of Medicine, Suwon, Gyeonggi 16419, South Korea
| | - Truc Kim
- Department of Molecular Cell Biology, Sungkyunkwan University School of Medicine, Suwon, Gyeonggi 16419, South Korea
| | - Jongkeun Choi
- Department of Cosmetic Science, Chungwoon University, Hongseong, Chungnam 32244, South Korea
| | - Sung Chul Ha
- Pohang Accelerator Laboratory, Pohang, Gyeongbuk 37673, South Korea
| | - Doyoun Kim
- Department of Molecular Cell Biology, Sungkyunkwan University School of Medicine, Suwon, Gyeonggi 16419, South Korea
| | - Kyeong Kyu Kim
- Department of Molecular Cell Biology, Sungkyunkwan University School of Medicine, Suwon, Gyeonggi 16419, South Korea.
| |
Collapse
|
24
|
Radical new paradigm for heme degradation in Escherichia coli O157:H7. Proc Natl Acad Sci U S A 2016; 113:12138-12143. [PMID: 27791000 DOI: 10.1073/pnas.1603209113] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
All of the heme-degrading enzymes that have been characterized to date require molecular oxygen as a cosubstrate. Escherichia coli O157:H7 has been shown to express heme uptake and transport proteins, as well as use heme as an iron source. This enteric pathogen colonizes the anaerobic space of the lower intestine in mammals, yet no mechanism for anaerobic heme degradation has been reported. Herein we provide evidence for an oxygen-independent heme-degradation pathway. Specifically, we demonstrate that ChuW is a radical S-adenosylmethionine methyltransferase that catalyzes a radical-mediated mechanism facilitating iron liberation and the production of the tetrapyrrole product we termed "anaerobilin." We further demonstrate that anaerobilin can be used as a substrate by ChuY, an enzyme that is coexpressed with ChuW in vivo along with the heme uptake machinery. Our findings are discussed in terms of the competitive advantage this system provides for enteric bacteria, particularly those that inhabit an anaerobic niche in the intestines.
Collapse
|
25
|
Sigala PA, Morante K, Tsumoto K, Caaveiro JMM, Goldberg DE. In-Cell Enzymology To Probe His-Heme Ligation in Heme Oxygenase Catalysis. Biochemistry 2016; 55:4836-49. [PMID: 27490825 DOI: 10.1021/acs.biochem.6b00562] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Heme oxygenase (HO) is a ubiquitous enzyme with key roles in inflammation, cell signaling, heme disposal, and iron acquisition. HO catalyzes the oxidative conversion of heme to biliverdin (BV) using a conserved histidine to coordinate the iron atom of bound heme. This His-heme interaction has been regarded as being essential for enzyme activity, because His-to-Ala mutants fail to convert heme to biliverdin in vitro. We probed a panel of proximal His mutants of cyanobacterial, human, and plant HO enzymes using a live-cell activity assay based on heterologous co-expression in Escherichia coli of each HO mutant and a fluorescent biliverdin biosensor. In contrast to in vitro studies with purified proteins, we observed that multiple HO mutants retained significant activity within the intracellular environment of bacteria. X-ray crystallographic structures of human HO1 H25R with bound heme and additional functional studies suggest that HO mutant activity inside these cells does not involve heme ligation by a proximal amino acid. Our study reveals unexpected plasticity in the active site binding interactions with heme that can support HO activity within cells, suggests important contributions by the surrounding active site environment to HO catalysis, and can guide efforts to understand the evolution and divergence of HO function.
Collapse
Affiliation(s)
- Paul A Sigala
- Departments of Medicine and Molecular Microbiology, Washington University School of Medicine , St. Louis, Missouri 63110, United States
| | - Koldo Morante
- Department of Bioengineering, Graduate School of Engineering, The University of Tokyo , Bunkyo-ku, Tokyo 113-8654, Japan
| | - Kouhei Tsumoto
- Department of Bioengineering, Graduate School of Engineering, The University of Tokyo , Bunkyo-ku, Tokyo 113-8654, Japan.,Medical Proteomics Laboratory, Institute of Medical Science, The University of Tokyo , Minato-ku, Tokyo 108-8639, Japan
| | - Jose M M Caaveiro
- Department of Bioengineering, Graduate School of Engineering, The University of Tokyo , Bunkyo-ku, Tokyo 113-8654, Japan
| | - Daniel E Goldberg
- Departments of Medicine and Molecular Microbiology, Washington University School of Medicine , St. Louis, Missouri 63110, United States
| |
Collapse
|
26
|
Choby JE, Skaar EP. Heme Synthesis and Acquisition in Bacterial Pathogens. J Mol Biol 2016; 428:3408-28. [PMID: 27019298 PMCID: PMC5125930 DOI: 10.1016/j.jmb.2016.03.018] [Citation(s) in RCA: 196] [Impact Index Per Article: 24.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2016] [Revised: 03/16/2016] [Accepted: 03/17/2016] [Indexed: 02/06/2023]
Abstract
Bacterial pathogens require the iron-containing cofactor heme to cause disease. Heme is essential to the function of hemoproteins, which are involved in energy generation by the electron transport chain, detoxification of host immune effectors, and other processes. During infection, bacterial pathogens must synthesize heme or acquire heme from the host; however, host heme is sequestered in high-affinity hemoproteins. Pathogens have evolved elaborate strategies to acquire heme from host sources, particularly hemoglobin, and both heme acquisition and synthesis are important for pathogenesis. Paradoxically, excess heme is toxic to bacteria and pathogens must rely on heme detoxification strategies. Heme is a key nutrient in the struggle for survival between host and pathogen, and its study has offered significant insight into the molecular mechanisms of bacterial pathogenesis.
Collapse
Affiliation(s)
- Jacob E Choby
- Department of Pathology, Microbiology, & Immunology, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Eric P Skaar
- Department of Pathology, Microbiology, & Immunology, Vanderbilt University School of Medicine, Nashville, TN, USA; Tennessee Valley Healthcare System, U.S. Department of Veterans Affairs, Nashville, TN, USA.
| |
Collapse
|
27
|
Maharshak N, Ryu HS, Fan TJ, Onyiah JC, Schulz S, Otterbein SL, Wong R, Hansen JJ, Otterbein LE, Carroll IM, Plevy SE. Escherichia coli heme oxygenase modulates host innate immune responses. Microbiol Immunol 2016; 59:452-65. [PMID: 26146866 DOI: 10.1111/1348-0421.12282] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2014] [Revised: 06/24/2015] [Accepted: 06/28/2015] [Indexed: 12/13/2022]
Abstract
Induction of mammalian heme oxygenase (HO)-1 and exposure of animals to carbon monoxide (CO) ameliorates experimental colitis. When enteric bacteria, including Escherichia coli, are exposed to low iron conditions, they express an HO-like enzyme, chuS, and metabolize heme into iron, biliverdin and CO. Given the abundance of enteric bacteria residing in the intestinal lumen, our postulate was that commensal intestinal bacteria may be a significant source of CO and those that express chuS and other Ho-like molecules suppress inflammatory immune responses through release of CO. According to real-time PCR, exposure of mice to CO results in changes in enteric bacterial composition and increases E. coli 16S and chuS DNA. Moreover, the severity of experimental colitis correlates positively with E. coli chuS expression in IL-10 deficient mice. To explore functional roles, E. coli were genetically modified to overexpress chuS or the chuS gene was deleted. Co-culture of chuS-overexpressing E. coli with bone marrow-derived macrophages resulted in less IL-12p40 and greater IL-10 secretion than in wild-type or chuS-deficient E. coli. Mice infected with chuS-overexpressing E. coli have more hepatic CO and less serum IL-12 p40 than mice infected with chuS-deficient E. coli. Thus, CO alters the composition of the commensal intestinal microbiota and expands populations of E. coli that harbor the chuS gene. These bacteria are capable of attenuating innate immune responses through expression of chuS. Bacterial HO-like molecules and bacteria-derived CO may represent novel targets for therapeutic intervention in inflammatory conditions.
Collapse
Affiliation(s)
- Nitsan Maharshak
- Department of Medicine and Center for GI Biology and Diseases, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, 27599.,Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, 27599.,Department of Gastroenterology and Liver Diseases, Tel Aviv Medical Center, Affiliated to the Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, 6997801, Israel
| | - Hyungjin Sally Ryu
- Department of Medicine and Center for GI Biology and Diseases, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, 27599
| | - Ting-Jia Fan
- Department of Medicine and Center for GI Biology and Diseases, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, 27599
| | - Joseph C Onyiah
- Department of Medicine and Center for GI Biology and Diseases, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, 27599.,Division of Gastroenterology and Hepatology, Department of Medicine, University of Colorado, Aurora, CO and Denver VA Medical Center, Denver, Colorado, 80220
| | - Stephanie Schulz
- Department of Pediatrics, Division of Neonatal and Developmental Medicine, Stanford University School of Medicine, Palo Alto, California, 94305
| | - Sherrie L Otterbein
- Department of Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, 02115, USA
| | - Ron Wong
- Department of Pediatrics, Division of Neonatal and Developmental Medicine, Stanford University School of Medicine, Palo Alto, California, 94305
| | - Jonathan J Hansen
- Department of Medicine and Center for GI Biology and Diseases, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, 27599.,Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, 27599
| | - Leo E Otterbein
- Department of Pediatrics, Division of Neonatal and Developmental Medicine, Stanford University School of Medicine, Palo Alto, California, 94305
| | - Ian M Carroll
- Department of Medicine and Center for GI Biology and Diseases, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, 27599
| | - Scott E Plevy
- Department of Medicine and Center for GI Biology and Diseases, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, 27599.,Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, 27599
| |
Collapse
|
28
|
Sachla AJ, Ouattara M, Romero E, Agniswamy J, Weber IT, Gadda G, Eichenbaum Z. In vitro heme biotransformation by the HupZ enzyme from Group A streptococcus. Biometals 2016; 29:593-609. [PMID: 27154580 DOI: 10.1007/s10534-016-9937-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2016] [Accepted: 05/01/2016] [Indexed: 01/14/2023]
Abstract
In Group A streptococcus (GAS), the metallorepressor MtsR regulates iron homeostasis. Here we describe a new MtsR-repressed gene, which we named hupZ (heme utilization protein). A recombinant HupZ protein was purified bound to heme from Escherichia coli grown in the presence of 5-aminolevulinic acid and iron. HupZ specifically binds heme with stoichiometry of 1:1. The addition of NADPH to heme-bound HupZ (in the presence of cytochrome P450 reductase, NADPH-regeneration system and catalase) triggered progressive decrease of the HupZ Soret band and the appearance of an absorption peak at 660 nm that was resistance to hydrolytic conditions. No spectral changes were observed when ferredoxin and ferredoxin reductase were used as redox partners. Differential spectroscopy with myoglobin or with the ferrous chelator, ferrozine, confirmed that carbon monoxide and free iron are produced during the reaction. ApoHupZ was crystallized as a homodimer with a split β-barrel conformation in each monomer comprising six β strands and three α helices. This structure resembles the split β-barrel domain shared by the members of a recently described family of heme degrading enzymes. However, HupZ is smaller and lacks key residues found in the proteins of the latter group. Phylogenetic analysis places HupZ on a clade separated from those for previously described heme oxygenases. In summary, we have identified a new GAS enzyme-containing split β-barrel and capable of heme biotransformation in vitro; to the best of our knowledge, this is the first enzyme among Streptococcus species with such activity.
Collapse
Affiliation(s)
- Ankita J Sachla
- Department of Biology, College of Arts and Sciences, Georgia State University, P.O. Box 4010, Atlanta, GA, 30302-4010, USA
| | - Mahamoudou Ouattara
- Department of Biology, College of Arts and Sciences, Georgia State University, P.O. Box 4010, Atlanta, GA, 30302-4010, USA
| | - Elvira Romero
- Department of Chemistry, College of Arts and Sciences, Georgia State University, Atlanta, GA, 30302-3965, USA
| | - Johnson Agniswamy
- Department of Biology, College of Arts and Sciences, Georgia State University, P.O. Box 4010, Atlanta, GA, 30302-4010, USA
| | - Irene T Weber
- Department of Biology, College of Arts and Sciences, Georgia State University, P.O. Box 4010, Atlanta, GA, 30302-4010, USA.,Department of Chemistry, College of Arts and Sciences, Georgia State University, Atlanta, GA, 30302-3965, USA.,Center for Biotechnology and Drug Design, Georgia State University, Atlanta, GA, 30303, USA
| | - Giovanni Gadda
- Department of Biology, College of Arts and Sciences, Georgia State University, P.O. Box 4010, Atlanta, GA, 30302-4010, USA.,Department of Chemistry, College of Arts and Sciences, Georgia State University, Atlanta, GA, 30302-3965, USA.,Center for Biotechnology and Drug Design, Georgia State University, Atlanta, GA, 30303, USA.,Center for Diagnostics and Therapeutics, Georgia State University, Atlanta, GA, 30303, USA
| | - Zehava Eichenbaum
- Department of Biology, College of Arts and Sciences, Georgia State University, P.O. Box 4010, Atlanta, GA, 30302-4010, USA.
| |
Collapse
|
29
|
Unique coupling of mono- and dioxygenase chemistries in a single active site promotes heme degradation. Proc Natl Acad Sci U S A 2016; 113:3779-84. [PMID: 27006503 DOI: 10.1073/pnas.1523333113] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Bacterial pathogens must acquire host iron for survival and colonization. Because free iron is restricted in the host, numerous pathogens have evolved to overcome this limitation by using a family of monooxygenases that mediate the oxidative cleavage of heme into biliverdin, carbon monoxide, and iron. However, the etiological agent of tuberculosis, Mycobacterium tuberculosis, accomplishes this task without generating carbon monoxide, which potentially induces its latent state. Here we show that this unusual heme degradation reaction proceeds through sequential mono- and dioxygenation events within the single active center of MhuD, a mechanism unparalleled in enzyme catalysis. A key intermediate of the MhuD reaction is found to be meso-hydroxyheme, which reacts with O2 at an unusual position to completely suppress its monooxygenation but to allow ring cleavage through dioxygenation. This mechanistic change, possibly due to heavy steric deformation of hydroxyheme, rationally explains the unique heme catabolites of MhuD. Coexistence of mechanistically distinct functions is a previously unidentified strategy to expand the physiological outcome of enzymes, and may be applied to engineer unique biocatalysts.
Collapse
|
30
|
HmuS and HmuQ of Ensifer/Sinorhizobium meliloti degrade heme in vitro and participate in heme metabolism in vivo. Biometals 2016; 29:333-47. [DOI: 10.1007/s10534-016-9919-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2016] [Accepted: 02/19/2016] [Indexed: 12/20/2022]
|
31
|
Ouellet YH, Ndiaye CT, Gagné SM, Sebilo A, Suits MD, Jubinville É, Jia Z, Ivancich A, Couture M. An alternative reaction for heme degradation catalyzed by the Escherichia coli O157:H7 ChuS protein: Release of hematinic acid, tripyrrole and Fe(III). J Inorg Biochem 2016; 154:103-13. [DOI: 10.1016/j.jinorgbio.2015.11.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2015] [Revised: 10/08/2015] [Accepted: 11/01/2015] [Indexed: 11/24/2022]
|
32
|
Hogle SL, Barbeau KA, Gledhill M. Heme in the marine environment: from cells to the iron cycle. Metallomics 2015; 6:1107-20. [PMID: 24811388 DOI: 10.1039/c4mt00031e] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Hemes are iron containing heterocyclic molecules important in many cellular processes. In the marine environment, hemes participate as enzymatic cofactors in biogeochemically significant processes like photosynthesis, respiration, and nitrate assimilation. Further, hemoproteins, hemes, and their analogs appear to be iron sources for some marine bacterioplankton under certain conditions. Current oceanographic analytical methodologies allow for the extraction and measurement of heme b from marine material, and a handful of studies have begun to examine the distribution of heme b in ocean basins. The study of heme in the marine environment is still in its infancy, but some trends can be gleaned from the work that has been published so far. In this review, we summarize what is known or might be inferred about the roles of heme in marine microbes as well as the few studies on heme in the marine environment that have been conducted to date. We conclude by presenting some future questions and challenges for the field.
Collapse
Affiliation(s)
- Shane L Hogle
- Geoscience Research Division, Scripps Institution of Oceanography, La Jolla, California, USA.
| | | | | |
Collapse
|
33
|
Wilks A, Ikeda-Saito M. Heme utilization by pathogenic bacteria: not all pathways lead to biliverdin. Acc Chem Res 2014; 47:2291-8. [PMID: 24873177 PMCID: PMC4139177 DOI: 10.1021/ar500028n] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
![]()
The eukaryotic heme oxygenases (HOs) (E.C. 1.14.99.3) convert heme
to biliverdin, iron, and carbon monoxide (CO) in three successive
oxygenation steps. Pathogenic bacteria require iron for survival and
infection. Extracellular heme uptake from the host plays a critical
role in iron acquisition and virulence. In the past decade, several
HOs required for the release of iron from extracellular heme have
been identified in pathogenic bacteria, including Corynebacterium
diphtheriae, Neisseriae meningitides, and Pseudomonas aeruginosa. The
bacterial enzymes were shown to be structurally and mechanistically
similar to those of the canonical eukaryotic HO enzymes. However,
the recent discovery of the structurally and mechanistically distinct
noncanonical heme oxygenases of Staphylococcus aureus and Mycobacterium tuberculosis has
expanded the reaction manifold of heme degradation. The distinct ferredoxin-like
structural fold and extreme heme ruffling are proposed to give rise
to the alternate heme degradation products in the S.
aureus and M. tuberculosis enzymes. In addition, several “heme-degrading factors”
with no structural homology to either class of HOs have recently been
reported. The identification of these “heme-degrading proteins”
has largely been determined on the basis of in vitro heme degradation
assays. Many of these proteins were reported to produce biliverdin,
although no extensive characterization of the products was performed.
Prior to the characterization of the canonical HO enzymes, the nonenzymatic
degradation of heme and heme proteins in the presence of a reductant
such as ascorbate or hydrazine, a reaction termed “coupled
oxidation”, served as a model for biological heme degradation.
However, it was recognized that there were important mechanistic differences
between the so-called coupled oxidation of heme proteins and enzymatic
heme oxygenation. In the coupled oxidation reaction, the final product,
verdoheme, can readily be converted to biliverdin under hydrolytic
conditions. The differences between heme oxygenation by the canonical
and noncanonical HOs and coupled oxidation will be discussed in the
context of the stabilization of the reactive FeIII–OOH
intermediate and regioselective heme hydroxylation. Thus, in the determination
of heme oxygenase activity in vitro, it is important to ensure that
the reaction proceeds through successive oxygenation steps. We further
suggest that when bacterial heme degradation is being characterized,
a systems biology approach combining genetics, mechanistic enzymology,
and metabolite profiling should be undertaken.
Collapse
Affiliation(s)
- Angela Wilks
- Department
of Pharmaceutical Sciences, University of Maryland, Baltimore, Maryland 21201-1140, United States
| | - Masao Ikeda-Saito
- Institute
of Multidisciplinary Research for Advanced Materials, Tohoku University Katahira, Aoba, Sendai 980-8577, Japan
| |
Collapse
|
34
|
Lee MJ, Schep D, McLaughlin B, Kaufmann M, Jia Z. Structural Analysis and Identification of PhuS as a Heme-Degrading Enzyme from Pseudomonas aeruginosa. J Mol Biol 2014; 426:1936-46. [DOI: 10.1016/j.jmb.2014.02.013] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2014] [Revised: 02/13/2014] [Accepted: 02/14/2014] [Indexed: 10/25/2022]
|
35
|
Duong T, Park K, Kim T, Kang SW, Hahn MJ, Hwang HY, Kim KK. Structural and functional characterization of an Isd-type haem-degradation enzyme fromListeria monocytogenes. ACTA ACUST UNITED AC 2014; 70:615-26. [DOI: 10.1107/s1399004713030794] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2013] [Accepted: 11/08/2013] [Indexed: 11/10/2022]
Abstract
Bacterial pathogens have evolved diverse types of efficient machinery to acquire haem, the most abundant source of iron in the human body, and degrade it for the utilization of iron. Gram-positive bacteria commonly encode IsdG-family proteins as haem-degrading monooxygenases.Listeria monocytogenesis predicted to possess an IsdG-type protein (Lmo2213), but the residues involved in haem monooxygenase activity are not well conserved and there is an extra N-terminal domain in Lmo2213. Therefore, its function and mechanism of action cannot be predicted. In this study, the crystal structure of Lmo2213 was determined at 1.75 Å resolution and its haem-binding and haem-degradation activities were confirmed. Structure-based mutational and functional assays of this protein, designated as an Isd-typeL. monocytogeneshaem-degrading enzyme (Isd-LmHde), identified that Glu71, Tyr87 and Trp129 play important roles in haem degradation and that the N-terminal domain is also critical for its haem-degrading activity. The haem-degradation product of Isd-LmHde is verified to be biliverdin, which is also known to be the degradation product of other bacterial haem oxygenases. This study, the first structural and functional report of the haem-degradation system inL. monocytogenes, sheds light on the concealed haem-utilization system in this life-threatening human pathogen.
Collapse
|
36
|
Crystal structure of the Pseudomonas aeruginosa cytoplasmic heme binding protein, Apo-PhuS. J Inorg Biochem 2013; 128:131-6. [PMID: 23973453 PMCID: PMC3843485 DOI: 10.1016/j.jinorgbio.2013.07.030] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2013] [Revised: 07/19/2013] [Accepted: 07/21/2013] [Indexed: 01/07/2023]
Abstract
Iron is an essential element to all living organisms and is an important determinant of bacterial virulence. Bacteria have evolved specialized systems to sequester and transport iron from the environment or host. Pseudomonas aeruginosa, an opportunistic pathogen, uses two outer membrane receptor mediated systems (Phu and Has) to utilize host heme as a source of iron. PhuS is a 39 kDa soluble cytoplasmic heme binding protein which interacts and transports heme from the inner membrane heme transporter to the cytoplasm where it is degraded by heme oxygenase thus releasing iron. PhuS is unique among other cytoplasmic heme transporter proteins owing to the presence of three histidines in the heme binding pocket which can potentially serve as heme ligands. Out of the three histidine residues on the heme binding helix, His 209 is conserved among heme trafficking proteins while His 210 and His 212 are unique to PhuS. Here we report the crystal structure of PhuS at 1.98Å resolution which shows a unique heme binding pocket and oligomeric structure compared to other known cytoplasmic heme transporter and accounts for some of the unusual biochemical properties of PhuS.
Collapse
|
37
|
Runyen-Janecky LJ. Role and regulation of heme iron acquisition in gram-negative pathogens. Front Cell Infect Microbiol 2013; 3:55. [PMID: 24116354 PMCID: PMC3792355 DOI: 10.3389/fcimb.2013.00055] [Citation(s) in RCA: 88] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2013] [Accepted: 09/10/2013] [Indexed: 12/14/2022] Open
Abstract
Bacteria that reside in animal tissues and/or cells must acquire iron from their host. However, almost all of the host iron is sequestered in iron-containing compounds and proteins, the majority of which is found within heme molecules. Thus, likely iron sources for bacterial pathogens (and non-pathogenic symbionts) are free heme and heme-containing proteins. Furthermore, the cellular location of the bacterial within the host (intra or extracellular) influences the amount and nature of the iron containing compounds available for transport. The low level of free iron in the host, coupled with the presence of numerous different heme sources, has resulted in a wide range of high-affinity iron acquisition strategies within bacteria. However, since excess iron and heme are toxic to bacteria, expression of these acquisition systems is highly regulated. Precise expression in the correct host environment at the appropriate times enables heme iron acquisitions systems to contribute to the growth of bacterial pathogens within the host. This mini-review will highlight some of the recent findings in these areas for gram-negative pathogens.
Collapse
|
38
|
Abstract
The proliferative capability of many invasive pathogens is limited by the bioavailability of iron. Pathogens have thus developed strategies to obtain iron from their host organisms. In turn, host defense strategies have evolved to sequester iron from invasive pathogens. This review explores the mechanisms employed by bacterial pathogens to gain access to host iron sources, the role of iron in bacterial virulence, and iron-related genes required for the establishment or maintenance of infection. Host defenses to limit iron availability for bacterial growth during the acute-phase response and the consequences of iron overload conditions on susceptibility to bacterial infection are also examined. The evidence summarized herein demonstrates the importance of iron bioavailability in influencing the risk of infection and the ability of the host to clear the pathogen.
Collapse
|
39
|
Abstract
All but a few bacterial species have an absolute need for heme, and most are able to synthesize it via a pathway that is highly conserved among all life domains. Because heme is a rich source for iron, many pathogenic bacteria have also evolved processes for sequestering heme from their hosts. The heme biosynthesis pathways are well understood at the genetic and structural biology levels. In comparison, much less is known about the heme acquisition, trafficking, and degradation processes in bacteria. Gram-positive and Gram-negative bacteria have evolved similar strategies but different tactics for importing and degrading heme, likely as a consequence of their different cellular architectures. The differences are manifested in distinct structures for molecules that perform similar functions. Consequently, the aim of this chapter is to provide an overview of the structural biology of proteins and protein-protein interactions that enable Gram-positive and Gram-negative bacteria to sequester heme from the extracellular milieu, import it to the cytosol, and degrade it to mine iron.
Collapse
Affiliation(s)
- David R Benson
- Department of Chemistry, University of Kansas, Multidisciplinary Research Building, 2030 Becker Dr., Lawrence, KS, 66047, USA,
| | | |
Collapse
|
40
|
Liu X, Gong J, Wei T, Wang Z, Du Q, Zhu D, Huang Y, Xu S, Gu L. Crystal structure of HutZ, a heme storage protein from Vibrio cholerae: A structural mismatch observed in the region of high sequence conservation. BMC STRUCTURAL BIOLOGY 2012; 12:23. [PMID: 23013214 PMCID: PMC3472187 DOI: 10.1186/1472-6807-12-23] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/15/2012] [Accepted: 09/24/2012] [Indexed: 01/03/2023]
Abstract
Background HutZ is the sole heme storage protein identified in the pathogenic bacterium Vibrio cholerae and is required for optimal heme utilization. However, no heme oxygenase activity has been observed with this protein. Thus far, HutZ’s structure and heme-binding mechanism are unknown. Results We report the first crystal structure of HutZ in a homodimer determined at 2.0 Å resolution. The HutZ structure adopted a typical split-barrel fold. Through a docking study and site-directed mutagenesis, a heme-binding model for the HutZ dimer is proposed. Very interestingly, structural superimposition of HutZ and its homologous protein HugZ, a heme oxygenase from Helicobacter pylori, exhibited a structural mismatch of one amino acid residue in β6 of HutZ, although residues involved in this region are highly conserved in both proteins. Derived homologous models of different single point variants with model evaluations suggested that Pro140 of HutZ, corresponding to Phe215 of HugZ, might have been the main contributor to the structural mismatch. This mismatch initiates more divergent structural characteristics towards their C-terminal regions, which are essential features for the heme-binding of HugZ as a heme oxygenase. Conclusions HutZ’s deficiency in heme oxygenase activity might derive from its residue shift relative to the heme oxygenase HugZ. This residue shift also emphasized a limitation of the traditional template selection criterion for homology modeling.
Collapse
Affiliation(s)
- Xiuhua Liu
- State Key Laboratory of Microbial Technology, School of Life Sciences, Shandong University, Jinan, 250100, China
| | | | | | | | | | | | | | | | | |
Collapse
|
41
|
Sigala PA, Crowley JR, Hsieh S, Henderson JP, Goldberg DE. Direct tests of enzymatic heme degradation by the malaria parasite Plasmodium falciparum. J Biol Chem 2012; 287:37793-807. [PMID: 22992734 PMCID: PMC3488054 DOI: 10.1074/jbc.m112.414078] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Malaria parasites generate vast quantities of heme during blood stage infection via hemoglobin digestion and limited de novo biosynthesis, but it remains unclear if parasites metabolize heme for utilization or disposal. Recent in vitro experiments with a heme oxygenase (HO)-like protein from Plasmodium falciparum suggested that parasites may enzymatically degrade some heme to the canonical HO product, biliverdin (BV), or its downstream metabolite, bilirubin (BR). To directly test for BV and BR production by P. falciparum parasites, we DMSO-extracted equal numbers of infected and uninfected erythrocytes and developed a sensitive LC-MS/MS assay to quantify these tetrapyrroles. We found comparable low levels of BV and BR in both samples, suggesting the absence of HO activity in parasites. We further tested live parasites by targeted expression of a fluorescent BV-binding protein within the parasite cytosol, mitochondrion, and plant-like plastid. This probe could detect exogenously added BV but gave no signal indicative of endogenous BV production within parasites. Finally, we recombinantly expressed and tested the proposed heme degrading activity of the HO-like protein, PfHO. Although PfHO bound heme and protoporphyrin IX with modest affinity, it did not catalyze heme degradation in vivo within bacteria or in vitro in UV absorbance and HPLC assays. These observations are consistent with PfHO's lack of a heme-coordinating His residue and suggest an alternative function within parasites. We conclude that P. falciparum parasites lack a canonical HO pathway for heme degradation and thus rely fully on alternative mechanisms for heme detoxification and iron acquisition during blood stage infection.
Collapse
Affiliation(s)
- Paul A Sigala
- Department of Molecular Microbiology and the Howard Hughes Medical Institute, Washington University School of Medicine, St. Louis, Missouri 63110, USA
| | | | | | | | | |
Collapse
|
42
|
Juárez-Verdayes MA, González-Uribe PM, Peralta H, Rodríguez-Martínez S, Jan-Roblero J, Escamilla-Hernández R, Cancino-Diaz ME, Cancino-Diaz JC. Detection of hssS, hssR, hrtA, and hrtB genes and their expression by hemin in Staphylococcus epidermidis. Can J Microbiol 2012; 58:1063-72. [DOI: 10.1139/w2012-086] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Staphylococcus aureus employs a heme sensing system (HssR–HssS) and a heme-regulated transporter efflux pump (HrtA–HrtB) to avoid the accumulation of heme, which is toxic at high concentrations. The detoxification system to heme has not been studied in Staphylococcus epidermidis . In this work, the hssR, hssS, hrtA, and hrtB genes were detected, and their expression when stimulated by hemin in S. epidermidis was explored. In silico genomic analyses exhibited that the genetic organization of the hssRS and hrtAB genes was identical in 11 Staphylococcus species analyzed, including S. epidermidis. Slight variations were found in their syntenic regions. The predicted secondary structure of HrtAB proteins from these species was almost identical to these of S. aureus. Additionally, hrtAB promoter sequences of some species were analyzed, and 1 or 2 different nucleotide substitutions were found in the downstream motif. Concentrations of hemin above 5 µmol/L inhibited S. epidermidis growth. However, S. epidermidis that was pre-exposed to a subinhibitory hemin concentration (1 µmol/L) was able to grow when inoculated into medium containing above 5 µmol/L hemin. The expression levels of hrtA and hrtB genes in S. epidermidis exhibited a significant difference when they were stimulated with hemin. Our results suggest that the HrtAB could be involved in hemin detoxification of S. epidermidis.
Collapse
Affiliation(s)
| | | | - Humberto Peralta
- Functional Genomics of Prokaryotes Program, Centro de Ciencias Genómicas, Universidad Autónoma de México, Cuernavaca, Mor. Mexico
| | | | - Janet Jan-Roblero
- Microbiology Department, Escuela Nacional de Ciencias Biológicas-IPN, Mexico City, Mexico
| | | | - Mario E. Cancino-Diaz
- Immunology Department, Escuela Nacional de Ciencias Biológicas-IPN, Mexico City, Mexico
| | - Juan C. Cancino-Diaz
- Microbiology Department, Escuela Nacional de Ciencias Biológicas-IPN, Mexico City, Mexico
| |
Collapse
|
43
|
Tavares AFN, Nobre LS, Saraiva LM. A role for reactive oxygen species in the antibacterial properties of carbon monoxide-releasing molecules. FEMS Microbiol Lett 2012; 336:1-10. [PMID: 22774863 DOI: 10.1111/j.1574-6968.2012.02633.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2012] [Revised: 07/02/2012] [Accepted: 07/03/2012] [Indexed: 12/24/2022] Open
Abstract
Carbon monoxide-releasing molecules (CO-RMs) are, in general, transition metal carbonyl complexes that liberate controlled amounts of CO. In animal models, CO-RMs have been shown to reduce myocardial ischaemia, inflammation and vascular dysfunction, and to provide a protective effect in organ transplantation. Moreover, CO-RMs are bactericides that kill both Gram-positive and Gram-negative bacteria such as Staphylococcus aureus and Pseudomonas aeruginosa. Herein are reviewed the microbial genetic and biochemical responses associated with CO-RM-mediated cell death. Particular emphasis is given to the data revealing that CO-RMs induce the generation of reactive oxygen species (ROS), which contribute to the antibacterial activity of these compounds.
Collapse
Affiliation(s)
- Ana Filipa N Tavares
- Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa, Oeiras, Portugal
| | | | | |
Collapse
|
44
|
Liu M, Boulouis HJ, Biville F. Heme degrading protein HemS is involved in oxidative stress response of Bartonella henselae. PLoS One 2012; 7:e37630. [PMID: 22701524 PMCID: PMC3365110 DOI: 10.1371/journal.pone.0037630] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2012] [Accepted: 04/26/2012] [Indexed: 01/24/2023] Open
Abstract
Bartonellae are hemotropic bacteria, agents of emerging zoonoses. These bacteria are heme auxotroph Alphaproteobacteria which must import heme for supporting their growth, as they cannot synthesize it. Therefore, Bartonella genome encodes for a complete heme uptake system allowing the transportation of this compound across the outer membrane, the periplasm and the inner membranes. Heme has been proposed to be used as an iron source for Bartonella since these bacteria do not synthesize a complete system required for iron Fe3+uptake. Similarly to other bacteria which use heme as an iron source, Bartonellae must transport this compound into the cytoplasm and degrade it to allow the release of iron from the tetrapyrrole ring. For Bartonella, the gene cluster devoted to the synthesis of the complete heme uptake system also contains a gene encoding for a polypeptide that shares homologies with heme trafficking or degrading enzymes. Using complementation of an E. coli mutant strain impaired in heme degradation, we demonstrated that HemS from Bartonella henselae expressed in E. coli allows the release of iron from heme. Purified HemS from B. henselae binds heme and can degrade it in the presence of a suitable electron donor, ascorbate or NADPH-cytochrome P450 reductase. Knocking down the expression of HemS in B. henselae reduces its ability to face H2O2 induced oxidative stress.
Collapse
Affiliation(s)
- MaFeng Liu
- Université Paris-Est, Ecole nationale vétérinaire d'Alfort, UMR BIPAR INRA-Anses-UPEC-ENVA, Maisons-Alfort, France
- Key Laboratory of Zoonosis, Ministry of Education, Institute of Zoonosis, Jilin University, Changchun, People's Republic of China
| | - Henri-Jean Boulouis
- Université Paris-Est, Ecole nationale vétérinaire d'Alfort, UMR BIPAR INRA-Anses-UPEC-ENVA, Maisons-Alfort, France
| | - Francis Biville
- Université Paris-Est, Ecole nationale vétérinaire d'Alfort, UMR BIPAR INRA-Anses-UPEC-ENVA, Maisons-Alfort, France
- Département de Microbiologie, Pasteur Institute, Paris, France
- * E-mail:
| |
Collapse
|
45
|
Barker KD, Barkovits K, Wilks A. Metabolic flux of extracellular heme uptake in Pseudomonas aeruginosa is driven by the iron-regulated heme oxygenase (HemO). J Biol Chem 2012; 287:18342-50. [PMID: 22493498 DOI: 10.1074/jbc.m112.359265] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Heme utilization by Pseudomonas aeruginosa involves several proteins required for internalization and degradation of heme. In the following report we provide the first direct in vivo evidence for the specific degradation of extracellular heme to biliverdin (BV) by the iron-regulated HemO. Moreover, through isotopic labeling ((13)C-heme) and electrospray ionization-MS analysis we have confirmed the regioselectivity and ratio of (13)C-δ and β-BV IX (70:30) is identical in vivo to that previously observed for the purified protein. Furthermore, the (13)C-BV IXδ and BV IXβ products are effluxed from the cell by an as yet unidentified transporter. Conversion of extracellular heme to BV is dependent solely on the iron-regulated HemO as evidenced by the lack of BV production in the P. aeruginosa hemO deletion strain. Complementation of P. aeruginosa ΔhemO with a plasmid expressing either the wild type HemO or α-regioselective HemO mutant restored extracellular heme uptake and degradation. In contrast deletion of the gene encoding the cytoplasmic heme-binding protein, PhuS, homologs of which have been proposed to be heme oxygenases, did not eliminate (13)C-BV IXδ and IXβ production. In conclusion the metabolic flux of extracellular heme as a source of iron is driven by the catalytic action of HemO.
Collapse
Affiliation(s)
- Kylie D Barker
- Department of Pharmaceutical Sciences, School of Pharmacy, University of Maryland, Baltimore, Maryland 21201-1140, USA
| | | | | |
Collapse
|
46
|
Induced fit on heme binding to the Pseudomonas aeruginosa cytoplasmic protein (PhuS) drives interaction with heme oxygenase (HemO). Proc Natl Acad Sci U S A 2012; 109:5639-44. [PMID: 22451925 DOI: 10.1073/pnas.1121549109] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Iron, an essential nutrient with limited bioavailability, requires specialized cellular mechanisms for uptake. Although iron uptake into the cytoplasm in the form of heme has been well characterized in many bacteria, the subsequent trafficking is poorly understood. The cytoplasmic heme-binding proteins belong to a structurally related family thought to have evolved as "induced fit" ligand-binding macromolecules. One member, Pseudomonas aeruginosa cytoplasmic protein (PhuS), has previously been shown to be important for delivering heme to the iron regulated heme oxygenase (HemO). Spectroscopic investigations of the holo-PhuS complex revealed a dynamic heme environment with overlapping but distinct heme-binding sites with alternative coordinating heme ligands, His-209 or His-212. In the present work we establish a mechanism for how heme is transferred from PhuS to its partner, HemO. Using surface plasmon resonance and isothermal titration calorimetry, we have discovered that holo-PhuS, but not apo-PhuS, forms a 1:1 complex with HemO. Sedimentation velocity and limited proteolysis experiments suggest that heme binding to PhuS induces a conformational rearrangement that drives the protein interaction with HemO. Hydrodynamic analysis reveals that the holo-PhuS displays a more expanded hydrodynamic envelope compared with apo-PhuS, and we propose that this conformational change drives the interaction with HemO. We further demonstrate that replacement of His-212 by Ala disrupts the interaction of holo-PhuS with HemO; in contrast, the His-209-Ala variant can still complex with HemO, albeit more weakly. Together, the present studies reveal a mechanism that couples a heme-dependent conformational switch in PhuS to protein-protein interaction, the subsequent free energy of which drives heme release to HemO.
Collapse
|
47
|
Smith AD, Wilks A. Extracellular heme uptake and the challenges of bacterial cell membranes. CURRENT TOPICS IN MEMBRANES 2012; 69:359-92. [PMID: 23046657 PMCID: PMC3731948 DOI: 10.1016/b978-0-12-394390-3.00013-6] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
In bacteria, the fine balance of maintaining adequate iron levels while preventing the deleterious effects of excess iron has led to the evolution of sophisticated cellular mechanisms to obtain, store, and regulate iron. Iron uptake provides a significant challenge given its limited bioavailability and need to be transported across the bacterial cell wall and membranes. Pathogenic bacteria have circumvented the iron-availability issue by utilizing the hosts' heme-containing proteins as a source of iron. Once internalized, iron is liberated from the porphyrin enzymatically for cellular processes within the bacterial cell. Heme, a lipophilic and toxic molecule, poses a significant challenge in terms of transport given its chemical reactivity. As such, pathogenic bacteria have evolved sophisticated membrane transporters to coordinate, sequester, and transport heme. Recent advances in the biochemical and structural characterization of the membrane-bound heme transport proteins are discussed in the context of ligand coordination, protein-protein interaction, and heme transfer.
Collapse
Affiliation(s)
- Aaron D. Smith
- Department of Pharmaceutical Sciences, School of Pharmacy, University of Maryland, Baltimore, USA
| | - Angela Wilks
- Department of Pharmaceutical Sciences, School of Pharmacy, University of Maryland, Baltimore, USA
| |
Collapse
|
48
|
Hopkinson BM, Barbeau KA. Iron transporters in marine prokaryotic genomes and metagenomes. Environ Microbiol 2011; 14:114-28. [DOI: 10.1111/j.1462-2920.2011.02539.x] [Citation(s) in RCA: 78] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
49
|
Overcoming the heme paradox: heme toxicity and tolerance in bacterial pathogens. Infect Immun 2010; 78:4977-89. [PMID: 20679437 DOI: 10.1128/iai.00613-10] [Citation(s) in RCA: 208] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Virtually all bacterial pathogens require iron to infect vertebrates. The most abundant source of iron within vertebrates is in the form of heme as a cofactor of hemoproteins. Many bacterial pathogens have elegant systems dedicated to the acquisition of heme from host hemoproteins. Once internalized, heme is either degraded to release free iron or used intact as a cofactor in catalases, cytochromes, and other bacterial hemoproteins. Paradoxically, the high redox potential of heme makes it a liability, as heme is toxic at high concentrations. Although a variety of mechanisms have been proposed to explain heme toxicity, the mechanisms by which heme kills bacteria are not well understood. Nonetheless, bacteria employ various strategies to protect against and eliminate heme toxicity. Factors involved in heme acquisition and detoxification have been found to contribute to virulence, underscoring the physiological relevance of heme stress during pathogenesis. Herein we describe the current understanding of the mechanisms of heme toxicity and how bacterial pathogens overcome the heme paradox during infection.
Collapse
|
50
|
Carbon monoxide in biology and microbiology: surprising roles for the "Detroit perfume". Adv Microb Physiol 2009; 56:85-167. [PMID: 20943125 DOI: 10.1016/s0065-2911(09)05603-3] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Carbon monoxide (CO) is a colorless, odorless gas with a reputation for being an anthropogenic poison; there is extensive documentation of the modes of human exposure, toxicokinetics, and health effects. However, CO is also generated endogenously by heme oxygenases (HOs) in mammals and microbes, and its extraordinary biological activities are now recognized and increasingly utilized in medicine and physiology. This review introduces recent advances in CO biology and chemistry and illustrates the exciting possibilities that exist for a deeper understanding of its biological consequences. However, the microbiological literature is scant and is currently restricted to: 1) CO-metabolizing bacteria, CO oxidation by CO dehydrogenase (CODH) and the CO-sensing mechanisms that enable CO oxidation; 2) the use of CO as a heme ligand in microbial biochemistry; and 3) very limited information on how microbes respond to CO toxicity. We demonstrate how our horizons in CO biology have been extended by intense research activity in recent years in mammalian and human physiology and biochemistry. CO is one of several "new" small gas molecules that are increasingly recognized for their profound and often beneficial biological activities, the others being nitric oxide (NO) and hydrogen sulfide (H2S). The chemistry of CO and other heme ligands (oxygen, NO, H2S and cyanide) and the implications for biological interactions are briefly presented. An important advance in recent years has been the development of CO-releasing molecules (CO-RMs) for aiding experimental administration of CO as an alternative to the use of CO gas. The chemical principles of CO-RM design and mechanisms of CO release from CO-RMs (dissociation, association, reduction and oxidation, photolysis, and acidification) are reviewed and we present a survey of the most commonly used CO-RMs. Amongst the most important new applications of CO in mammalian physiology and medicine are its vasoactive properties and the therapeutic potentials of CO-RMs in vascular disease, anti-inflammatory effects, CO-mediated cell signaling in apoptosis, applications in organ preservation, and the effects of CO on mitochondrial function. The very limited literature on microbial growth responses to CO and CO-RMs in vitro, and the transcriptomic and physiological consequences of microbial exposure to CO and CO-RMs are reviewed. There is current interest in CO and CO-RMs as antimicrobial agents, particularly in the control of bacterial infections. Future prospects are suggested and unanswered questions posed.
Collapse
|