1
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Kronborg K, Zhang YE. cAMP competitively inhibits periplasmic phosphatases to coordinate nutritional growth with competence of Haemophilus influenzae. J Biol Chem 2023; 299:105404. [PMID: 38229398 PMCID: PMC10694654 DOI: 10.1016/j.jbc.2023.105404] [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: 05/30/2023] [Revised: 10/17/2023] [Accepted: 10/19/2023] [Indexed: 01/18/2024] Open
Abstract
Most naturally competent bacteria tightly regulate the window of the competent state to maximize their ecological fitness under specific conditions. Development of competence by Haemophilus influenzae strain Rd KW20 is stimulated by cAMP and inhibited by purine nucleotides, respectively. In contrast, cAMP inhibits cell growth, but nucleotides are important for KW20 growth. However, the mechanisms underlying the abovementioned reciprocal effects are unclear. Here, we first identified a periplasmic acid phosphatase AphAEc of Escherichia coli as a new cAMP-binding protein. We show cAMP competitively inhibits the phosphatase activities of AphAEc and its homolog protein AphAHi in the KW20 strain. Furthermore, we found cAMP inhibits two other periplasmic nonspecific phosphatases, NadNHi (which provides the essential growth factor V, NAD) and HelHi (eP4, which converts NADP to NAD) in KW20. We demonstrate cAMP inhibits cell growth rate, especially via NadNHi. On the other hand, the inhibitory effect of purine nucleotide AMP on competence was abolished in the triple deletion mutant ΔhelHiΔnadNHiΔaphAHi, but not in the single, double deletion or complemented strains. Adenosine, however, still inhibited the competence of the triple deletion mutant, demonstrating the crucial role of the three phosphatases in converting nucleotides to nucleosides and thus inhibiting KW20 competence. Finally, cAMP restored the competence inhibited by GMP in a dose-dependent manner, but not competence inhibited by guanosine. Altogether, we uncovered these three periplasmic phosphatases as the key players underlying the antagonistic effects of cAMP and purine nucleotides on both cell growth and competence development of H. influenzae.
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Affiliation(s)
- Kristina Kronborg
- Department of Biology, University of Copenhagen, Copenhagen, Denmark
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2
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Dowling J, Doig CL. Roles of ADP-Ribosylation during Infection Establishment by Trypanosomatidae Parasites. Pathogens 2023; 12:pathogens12050708. [PMID: 37242378 DOI: 10.3390/pathogens12050708] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Revised: 05/08/2023] [Accepted: 05/09/2023] [Indexed: 05/28/2023] Open
Abstract
ADP-ribosylation is a reversible post-translational protein modification, which is evolutionarily conserved in prokaryotic and eukaryotic organisms. It governs critical cellular functions, including, but not limited to cellular proliferation, differentiation, RNA translation, and genomic repair. The addition of one or multiple ADP-ribose moieties can be catalysed by poly(ADP-ribose) polymerase (PARP) enzymes, while in eukaryotic organisms, ADP-ribosylation can be reversed through the action of specific enzymes capable of ADP-ribose signalling regulation. In several lower eukaryotic organisms, including Trypanosomatidae parasites, ADP-ribosylation is thought to be important for infection establishment. Trypanosomatidae encompasses several human disease-causing pathogens, including Trypanosoma cruzi, T. brucei, and the Leishmania genus. These parasites are the etiological agents of Chagas disease, African trypanosomiasis (sleeping sickness), and leishmaniasis, respectively. Currently, licenced medications for these infections are outdated and often result in harmful side effects, and can be inaccessible to those carrying infections, due to them being classified as neglected tropical diseases (NTDs), meaning that many infected individuals will belong to already marginalised communities in countries already facing socioeconomic challenges. Consequently, funding to develop novel therapeutics for these infections is overlooked. As such, understanding the molecular mechanisms of infection, and how ADP-ribosylation facilitates infection establishment by these organisms may allow the identification of potential molecular interventions that would disrupt infection. In contrast to the complex ADP-ribosylation pathways in eukaryotes, the process of Trypanosomatidae is more linear, with the parasites only expressing one PARP enzyme, compared to the, at least, 17 genes that encode human PARP enzymes. If this simplified pathway can be understood and exploited, it may reveal new avenues for combatting Trypanosomatidae infection. This review will focus on the current state of knowledge on the importance of ADP-ribosylation in Trypanosomatidae during infection establishment in human hosts, and the potential therapeutic options that disrupting ADP-ribosylation may offer to combat Trypanosomatidae.
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Affiliation(s)
- Joshua Dowling
- School of Science & Technology, Nottingham Trent University, Nottingham NG11 8NS, UK
| | - Craig L Doig
- School of Science & Technology, Nottingham Trent University, Nottingham NG11 8NS, UK
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3
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Lee H, Edgar RJ, Lichtenstein IJ, Velarde JJ, Korotkova N, Wessels MR. Streptococcus pyogenes can support or inhibit growth of Haemophilus influenzae by supplying or restricting extracellular NAD+. PLoS One 2022; 17:e0270697. [PMID: 36170255 PMCID: PMC9518897 DOI: 10.1371/journal.pone.0270697] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Accepted: 06/15/2022] [Indexed: 11/19/2022] Open
Abstract
Nicotinamide adenine dinucleotide (NAD+) is an essential co-factor for cellular metabolism and serves as a substrate in enzymatic processes. NAD+ is produced by de novo synthesis or salvage pathways in nearly all bacterial species. Haemophilus influenzae lacks the capacity for de novo synthesis, so it is dependent on import of NAD+ from the external environment or salvage biosynthetic pathways for recycling of NAD+ precursors and breakdown products. However, the actual sources of NAD+ utilized by H. influenzae in the respiratory tract are not well defined. In this study, we found that a variety of bacteria, including species found in the upper airway of humans, released NAD+ that was readily detectable in extracellular culture fluid, and which supported growth of H. influenzae in vitro. By contrast, certain strains of Streptococcus pyogenes (group A streptococcus or GAS) inhibited growth of H. influenzae in vitro by secreting NAD+-glycohydrolase (NADase), which degraded extracellular NAD+. Conversely, GAS strains that lacked enzymatically active NADase released extracellular NAD+, which could support H. influenzae growth. Our results suggest that many bacterial species, including normal flora of the upper airway, release NAD+ into the environment. GAS is distinctive in its ability to both release and degrade NAD+. Thus, colonization of the airway with H. influenzae may be promoted or restricted by co-colonization with GAS in a strain-specific manner that depends, respectively, on release of NAD+ or secretion of active NADase. We suggest that, in addition to its role as a cytotoxin for host cells, NADase may serve a separate function by restricting growth of H. influenzae in the human respiratory tract.
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Affiliation(s)
- Hyunju Lee
- Division of Infectious Diseases, Boston Children’s Hospital, Boston, Massachusetts, United States of America
- Department of Pediatrics, Harvard Medical School, Boston, Massachusetts, United States of America
- Department of Pediatrics, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seoul, Korea
| | - Rebecca J. Edgar
- Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, Kentucky, United States of America
| | - Ian J. Lichtenstein
- Division of Infectious Diseases, Boston Children’s Hospital, Boston, Massachusetts, United States of America
- Department of Pediatrics, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Jorge J. Velarde
- Division of Infectious Diseases, Boston Children’s Hospital, Boston, Massachusetts, United States of America
- Department of Pediatrics, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Natalia Korotkova
- Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, Kentucky, United States of America
- Department of Microbiology, Immunology and Molecular Genetics, University of Kentucky, Lexington, Kentucky, United States of America
| | - Michael R. Wessels
- Division of Infectious Diseases, Boston Children’s Hospital, Boston, Massachusetts, United States of America
- Department of Pediatrics, Harvard Medical School, Boston, Massachusetts, United States of America
- * E-mail:
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4
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Nasreen M, Nair RP, McEwan AG, Kappler U. The Peptide Methionine Sulfoxide Reductase (MsrAB) of Haemophilus influenzae Repairs Oxidatively Damaged Outer Membrane and Periplasmic Proteins Involved in Nutrient Acquisition and Virulence. Antioxidants (Basel) 2022; 11:antiox11081557. [PMID: 36009276 PMCID: PMC9404787 DOI: 10.3390/antiox11081557] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Revised: 08/06/2022] [Accepted: 08/08/2022] [Indexed: 11/16/2022] Open
Abstract
Sulfoxide-damage repair mechanisms are emerging as essential for the virulence of bacterial pathogens, and in the human respiratory pathogen Haemophilus influenzae the periplasmic MsrAB peptide methionine sulfoxide reductase is necessary for resistance to reactive chlorine species such as hypochlorite. Additionally, this enzyme has a role in modulating the host immune response to infection. Here, we have analysed the enzymatic properties of MsrAB, which revealed that both domains of the protein are catalytically active, with the turnover number of the MsrA domain being 50% greater than that for the MsrB domain. MsrAB was active with small molecular sulfoxides as well as oxidised calmodulin, and maximal activity was observed at 30°C, a temperature close to that found in the natural niche of H. influenzae, the nasopharynx. Analyses of differential methionine oxidation identified 29 outer membrane and periplasmic proteins that are likely substrates for MsrAB. These included the LldD lactate dehydrogenase and the lipoprotein eP4 that is involved in NAD and hemin metabolism in H. influenzae. Subsequent experiments showed that H. influenzae MsrAB can repair oxidative damage to methionines in purified eP4 with up to 100% efficiency. Our work links MsrAB to the maintenance of different adhesins and essential metabolic processes in the H. influenzae, such as NAD metabolism and access to L-lactate, which is a key growth substrate for H. influenzae during infection.
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5
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Metagenomic Insights into Pathogenic Characterization of ST410 Acinetobacter nosocomialis Prevalent in China. Pathogens 2022; 11:pathogens11080838. [PMID: 36014959 PMCID: PMC9414201 DOI: 10.3390/pathogens11080838] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2022] [Revised: 07/16/2022] [Accepted: 07/25/2022] [Indexed: 02/01/2023] Open
Abstract
Acinetobacter nosocomialis is a prevalent opportunistic pathogen that causes hospital-acquired infections. The increasing threats from A. nosocomialis infections have led to attention from the scientific and medical communities. Metagenomic next-generation sequencing (mNGS) was performed for an exudate specimen collected from an ICU patient with wound infection, followed by sepsis, in Tongji Hospital. Three assembly strategies were employed to recover the genome of A. nosocomialis in the metagenomic sample. Together with publicly available genomes of A. nosocomialis, the features of population genetics and molecular epidemiology were deeply analyzed. A draft genome was reconstructed for the metagenomic strain WHM01, derived from the ST410 A. nosocomialis dominating the microbial community, thereby prompting its highly pathogenic risk, which is associated with infection and persistence. The structure of the bacterial pangenome was characterized, including the 1862 core and 11,815 accessory genes present in the 157 strains. The genetic diversity of the genes coding for the 128 virulence factors assigned to 14 functional categories was uncovered in this nosocomial pathogen, such as the lipooligosaccharide, capsule, type IV pilus, and outer membrane proteins. Our work revealed genomic properties of ST410 A. nosocomialis, which is prevalent in China, and further highlighted that metagenomic surveillance may be a prospective application for evaluating the pathogenic characteristics of the nosocomial opportunistic pathogens.
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6
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Wilk A, Hayat F, Cunningham R, Li J, Garavaglia S, Zamani L, Ferraris DM, Sykora P, Andrews J, Clark J, Davis A, Chaloin L, Rizzi M, Migaud M, Sobol RW. Extracellular NAD + enhances PARP-dependent DNA repair capacity independently of CD73 activity. Sci Rep 2020; 10:651. [PMID: 31959836 PMCID: PMC6971268 DOI: 10.1038/s41598-020-57506-9] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2019] [Accepted: 12/29/2019] [Indexed: 02/06/2023] Open
Abstract
Changes in nicotinamide adenine dinucleotide (NAD+) levels that compromise mitochondrial function trigger release of DNA damaging reactive oxygen species. NAD+ levels also affect DNA repair capacity as NAD+ is a substrate for PARP-enzymes (mono/poly-ADP-ribosylation) and sirtuins (deacetylation). The ecto-5′-nucleotidase CD73, an ectoenzyme highly expressed in cancer, is suggested to regulate intracellular NAD+ levels by processing NAD+ and its bio-precursor, nicotinamide mononucleotide (NMN), from tumor microenvironments, thereby enhancing tumor DNA repair capacity and chemotherapy resistance. We therefore investigated whether expression of CD73 impacts intracellular NAD+ content and NAD+-dependent DNA repair capacity. Reduced intracellular NAD+ levels suppressed recruitment of the DNA repair protein XRCC1 to sites of genomic DNA damage and impacted the amount of accumulated DNA damage. Further, decreased NAD+ reduced the capacity to repair DNA damage induced by DNA alkylating agents. Overall, reversal of these outcomes through NAD+ or NMN supplementation was independent of CD73. In opposition to its proposed role in extracellular NAD+ bioprocessing, we found that recombinant human CD73 only poorly processes NMN but not NAD+. A positive correlation between CD73 expression and intracellular NAD+ content could not be made as CD73 knockout human cells were efficient in generating intracellular NAD+ when supplemented with NAD+ or NMN.
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Affiliation(s)
- Anna Wilk
- Mitchell Cancer Institute, University of South Alabama, Mobile, AL, 36604, USA.,Department of Pharmacology, College of Medicine, University of South Alabama, Mobile, AL, 36604, USA
| | - Faisal Hayat
- Mitchell Cancer Institute, University of South Alabama, Mobile, AL, 36604, USA.,Department of Pharmacology, College of Medicine, University of South Alabama, Mobile, AL, 36604, USA
| | - Richard Cunningham
- Mitchell Cancer Institute, University of South Alabama, Mobile, AL, 36604, USA.,Department of Pharmacology, College of Medicine, University of South Alabama, Mobile, AL, 36604, USA
| | - Jianfeng Li
- Mitchell Cancer Institute, University of South Alabama, Mobile, AL, 36604, USA.,Department of Pharmacology, College of Medicine, University of South Alabama, Mobile, AL, 36604, USA
| | - Silvia Garavaglia
- Department of Pharmaceutical Sciences, University of Piemonte Orientale, Largo Donegani 2, 28100, Novara, Italy
| | - Leila Zamani
- Mitchell Cancer Institute, University of South Alabama, Mobile, AL, 36604, USA
| | - Davide M Ferraris
- Department of Pharmaceutical Sciences, University of Piemonte Orientale, Largo Donegani 2, 28100, Novara, Italy
| | - Peter Sykora
- Mitchell Cancer Institute, University of South Alabama, Mobile, AL, 36604, USA.,Amelia Technologies, 14676 Rothgeb Drive, Rockville, MD, 20850, USA
| | - Joel Andrews
- Mitchell Cancer Institute, University of South Alabama, Mobile, AL, 36604, USA
| | - Jennifer Clark
- Mitchell Cancer Institute, University of South Alabama, Mobile, AL, 36604, USA.,Department of Pharmacology, College of Medicine, University of South Alabama, Mobile, AL, 36604, USA
| | - Amanda Davis
- Mitchell Cancer Institute, University of South Alabama, Mobile, AL, 36604, USA
| | - Laurent Chaloin
- Institut de Recherche en Infectiologie de Montpellier (IRIM), Université de Montpellier, CNRS, 34293, Montpellier, France
| | - Menico Rizzi
- Department of Pharmaceutical Sciences, University of Piemonte Orientale, Largo Donegani 2, 28100, Novara, Italy
| | - Marie Migaud
- Mitchell Cancer Institute, University of South Alabama, Mobile, AL, 36604, USA.,Department of Pharmacology, College of Medicine, University of South Alabama, Mobile, AL, 36604, USA
| | - Robert W Sobol
- Mitchell Cancer Institute, University of South Alabama, Mobile, AL, 36604, USA. .,Department of Pharmacology, College of Medicine, University of South Alabama, Mobile, AL, 36604, USA.
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7
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Vaca DJ, Thibau A, Schütz M, Kraiczy P, Happonen L, Malmström J, Kempf VAJ. Interaction with the host: the role of fibronectin and extracellular matrix proteins in the adhesion of Gram-negative bacteria. Med Microbiol Immunol 2019; 209:277-299. [PMID: 31784893 PMCID: PMC7248048 DOI: 10.1007/s00430-019-00644-3] [Citation(s) in RCA: 57] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2019] [Accepted: 11/14/2019] [Indexed: 01/03/2023]
Abstract
The capacity of pathogenic microorganisms to adhere to host cells and avoid clearance by the host immune system is the initial and most decisive step leading to infections. Bacteria have developed different strategies to attach to diverse host surface structures. One important strategy is the adhesion to extracellular matrix (ECM) proteins (e.g., collagen, fibronectin, laminin) that are highly abundant in connective tissue and basement membranes. Gram-negative bacteria express variable outer membrane proteins (adhesins) to attach to the host and to initiate the process of infection. Understanding the underlying molecular mechanisms of bacterial adhesion is a prerequisite for targeting this interaction by “anti-ligands” to prevent colonization or infection of the host. Future development of such “anti-ligands” (specifically interfering with bacteria-host matrix interactions) might result in the development of a new class of anti-infective drugs for the therapy of infections caused by multidrug-resistant Gram-negative bacteria. This review summarizes our current knowledge about the manifold interactions of adhesins expressed by Gram-negative bacteria with ECM proteins and the use of this information for the generation of novel therapeutic antivirulence strategies.
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Affiliation(s)
- Diana J Vaca
- Institute for Medical Microbiology and Infection Control, University Hospital, Goethe University Frankfurt am Main, Paul-Ehrlich-Str. 40, 60596, Frankfurt, Germany
| | - Arno Thibau
- Institute for Medical Microbiology and Infection Control, University Hospital, Goethe University Frankfurt am Main, Paul-Ehrlich-Str. 40, 60596, Frankfurt, Germany
| | - Monika Schütz
- Institute for Medical Microbiology and Infection Control, University Hospital, Eberhard Karls-University, Tübingen, Germany
| | - Peter Kraiczy
- Institute for Medical Microbiology and Infection Control, University Hospital, Goethe University Frankfurt am Main, Paul-Ehrlich-Str. 40, 60596, Frankfurt, Germany
| | - Lotta Happonen
- Division of Infection Medicine, Department of Clinical Sciences, Faculty of Medicine, Lund University, Lund, Sweden
| | - Johan Malmström
- Division of Infection Medicine, Department of Clinical Sciences, Faculty of Medicine, Lund University, Lund, Sweden
| | - Volkhard A J Kempf
- Institute for Medical Microbiology and Infection Control, University Hospital, Goethe University Frankfurt am Main, Paul-Ehrlich-Str. 40, 60596, Frankfurt, Germany.
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8
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Nontypeable Haemophilus influenzae Has Evolved Preferential Use of N-Acetylneuraminic Acid as a Host Adaptation. mBio 2019; 10:mBio.00422-19. [PMID: 31064827 PMCID: PMC6509186 DOI: 10.1128/mbio.00422-19] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Host-adapted bacterial pathogens such as NTHi cannot survive out of their host environment and have evolved host-specific mechanisms to obtain nutrients and evade the immune response. Relatively few of these host adaptations have been characterized at the molecular level. NTHi utilizes sialic acid as a nutrient and also incorporates this sugar into LOS, which is important in biofilm formation and immune evasion. In the present study, we showed that NTHi has evolved to preferentially utilize the Neu5Ac form of sialic acid. This adaptation is due to the substrate preference of the enzyme CMP-Neu5Ac synthetase, which synthesizes the activated form of Neu5Ac for macromolecule biosynthesis. This adaptation allows NTHi to evade killing by a human antibody response against the nonhuman sialic acid Neu5Gc. Nontypeable Haemophilus influenzae (NTHi) is a Gram-negative bacterial pathogen that is adapted exclusively to human hosts. NTHi utilizes sialic acid from the host as a carbon source and as a terminal sugar on the outer membrane glycolipid lipooligosaccharide (LOS). Sialic acid expressed on LOS is critical in NTHi biofilm formation and immune evasion. There are two major forms of sialic acids in most mammals, N-acetylneuraminic acid (Neu5Ac) and N-glycolylneuraminic acid (Neu5Gc), the latter of which is derived from Neu5Ac. Humans lack the enzyme to convert Neu5Ac to Neu5Gc and do not express Neu5Gc in normal tissues; instead, Neu5Gc is recognized as a foreign antigen. A recent study showed that dietary Neu5Gc can be acquired by NTHi colonizing humans and then presented on LOS, which acts as an antigen for the initial induction of anti-Neu5Gc antibodies. Here we examined Neu5Gc uptake and presentation on NTHi LOS. We show that, although Neu5Gc and Neu5Ac are utilized equally well as sole carbon sources, Neu5Gc is not incorporated efficiently into LOS. When equal amounts of Neu5Gc and Neu5Ac are provided in culture media, there is ∼4-fold more Neu5Ac incorporated into LOS, suggesting a bias in a step of the LOS biosynthetic pathway. CMP-Neu5Ac synthetase (SiaB) was shown to have ∼4,000-fold-higher catalytic efficiency for Neu5Ac than for Neu5Gc. These data suggest that NTHi has adapted preferential utilization of Neu5Ac, thus avoiding presentation of the nonhuman Neu5Gc in the bacterial cell surface. The selective pressure for this adaptation may represent the human antibody response to the Neu5Gc xenoantigen.
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9
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Cheng L, Li F, Li S, Lin C, Fu Q, Yin H, Tian F, Qu G, Wu J, Shen Z. A novel nicotinamide adenine dinucleotide control strategy for increasing the cell density of Haemophilus parasuis. Biotechnol Prog 2019; 35:e2794. [PMID: 30816004 DOI: 10.1002/btpr.2794] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2018] [Revised: 02/22/2019] [Accepted: 02/24/2019] [Indexed: 11/12/2022]
Abstract
Haemophilus parasuis is the causative agent of Glässer's disease and is a major source of economic losses in the swine industry each year. To enhance the production of an inactivated vaccine against H. parasuis, the availability of nicotinamide adenine dinucleotide (NAD) must be carefully controlled to ensure a sufficiently high cell density of H. parasuis. In the present study, the real-time viable cell density of H. parasuis was calculated based on the capacitance of the culture. By assessing the relationship between capacitance and viable cell density/NAD concentration, the NAD supply rate could be adjusted in real time to maintain the NAD concentration at a set value based on the linear relationship between capacitance and NAD consumption. The linear relationship between cell density and addition of NAD indicated that 7.138 × 109 NAD molecules were required to satisfy per cell growth. Five types of NAD supply strategy were used to maintain different NAD concentration for H. parasuis cultivation, and the results revealed that the highest viable cell density (8.57, OD600 ) and cell count (1.57 × 1010 CFU/mL) were obtained with strategy III (NAD concentration maintained at 30 mg/L), which were 1.46- and 1.45- times more, respectively, than cultures with using NAD supply strategy I (NAD concentration maintained at 10 mg/L). An extremely high cell density of H. parasuis was achieved using this NAD supply strategy, and the results demonstrated a convenient and reliable method for determining the real-time viable cell density relative to NAD concentration. Moreover, this method provides a theoretical foundation and an efficient approach for high cell density cultivation of other auxotroph bacteria.
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Affiliation(s)
- Likun Cheng
- Post-doctoral Scientific Research Workstation, Shandong Binzhou Animal Science and Veterinary Medicine Academy, Binzhou, China.,Key Laboratory of Binzhou High Cell Density Fermentation, Shandong Lvdu Bio-science and Technology Co. Ltd., Binzhou, China
| | - Feng Li
- Post-doctoral Scientific Research Workstation, Shandong Binzhou Animal Science and Veterinary Medicine Academy, Binzhou, China.,Key Laboratory of Binzhou High Cell Density Fermentation, Shandong Lvdu Bio-science and Technology Co. Ltd., Binzhou, China
| | - Shuguang Li
- Post-doctoral Scientific Research Workstation, Shandong Binzhou Animal Science and Veterinary Medicine Academy, Binzhou, China.,Key Laboratory of Binzhou High Cell Density Fermentation, Shandong Lvdu Bio-science and Technology Co. Ltd., Binzhou, China
| | - Chuwen Lin
- Post-doctoral Scientific Research Workstation, Shandong Binzhou Animal Science and Veterinary Medicine Academy, Binzhou, China
| | - Qiang Fu
- Post-doctoral Scientific Research Workstation, Shandong Binzhou Animal Science and Veterinary Medicine Academy, Binzhou, China
| | - Huanhuan Yin
- Post-doctoral Scientific Research Workstation, Shandong Binzhou Animal Science and Veterinary Medicine Academy, Binzhou, China
| | - Fengrong Tian
- Post-doctoral Scientific Research Workstation, Shandong Binzhou Animal Science and Veterinary Medicine Academy, Binzhou, China
| | - Guanggang Qu
- Post-doctoral Scientific Research Workstation, Shandong Binzhou Animal Science and Veterinary Medicine Academy, Binzhou, China
| | - Jiaqiang Wu
- Institution of Poultry, Shandong Academy of Agricultural Science, Jinan, China
| | - Zhiqiang Shen
- Post-doctoral Scientific Research Workstation, Shandong Binzhou Animal Science and Veterinary Medicine Academy, Binzhou, China
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10
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Cintra FDO, Takagi M. SELECTION OF A MATHEMATICAL MODEL FOR THE KINETICS OF Haemophilus influenzae TYPE B USING AKAIKE’S INFORMATION CRITERION. BRAZILIAN JOURNAL OF CHEMICAL ENGINEERING 2018. [DOI: 10.1590/0104-6632.20180354s20170085] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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11
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Liu Y, Clement J, Grant R, Sachdev P, Braidy N. Quantitation of NAD+: Why do we need to measure it? Biochim Biophys Acta Gen Subj 2018; 1862:2527-2532. [PMID: 30048742 DOI: 10.1016/j.bbagen.2018.07.023] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2018] [Revised: 07/19/2018] [Accepted: 07/20/2018] [Indexed: 11/17/2022]
Abstract
BACKGROUND Nicotinamide adenine dinucleotide (NAD+) is an essential pyridine nucleotide that is currently investigated as an important target to extend lifespan and health span. Age-related NAD+ depletion due to the accumulation of oxidative stress is associated with reduced energy production, impaired DNA repair and genomic instability. SCOPE OF REVIEW NAD+ levels can be elevated therapeutically using NAD+ precursors or through lifestyle modifications including exercise and caloric restriction. However, high amounts of NAD+ may be detrimental in cancer progression and may have deleterious immunogenic roles. MAJOR CONCLUSIONS Standardized quantitation of NAD+ and related metabolites may therefore represent an important component of NAD+ therapy. GENERAL SIGNIFICANCE Quantitation of NAD+ may serve dual roles not only as an ageing biomarker, but also as a diagnostic tool for the prevention of malignant disorders.
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Affiliation(s)
- Yue Liu
- Centre for Healthy Brain Ageing, School of Psychiatry, University of New South Wales, Sydney, Australia
| | | | - Ross Grant
- Australasian Research Institute, Sydney Adventist Hospital, Sydney, Australia; School of Medical Sciences, University of New South Wales, Sydney, Australia
| | - Perminder Sachdev
- Centre for Healthy Brain Ageing, School of Psychiatry, University of New South Wales, Sydney, Australia; Neuropsychiatric Institute, Euroa Centre, Prince of Wales Hospital, Sydney, Australia
| | - Nady Braidy
- Centre for Healthy Brain Ageing, School of Psychiatry, University of New South Wales, Sydney, Australia.
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12
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Spaans SK, Weusthuis RA, van der Oost J, Kengen SWM. NADPH-generating systems in bacteria and archaea. Front Microbiol 2015; 6:742. [PMID: 26284036 PMCID: PMC4518329 DOI: 10.3389/fmicb.2015.00742] [Citation(s) in RCA: 197] [Impact Index Per Article: 21.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2015] [Accepted: 07/06/2015] [Indexed: 12/22/2022] Open
Abstract
Reduced nicotinamide adenine dinucleotide phosphate (NADPH) is an essential electron donor in all organisms. It provides the reducing power that drives numerous anabolic reactions, including those responsible for the biosynthesis of all major cell components and many products in biotechnology. The efficient synthesis of many of these products, however, is limited by the rate of NADPH regeneration. Hence, a thorough understanding of the reactions involved in the generation of NADPH is required to increase its turnover through rational strain improvement. Traditionally, the main engineering targets for increasing NADPH availability have included the dehydrogenase reactions of the oxidative pentose phosphate pathway and the isocitrate dehydrogenase step of the tricarboxylic acid (TCA) cycle. However, the importance of alternative NADPH-generating reactions has recently become evident. In the current review, the major canonical and non-canonical reactions involved in the production and regeneration of NADPH in prokaryotes are described, and their key enzymes are discussed. In addition, an overview of how different enzymes have been applied to increase NADPH availability and thereby enhance productivity is provided.
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Affiliation(s)
| | - Ruud A. Weusthuis
- Bioprocess Engineering, Wageningen UniversityWageningen, Netherlands
| | - John van der Oost
- Laboratory of Microbiology, Wageningen UniversityWageningen, Netherlands
| | - Servé W. M. Kengen
- Laboratory of Microbiology, Wageningen UniversityWageningen, Netherlands
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13
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Su YC, Mukherjee O, Singh B, Hallgren O, Westergren-Thorsson G, Hood D, Riesbeck K. Haemophilus influenzae P4 Interacts With Extracellular Matrix Proteins Promoting Adhesion and Serum Resistance. J Infect Dis 2015; 213:314-23. [PMID: 26153407 DOI: 10.1093/infdis/jiv374] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2015] [Accepted: 06/26/2015] [Indexed: 02/07/2023] Open
Abstract
Interaction with the extracellular matrix (ECM) is one of the successful colonization strategies employed by nontypeable Haemophilus influenzae (NTHi). Here we identified Haemophilus lipoprotein e (P4) as a receptor for ECM proteins. Purified recombinant P4 displayed a high binding affinity for laminin (Kd = 9.26 nM) and fibronectin (Kd = 10.19 nM), but slightly less to vitronectin (Kd = 16.51 nM). A P4-deficient NTHi mutant showed a significantly decreased binding to these ECM components. Vitronectin acquisition conferred serum resistance to both P4-expressing NTHi and Escherichia coli transformants. P4-mediated bacterial adherence to pharynx, type II alveolar, and bronchial epithelial cells was mainly attributed to fibronectin. Importantly, a significantly reduced bacterial infection was observed in the middle ear of the Junbo mouse model when NTHi was devoid of P4. In conclusion, our data provide new insight into the role of P4 as an important factor for Haemophilus colonization and subsequent respiratory tract infection.
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Affiliation(s)
- Yu-Ching Su
- Clinical Microbiology, Department of Translational Medicine, Lund University, Malmö
| | - Oindrilla Mukherjee
- Clinical Microbiology, Department of Translational Medicine, Lund University, Malmö
| | - Birendra Singh
- Clinical Microbiology, Department of Translational Medicine, Lund University, Malmö
| | - Oskar Hallgren
- Department for Experimental Medical Sciences Department of Respiratory Medicine and Allergology, Lund University, Sweden
| | | | - Derek Hood
- Mammalian Genetics Unit, MRC Harwell, Harwell Science & Innovation Campus, Oxfordshire, United Kingdom
| | - Kristian Riesbeck
- Clinical Microbiology, Department of Translational Medicine, Lund University, Malmö
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Zaheer R, Klima CL, McAllister TA. Expeditious screening of candidate proteins for microbial vaccines. J Microbiol Methods 2015; 116:53-9. [PMID: 26149626 DOI: 10.1016/j.mimet.2015.06.018] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2015] [Revised: 06/26/2015] [Accepted: 06/27/2015] [Indexed: 11/18/2022]
Abstract
Advancements in high-throughput "omics" technologies have revolutionized the way vaccine candidates are identified. Now every surface expressed protein that an organism produces can be identified in silico and possibly made available for the rapid development of recombinant/subunit vaccines. However, evaluating the antigenicity of a large number of candidate proteins is an immense challenge, typically requiring cloning of several hundred candidates followed by immunogenicity screening. Here we report the development of a rapid, high-throughput method for screening candidate proteins for vaccines. This method involves utilizing a coupled, cell-free transcription-translation system to screen tagged proteins that are captured at the C-termini using appropriate ligand coated wells in 96 well ELISA plates. The template DNA for the cell-free expression is generated by two sequential PCRs and includes gene coding sequences, promoter, terminator, other necessary cis-acting elements and appropriate tag sequences. The process generates expressible candidate proteins containing two different peptide tags at the N- and the C-termini of the protein molecules. Proteins are screened in parallel for their quantity and immunoreactivity with N-terminal tag antibodies and antisera raised against the pathogen of interest, respectively. Normalization against the total detectable bound protein in the control wells allows for the identification of highly immunoreactive candidates. For this study we selected 30 representatives of >300 potential candidate proteins from Mannheimia haemolytica, a bacterial agent of pneumonia in feedlot cattle for expression with N-terminal Strep-II and C-terminal His(x6)-tag and evaluated their relative immunoreactivities using Strep-tactin-HRP and rabbit antisera generated against M. haemolytica. Using this system we were able to swiftly and quantitatively analyze and rank the suitability of proteins to identify potentially viable vaccine candidates, with the majority of the high ranking candidates being associated with virulence and pathogenicity. The system is adaptable to any bacterial target and presents an alternative to conventional laborious cloning, expression and screening procedures.
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Affiliation(s)
- Rahat Zaheer
- Lethbridge Research Centre, Agriculture and Agri-Food Canada, Lethbridge, AB T1J 4B1 Canada
| | - Cassidy L Klima
- Lethbridge Research Centre, Agriculture and Agri-Food Canada, Lethbridge, AB T1J 4B1 Canada
| | - Tim A McAllister
- Lethbridge Research Centre, Agriculture and Agri-Food Canada, Lethbridge, AB T1J 4B1 Canada.
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15
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Post DMB, Held JM, Ketterer MR, Phillips NJ, Sahu A, Apicella MA, Gibson BW. Comparative analyses of proteins from Haemophilus influenzae biofilm and planktonic populations using metabolic labeling and mass spectrometry. BMC Microbiol 2014; 14:329. [PMID: 25551439 PMCID: PMC4302520 DOI: 10.1186/s12866-014-0329-9] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2014] [Accepted: 12/16/2014] [Indexed: 11/25/2022] Open
Abstract
Background Non-typeable H. influenzae (NTHi) is a nasopharyngeal commensal that can become an opportunistic pathogen causing infections such as otitis media, pneumonia, and bronchitis. NTHi is known to form biofilms. Resistance of bacterial biofilms to clearance by host defense mechanisms and antibiotic treatments is well-established. In the current study, we used stable isotope labeling by amino acids in cell culture (SILAC) to compare the proteomic profiles of NTHi biofilm and planktonic organisms. Duplicate continuous-flow growth chambers containing defined media with either “light” (L) isoleucine or “heavy” (H) 13C6-labeled isoleucine were used to grow planktonic (L) and biofilm (H) samples, respectively. Bacteria were removed from the chambers, mixed based on weight, and protein extracts were generated. Liquid chromatography-mass spectrometry (LC-MS) was performed on the tryptic peptides and 814 unique proteins were identified with 99% confidence. Results Comparisons of the NTHi biofilm to planktonic samples demonstrated that 127 proteins showed differential expression with p-values ≤0.05. Pathway analysis demonstrated that proteins involved in energy metabolism, protein synthesis, and purine, pyrimidine, nucleoside, and nucleotide processes showed a general trend of downregulation in the biofilm compared to planktonic organisms. Conversely, proteins involved in transcription, DNA metabolism, and fatty acid and phospholipid metabolism showed a general trend of upregulation under biofilm conditions. Selected reaction monitoring (SRM)-MS was used to validate a subset of these proteins; among these were aerobic respiration control protein ArcA, NAD nucleotidase and heme-binding protein A. Conclusions The present proteomic study indicates that the NTHi biofilm exists in a semi-dormant state with decreased energy metabolism and protein synthesis yet is still capable of managing oxidative stress and in acquiring necessary cofactors important for biofilm survival. Electronic supplementary material The online version of this article (doi:10.1186/s12866-014-0329-9) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Deborah M B Post
- The Buck Institute for Research on Aging, Novato, CA, 94945, USA.
| | - Jason M Held
- Washington University School of Medicine, St. Louis, MO, 63110, USA.
| | | | - Nancy J Phillips
- The University of California San Francisco, San Francisco, CA, 94143, USA.
| | - Alexandria Sahu
- The Buck Institute for Research on Aging, Novato, CA, 94945, USA.
| | | | - Bradford W Gibson
- The Buck Institute for Research on Aging, Novato, CA, 94945, USA. .,The University of California San Francisco, San Francisco, CA, 94143, USA.
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16
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Roier S, Blume T, Klug L, Wagner GE, Elhenawy W, Zangger K, Prassl R, Reidl J, Daum G, Feldman MF, Schild S. A basis for vaccine development: Comparative characterization of Haemophilus influenzae outer membrane vesicles. Int J Med Microbiol 2014; 305:298-309. [PMID: 25592265 DOI: 10.1016/j.ijmm.2014.12.005] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2014] [Revised: 12/09/2014] [Accepted: 12/14/2014] [Indexed: 11/29/2022] Open
Abstract
Outer membrane vesicles (OMVs) are spherical and bilayered particles that are naturally released from the outer membrane (OM) of Gram-negative bacteria. They have been proposed to possess several biological roles in pathogenesis and interbacterial interactions. Additionally, OMVs have been suggested as potential vaccine candidates against infections caused by pathogenic bacteria like Haemophilus influenzae, a human pathogen of the respiratory tract. Unfortunately, there is still a lack of fundamental knowledge regarding OMV biogenesis, protein sorting into OMVs, OMV size and quantity, as well as OMV composition in H. influenzae. Thus, this study comprehensively characterized and compared OMVs and OMs derived from heterologous encapsulated as well as nonencapsulated H. influenzae strains. Semiquantitative immunoblot analysis revealed that certain OM proteins are enriched or excluded in OMVs suggesting the presence of regulated protein sorting mechanisms into OMVs as well as interconnected OMV biogenesis mechanisms in H. influenzae. Nanoparticle tracking analysis, transmission electron microscopy, as well as protein and lipooligosaccharide quantifications demonstrated that heterologous H. influenzae strains differ in their OMV size and quantity. Lipidomic analyses identified palmitic acid as the most abundant fatty acid, while phosphatidylethanolamine was found to be the most dominant phospholipid present in OMVs and the OM of all strains tested. Proteomic analysis confirmed that H. influenzae OMVs contain vaccine candidate proteins as well as important virulence factors. These findings contribute to the understanding of OMV biogenesis as well as biological roles of OMVs and, in addition, may be important for the future development of OMV based vaccines against H. influenzae infections.
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Affiliation(s)
- Sandro Roier
- Institute of Molecular Biosciences, University of Graz, NAWI Graz, BioTechMed-Graz, Humboldtstraße 50, A-8010 Graz, Austria
| | - Thomas Blume
- Institute of Molecular Biosciences, University of Graz, NAWI Graz, BioTechMed-Graz, Humboldtstraße 50, A-8010 Graz, Austria
| | - Lisa Klug
- Institute of Biochemistry, Graz University of Technology, NAWI Graz, BioTechMed-Graz, Petersgasse 12/2, A-8010 Graz, Austria
| | - Gabriel E Wagner
- Institute of Chemistry/Organic and Bioorganic Chemistry, University of Graz, NAWI Graz, BioTechMed-Graz, Heinrichstraße 28, A-8010 Graz, Austria
| | - Wael Elhenawy
- Alberta Glycomics Centre, Department of Biological Sciences, University of Alberta, CW405 Biological Sciences Building, Edmonton, AB, Canada T6G 2E9
| | - Klaus Zangger
- Institute of Chemistry/Organic and Bioorganic Chemistry, University of Graz, NAWI Graz, BioTechMed-Graz, Heinrichstraße 28, A-8010 Graz, Austria
| | - Ruth Prassl
- Institute of Biophysics, Medical University of Graz, BioTechMed-Graz, Harrachgasse 21, A-8010 Graz, Austria
| | - Joachim Reidl
- Institute of Molecular Biosciences, University of Graz, NAWI Graz, BioTechMed-Graz, Humboldtstraße 50, A-8010 Graz, Austria
| | - Günther Daum
- Institute of Biochemistry, Graz University of Technology, NAWI Graz, BioTechMed-Graz, Petersgasse 12/2, A-8010 Graz, Austria
| | - Mario F Feldman
- Alberta Glycomics Centre, Department of Biological Sciences, University of Alberta, CW405 Biological Sciences Building, Edmonton, AB, Canada T6G 2E9
| | - Stefan Schild
- Institute of Molecular Biosciences, University of Graz, NAWI Graz, BioTechMed-Graz, Humboldtstraße 50, A-8010 Graz, Austria.
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17
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Janowicz DM, Zwickl BW, Fortney KR, Katz BP, Bauer ME. Outer membrane protein P4 is not required for virulence in the human challenge model of Haemophilus ducreyi infection. BMC Microbiol 2014; 14:166. [PMID: 24961160 PMCID: PMC4081464 DOI: 10.1186/1471-2180-14-166] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2014] [Accepted: 06/04/2014] [Indexed: 01/14/2023] Open
Abstract
Background Bacterial lipoproteins often play important roles in pathogenesis and can stimulate protective immune responses. Such lipoproteins are viable vaccine candidates. Haemophilus ducreyi, which causes the sexually transmitted disease chancroid, expresses a number of lipoproteins during human infection. One such lipoprotein, OmpP4, is homologous to the outer membrane lipoprotein e (P4) of H. influenzae. In H. influenzae, e (P4) stimulates production of bactericidal and protective antibodies and contributes to pathogenesis by facilitating acquisition of the essential nutrients heme and nicotinamide adenine dinucleotide (NAD). Here, we tested the hypothesis that, like its homolog, H. ducreyi OmpP4 contributes to virulence and stimulates production of bactericidal antibodies. Results We determined that OmpP4 is broadly conserved among clinical isolates of H. ducreyi. We next constructed and characterized an isogenic ompP4 mutant, designated 35000HPompP4, in H. ducreyi strain 35000HP. To test whether OmpP4 was necessary for virulence in humans, eight healthy adults were experimentally infected. Each subject was inoculated with a fixed dose of 35000HP on one arm and three doses of 35000HPompP4 on the other arm. The overall parent and mutant pustule formation rates were 52.4% and 47.6%, respectively (P = 0.74). These results indicate that expression of OmpP4 in not necessary for H. ducreyi to initiate disease or progress to pustule formation in humans. Hyperimmune mouse serum raised against purified, recombinant OmpP4 did not promote bactericidal killing of 35000HP or phagocytosis by J774A.1 mouse macrophages in serum bactericidal and phagocytosis assays, respectively. Conclusions Our data suggest that, unlike e (P4), H. ducreyi OmpP4 is not a suitable vaccine candidate. OmpP4 may be dispensable for virulence because of redundant mechanisms in H. ducreyi for heme acquisition and NAD utilization.
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Affiliation(s)
- Diane M Janowicz
- Department of Medicine, Indiana University School of Medicine, 545 Barnhill Drive Room EH-435, Indianapolis, IN 46202, USA.
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18
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Genome-wide fitness profiling reveals adaptations required by Haemophilus in coinfection with influenza A virus in the murine lung. Proc Natl Acad Sci U S A 2013; 110:15413-8. [PMID: 24003154 DOI: 10.1073/pnas.1311217110] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Bacterial coinfection represents a major cause of morbidity and mortality in epidemics of influenza A virus (IAV). The bacterium Haemophilus influenzae typically colonizes the human upper respiratory tract without causing disease, and yet in individuals infected with IAV, it can cause debilitating or lethal secondary pneumonia. Studies in murine models have detected immune components involved in susceptibility and pathology, and yet few studies have examined bacterial factors contributing to coinfection. We conducted genome-wide profiling of the H. influenzae genes that promote its fitness in a murine model of coinfection with IAV. Application of direct, high-throughput sequencing of transposon insertion sites revealed fitness phenotypes of a bank of H. influenzae mutants in viral coinfection in comparison with bacterial infection alone. One set of virulence genes was required in nonvirally infected mice but not in coinfection, consistent with a defect in anti-bacterial defenses during coinfection. Nevertheless, a core set of genes required in both in vivo conditions indicated that many bacterial countermeasures against host defenses remain critical for coinfection. The results also revealed a subset of genes required in coinfection but not in bacterial infection alone, including the iron-sulfur cluster regulator gene, iscR, which was required for oxidative stress resistance. Overexpression of the antioxidant protein Dps in the iscR mutant restored oxidative stress resistance and ability to colonize in coinfection. The results identify bacterial stress and metabolic adaptations required in an IAV coinfection model, revealing potential targets for treatment or prevention of secondary bacterial pneumonia after viral infection.
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19
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Deka RK, Brautigam CA, Liu WZ, Tomchick DR, Norgard MV. The TP0796 lipoprotein of Treponema pallidum is a bimetal-dependent FAD pyrophosphatase with a potential role in flavin homeostasis. J Biol Chem 2013; 288:11106-21. [PMID: 23447540 DOI: 10.1074/jbc.m113.449975] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Treponema pallidum, an obligate parasite of humans and the causative agent of syphilis, has evolved the capacity to exploit host-derived metabolites for its survival. Flavin-containing compounds are essential cofactors that are required for metabolic processes in all living organisms, and riboflavin is a direct precursor of the cofactors FMN and FAD. Unlike many pathogenic bacteria, Treponema pallidum cannot synthesize riboflavin; we recently described a flavin-uptake mechanism composed of an ABC-type transporter. However, there is a paucity of information about flavin utilization in bacterial periplasms. Using a discovery-driven approach, we have identified the TP0796 lipoprotein as a previously uncharacterized Mg(2+)-dependent FAD pyrophosphatase within the ApbE superfamily. TP0796 probably plays a central role in flavin turnover by hydrolyzing exogenously acquired FAD, yielding AMP and FMN. Biochemical and structural investigations revealed that the enzyme has a unique bimetal Mg(2+) catalytic center. Furthermore, the pyrophosphatase activity is product-inhibited by AMP, indicating a possible role for this molecule in modulating FMN and FAD levels in the treponemal periplasm. The ApbE superfamily was previously thought to be involved in thiamine biosynthesis, but our characterization of TP0796 prompts a renaming of this superfamily as a periplasmic flavin-trafficking protein (Ftp). TP0796 is the first structurally and biochemically characterized FAD pyrophosphate enzyme in bacteria. This new paradigm for a bacterial flavin utilization pathway may prove to be useful for future inhibitor design.
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Affiliation(s)
- Ranjit K Deka
- Department of Microbiology, University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA
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20
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The high-resolution crystal structure of periplasmic Haemophilus influenzae NAD nucleotidase reveals a novel enzymatic function of human CD73 related to NAD metabolism. Biochem J 2012; 441:131-41. [PMID: 21933152 DOI: 10.1042/bj20111263] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Haemophilus influenzae is a major pathogen of the respiratory tract in humans that has developed the capability to exploit host NAD(P) for its nicotinamide dinucleotide requirement. This strategy is organized around a periplasmic enzyme termed NadN (NAD nucleotidase), which plays a central role by degrading NAD into adenosine and NR (nicotinamide riboside), the latter being subsequently internalized by a specific permease. We performed a biochemical and structural investigation on H. influenzae NadN which determined that the enzyme is a Zn2+-dependent 5'-nucleotidase also endowed with NAD(P) pyrophosphatase activity. A 1.3 Å resolution structural analysis revealed a remarkable conformational change that occurs during catalysis between the open and closed forms of the enzyme. NadN showed a broad substrate specificity, recognizing either mono- or di-nucleotide nicotinamides and different adenosine phosphates with a maximal activity on 5'-adenosine monophosphate. Sequence and structural analysis of H. influenzae NadN led us to discover that human CD73 is capable of processing both NAD and NMN, therefore disclosing a possible novel function of human CD73 in systemic NAD metabolism. Our data may prove to be useful for inhibitor design and disclosed unanticipated fascinating evolutionary relationships.
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21
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Hartog AF, van Herk T, Wever R. Efficient Regeneration of NADPH in a 3-Enzyme Cascade Reaction by in situ Generation of Glucose 6-Phosphate from Glucose and Pyrophosphate. Adv Synth Catal 2011. [DOI: 10.1002/adsc.201100198] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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22
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Determining the extremes of the cellular NAD(H) level by using an Escherichia coli NAD(+)-auxotrophic mutant. Appl Environ Microbiol 2011; 77:6133-40. [PMID: 21742902 DOI: 10.1128/aem.00630-11] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
NAD (NAD(+)) and its reduced form (NADH) are omnipresent cofactors in biological systems. However, it is difficult to determine the extremes of the cellular NAD(H) level in live cells because the NAD(+) level is tightly controlled by a biosynthesis regulation mechanism. Here, we developed a strategy to determine the extreme NAD(H) levels in Escherichia coli cells that were genetically engineered to be NAD(+) auxotrophic. First, we expressed the ntt4 gene encoding the NAD(H) transporter in the E. coli mutant YJE001, which had a deletion of the nadC gene responsible for NAD(+) de novo biosynthesis, and we showed NTT4 conferred on the mutant strain better growth in the presence of exogenous NAD(+). We then constructed the NAD(+)-auxotrophic mutant YJE003 by disrupting the essential gene nadE, which is responsible for the last step of NAD(+) biosynthesis in cells harboring the ntt4 gene. The minimal NAD(+) level was determined in M9 medium in proliferating YJE003 cells that were preloaded with NAD(+), while the maximal NAD(H) level was determined by exposing the cells to high concentrations of exogenous NAD(H). Compared with supplementation of NADH, cells grew faster and had a higher intracellular NAD(H) level when NAD(+) was fed. The intracellular NAD(H) level increased with the increase of exogenous NAD(+) concentration, until it reached a plateau. Thus, a minimal NAD(H) level of 0.039 mM and a maximum of 8.49 mM were determined, which were 0.044× and 9.6× those of wild-type cells, respectively. Finally, the potential application of this strategy in biotechnology is briefly discussed.
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23
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Zhai RG, Rizzi M, Garavaglia S. Nicotinamide/nicotinic acid mononucleotide adenylyltransferase, new insights into an ancient enzyme. Cell Mol Life Sci 2009; 66:2805-18. [PMID: 19448972 PMCID: PMC11115848 DOI: 10.1007/s00018-009-0047-x] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2009] [Revised: 04/16/2009] [Accepted: 04/28/2009] [Indexed: 12/14/2022]
Abstract
Nicotinamide/nicotinic acid mononucleotide adenylyltransferase (NMNAT) has long been known as the master enzyme in NAD biosynthesis in living organisms. A burst of investigations on NMNAT, going beyond enzymology, have paralleled increasing discoveries of key roles played by NAD homeostasis in a number or patho-physiological conditions. The availability of in-depth kinetics and structural enzymology analyses carried out on NMNATs from different organisms offer a powerful tool for uncovering fascinating evolutionary relationships. On the other hand, additional functions featuring NMNAT have emerged from investigations aimed at unraveling the molecular mechanisms responsible for complex biological phenomena such as neurodegeneration. NMNAT appears to be a multifunctional protein that sits both at the core of central metabolism and at a crossroads of multiple cellular processes. The resultant wealth of biochemical data has built a robust framework upon which design of NMNAT activators, inhibitors or enzyme variants of potential medical interest can be based.
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Affiliation(s)
- Rong Grace Zhai
- Department of Molecular and Cellular Pharmacology, Neuroscience Center, Miller School of Medicine, University of Miami, Miami, FL 33136 USA
| | - Menico Rizzi
- DiSCAFF, University of Piemonte Orientale “A. Avogadro”, Via Bovio, 6, 28100 Novara, Italy
| | - Silvia Garavaglia
- DiSCAFF, University of Piemonte Orientale “A. Avogadro”, Via Bovio, 6, 28100 Novara, Italy
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24
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Structure and function of NAD kinase and NADP phosphatase: key enzymes that regulate the intracellular balance of NAD(H) and NADP(H). Biosci Biotechnol Biochem 2008; 72:919-30. [PMID: 18391451 DOI: 10.1271/bbb.70738] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The functions of NAD(H) (NAD(+) and NADH) and NADP(H) (NADP(+) and NADPH) are undoubtedly significant and distinct. Hence, regulation of the intracellular balance of NAD(H) and NADP(H) is important. The key enzymes involved in the regulation are NAD kinase and NADP phosphatase. In 2000, we first succeeded in identifying the gene for NAD kinase, thereby facilitating worldwide studies of this enzyme from various organisms, including eubacteria, archaea, yeast, plants, and humans. Molecular biological study has revealed the physiological function of this enzyme, that is to say, the significance of NADP(H), in some model organisms. Structural research has elucidated the tertiary structure of the enzyme, the details of substrate-binding sites, and the catalytic mechanism. Research on NAD kinase also led to the discovery of archaeal NADP phosphatase. In this review, we summarize the physiological functions, applications, and structure of NAD kinase, and the way we discovered archaeal NADP phosphatase.
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25
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Morton DJ, VanWagoner TM, Seale TW, Whitby PW, Stull TL. Catalase as a source of both X- and V-factor for Haemophilus influenzae. FEMS Microbiol Lett 2007; 279:157-61. [PMID: 18093136 DOI: 10.1111/j.1574-6968.2007.01020.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
Haemophilus influenzae requires two growth factors, designated factor X (porphyrin) and factor V (NAD). Mammalian catalases contain both bound heme and NADPH. This study shows that catalase can supply both factors X and V to H. influenzae in vitro, thus representing a potential in vivo source of these essential growth factors.
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Affiliation(s)
- Daniel J Morton
- Department of Pediatrics, University of Oklahoma Health Sciences Center, 940 NE 13th Street, Oklahoma City, OK 73104, USA
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26
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Moraxella catarrhalis synthesizes an autotransporter that is an acid phosphatase. J Bacteriol 2007; 190:1459-72. [PMID: 18065547 DOI: 10.1128/jb.01688-07] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Moraxella catarrhalis O35E was shown to synthesize a 105-kDa protein that has similarity to both acid phosphatases and autotransporters. The N-terminal portion of the M. catarrhalis acid phosphatase A (MapA) was most similar (the BLAST probability score was 10(-10)) to bacterial class A nonspecific acid phosphatases. The central region of the MapA protein had similarity to passenger domains of other autotransporter proteins, whereas the C-terminal portion of MapA resembled the translocation domain of conventional autotransporters. Cloning and expression of the M. catarrhalis mapA gene in Escherichia coli confirmed the presence of acid phosphatase activity in the MapA protein. The MapA protein was shown to be localized to the outer membrane of M. catarrhalis and was not detected either in the soluble cytoplasmic fraction from disrupted M. catarrhalis cells or in the spent culture supernatant fluid from M. catarrhalis. Use of the predicted MapA translocation domain in a fusion construct with the passenger domain from another predicted M. catarrhalis autotransporter confirmed the translocation ability of this MapA domain. Inactivation of the mapA gene in M. catarrhalis strain O35E reduced the acid phosphatase activity expressed by this organism, and this mutation could be complemented in trans with the wild-type mapA gene. Nucleotide sequence analysis of the mapA gene from six M. catarrhalis strains showed that this protein was highly conserved among strains of this pathogen. Site-directed mutagenesis of a critical histidine residue (H233A) in the predicted active site of the acid phosphatase domain in MapA eliminated acid phosphatase activity in the recombinant MapA protein. This is the first description of an autotransporter protein that expresses acid phosphatase activity.
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27
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Vogl C, Grill S, Schilling O, Stülke J, Mack M, Stolz J. Characterization of riboflavin (vitamin B2) transport proteins from Bacillus subtilis and Corynebacterium glutamicum. J Bacteriol 2007; 189:7367-75. [PMID: 17693491 PMCID: PMC2168442 DOI: 10.1128/jb.00590-07] [Citation(s) in RCA: 93] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2007] [Accepted: 08/03/2007] [Indexed: 01/12/2023] Open
Abstract
Riboflavin (vitamin B(2)) is the direct precursor of the flavin cofactors flavin mononucleotide and flavin adenine dinucleotide, essential components of cellular biochemistry. In this work we investigated the unrelated proteins YpaA from Bacillus subtilis and PnuX from Corynebacterium glutamicum for a role in riboflavin uptake. Based on the regulation of the corresponding genes by a riboswitch mechanism, both proteins have been predicted to be involved in flavin metabolism. Moreover, their primary structures suggested that these proteins integrate into the cytoplasmic membrane. We provide experimental evidence that YpaA is a plasma membrane protein with five transmembrane domains and a cytoplasmic C terminus. In B. subtilis, riboflavin uptake was increased when ypaA was overexpressed and abolished when ypaA was deleted. Riboflavin uptake activity and the abundance of the YpaA protein were also increased when riboflavin auxotrophic mutants were grown in limiting amounts of riboflavin. YpaA-mediated riboflavin uptake was sensitive to protonophors and reduced in the absence of glucose, demonstrating that the protein requires metabolic energy for substrate translocation. In addition, we demonstrate that PnuX from C. glutamicum also is a riboflavin transporter. Transport by PnuX was not energy dependent and had high apparent affinity for riboflavin (K(m) 11 microM). Roseoflavin, a toxic riboflavin analog, appears to be a substrate of PnuX and YpaA. We propose to designate the gene names ribU for ypaA and ribM for pnuX to reflect that the encoded proteins function in riboflavin uptake and that the genes have different phylogenetic origins.
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Affiliation(s)
- Christian Vogl
- Lehrstuhl für Ernährungsphysiologie, Technische Universität München, Am Forum 5, 85350, Freising-Weihenstephan, Germany
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Morton DJ, Smith A, VanWagoner TM, Seale TW, Whitby PW, Stull TL. Lipoprotein e (P4) of Haemophilus influenzae: role in heme utilization and pathogenesis. Microbes Infect 2007; 9:932-9. [PMID: 17548224 PMCID: PMC1975679 DOI: 10.1016/j.micinf.2007.03.013] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2007] [Accepted: 03/28/2007] [Indexed: 10/23/2022]
Abstract
Lipoprotein e (P4) of Haemophilus influenzae is a phosphomonoesterase, encoded by the hel gene, that has been implicated in the acquisition of heme by this fastidious organism. However, lipoprotein e (P4) is also involved in the utilization of NAD and NMN. Some reports have concluded that the reported heme-related growth defect actually reflects a growth defect for NAD. In the current study, hel insertion mutants were constructed and a role for e (P4) in heme acquisition was demonstrated independent of its role in NAD or NMN acquisition. In addition, a rat model of infection demonstrated a role for e (P4) in the pathogenesis of invasive disease.
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Affiliation(s)
- Daniel J. Morton
- Department of Pediatrics, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma 73104
| | - Ann Smith
- School of Biological Sciences, University of Missouri-Kansas City, Kansas City, Missouri 64110
| | - Timothy M. VanWagoner
- Department of Pediatrics, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma 73104
| | - Thomas W. Seale
- Department of Pediatrics, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma 73104
| | - Paul W. Whitby
- Department of Pediatrics, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma 73104
| | - Terrence L. Stull
- Department of Pediatrics, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma 73104
- Department of Microbiology/Immunology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma 73104
- * Corresponding author Mailing address: Department of Pediatrics, CHO 2308, 940 NE 13 St, Oklahoma City, OK, 73104, Phone: (405)271-4401, Fax: (405)271-8710, E-mail:
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29
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Pollak N, Dölle C, Ziegler M. The power to reduce: pyridine nucleotides--small molecules with a multitude of functions. Biochem J 2007; 402:205-18. [PMID: 17295611 PMCID: PMC1798440 DOI: 10.1042/bj20061638] [Citation(s) in RCA: 498] [Impact Index Per Article: 29.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The pyridine nucleotides NAD and NADP play vital roles in metabolic conversions as signal transducers and in cellular defence systems. Both coenzymes participate as electron carriers in energy transduction and biosynthetic processes. Their oxidized forms, NAD+ and NADP+, have been identified as important elements of regulatory pathways. In particular, NAD+ serves as a substrate for ADP-ribosylation reactions and for the Sir2 family of NAD+-dependent protein deacetylases as well as a precursor of the calcium mobilizing molecule cADPr (cyclic ADP-ribose). The conversions of NADP+ into the 2'-phosphorylated form of cADPr or to its nicotinic acid derivative, NAADP, also result in the formation of potent intracellular calcium-signalling agents. Perhaps, the most critical function of NADP is in the maintenance of a pool of reducing equivalents which is essential to counteract oxidative damage and for other detoxifying reactions. It is well known that the NADPH/NADP+ ratio is usually kept high, in favour of the reduced form. Research within the past few years has revealed important insights into how the NADPH pool is generated and maintained in different subcellular compartments. Moreover, tremendous progress in the molecular characterization of NAD kinases has established these enzymes as vital factors for cell survival. In the present review, we summarize recent advances in the understanding of the biosynthesis and signalling functions of NAD(P) and highlight the new insights into the molecular mechanisms of NADPH generation and their roles in cell physiology.
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Affiliation(s)
- Nadine Pollak
- Department of Molecular Biology, University of Bergen, Thormøhlensgate 55, N-5008 Bergen, Norway
| | - Christian Dölle
- Department of Molecular Biology, University of Bergen, Thormøhlensgate 55, N-5008 Bergen, Norway
| | - Mathias Ziegler
- Department of Molecular Biology, University of Bergen, Thormøhlensgate 55, N-5008 Bergen, Norway
- To whom correspondence should be addressed (email )
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30
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Gerlach G, Reidl J. NAD+ utilization in Pasteurellaceae: simplification of a complex pathway. J Bacteriol 2006; 188:6719-27. [PMID: 16980474 PMCID: PMC1595515 DOI: 10.1128/jb.00432-06] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Affiliation(s)
- Gabriele Gerlach
- Institut für Hygiene und Mikrobiologie, Universität Würzburg, Josef Schneider Str. 2, E1, 97080 Würzburg, Germany
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31
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Kawai S, Fukuda C, Mukai T, Murata K. MJ0917 in archaeon Methanococcus jannaschii is a novel NADP phosphatase/NAD kinase. J Biol Chem 2005; 280:39200-7. [PMID: 16192277 DOI: 10.1074/jbc.m506426200] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
NAD kinase phosphorylates NAD(+) to form NADP(+). Conversely, NADP phosphatase, which has not yet been identified, dephosphorylates NADP(+) to produce NAD(+). Among the NAD kinase homologs, the primary structure of MJ0917 of hyperthermophilic archaeal Methanococcus jannaschii is unique. MJ0917 possesses an NAD kinase homologous region in its C-terminal half and an inositol-1-phosphatase homologous region in its N-terminal half. In this study, MJ0917 was biochemically shown to possess both NAD kinase and phosphatase activities toward NADP(+), NADPH, and fructose 1,6-bisphosphate, but not toward inositol 1-phosphate. With regard to the phosphatase activity, kinetic values indicated that NADP(+) is the preferred substrate and that MJ0917 would function as a novel NADP phosphatase/NAD kinase showing conflicting dual activities, viz. synthesis and degradation of an essential NADP(+). Furthermore, in vitro analysis of MJ0917 showed that, although MJ0917 could supply NADP(+), it prevented excess accumulation of NADP(+); thus, it has the ability to maintain a high NAD(+)/NADP(+) ratio, whereas 5'-AMP would decrease this ratio. The evolutionary process during which MJ0917 arose is also discussed.
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Affiliation(s)
- Shigeyuki Kawai
- Department of Basic and Applied Molecular Biotechnology, Graduate School of Agriculture, Kyoto University, Uji, Kyoto 611-0011, Japan
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32
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Merdanovic M, Sauer E, Reidl J. Coupling of NAD+ biosynthesis and nicotinamide ribosyl transport: characterization of NadR ribonucleotide kinase mutants of Haemophilus influenzae. J Bacteriol 2005; 187:4410-20. [PMID: 15968050 PMCID: PMC1151767 DOI: 10.1128/jb.187.13.4410-4420.2005] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Previously, we characterized a pathway necessary for the processing of NAD+ and for uptake of nicotinamide riboside (NR) in Haemophilus influenzae. Here we report on the role of NadR, which is essential for NAD+ utilization in this organism. Different NadR variants with a deleted ribonucleotide kinase domain or with a single amino acid change were characterized in vitro and in vivo with respect to cell viability, ribonucleotide kinase activity, and NR transport. The ribonucleotide kinase mutants were viable only in a nadV+ (nicotinamide phosphoribosyltransferase) background, indicating that the ribonucleotide kinase domain is essential for cell viability in H. influenzae. Mutations located in the Walker A and B motifs and the LID region resulted in deficiencies in both NR phosphorylation and NR uptake. The ribonucleotide kinase function of NadR was found to be feedback controlled by NAD+ under in vitro conditions and by NAD+ utilization in vivo. Taken together, our data demonstrate that the NR phosphorylation step is essential for both NR uptake across the inner membrane and NAD+ synthesis and is also involved in controlling the NAD+ biosynthesis rate.
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Affiliation(s)
- Melisa Merdanovic
- Institut für Hygiene und Mikrobiologie, Universität Würzburg, Josef Schneider Str. 2, E1, 97080 Würzburg, Germany
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33
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Grose JH, Bergthorsson U, Xu Y, Sterneckert J, Khodaverdian B, Roth JR. Assimilation of nicotinamide mononucleotide requires periplasmic AphA phosphatase in Salmonella enterica. J Bacteriol 2005; 187:4521-30. [PMID: 15968063 PMCID: PMC1151756 DOI: 10.1128/jb.187.13.4521-4530.2005] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Salmonella enterica can obtain pyridine from exogenous nicotinamide mononucleotide (NMN) by three routes. In route 1, nicotinamide is removed from NMN in the periplasm and enters the cell as the free base. In route 2, described here, phosphate is removed from NMN in the periplasm by acid phosphatase (AphA), and the produced nicotinamide ribonucleoside (NmR) enters the cell via the PnuC transporter. Internal NmR is then converted back to NMN by the NmR kinase activity of NadR. Route 3 is seen only in pnuC* transporter mutants, which import NMN intact and can therefore grow on lower levels of NMN. Internal NMN produced by either route 2 or route 3 is deamidated to nicotinic acid mononucleotide and converted to NAD by the biosynthetic enzymes NadD and NadE.
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Affiliation(s)
- Julianne H Grose
- Department of Biology, University of Utah, Salt Lake City, Utah 84112, USA
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34
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Krebs C, Adriouch S, Braasch F, Koestner W, Leiter EH, Seman M, Lund FE, Oppenheimer N, Haag F, Koch-Nolte F. CD38 controls ADP-ribosyltransferase-2-catalyzed ADP-ribosylation of T cell surface proteins. THE JOURNAL OF IMMUNOLOGY 2005; 174:3298-305. [PMID: 15749861 DOI: 10.4049/jimmunol.174.6.3298] [Citation(s) in RCA: 75] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
ADP-ribosyltransferase-2 (ART2), a GPI-anchored, toxin-related ADP-ribosylating ectoenzyme, is prominently expressed by murine T cells but not by B cells. Upon exposure of T cells to NAD, the substrate for ADP-ribosylation, ART2 catalyzes ADP-ribosylation of the P2X7 purinoceptor and other functionally important cell surface proteins. This in turn activates P2X7 and induces exposure of phosphatidylserine and shedding of CD62L. CD38, a potent ecto-NAD-glycohydrolase, is strongly expressed by most B cells but only weakly by T cells. Following incubation with NAD, CD38-deficient splenocytes exhibited lower NAD-glycohydrolase activity and stronger ADP-ribosylation of cell surface proteins than their wild-type counterparts. Depletion of CD38(high) cells from wild-type splenocytes resulted in stronger ADP-ribosylation on the remaining cells. Similarly, treatment of total splenocytes with the CD38 inhibitor nicotinamide 2'-deoxy-2'-fluoroarabinoside adenine dinucleotide increased the level of cell surface ADP-ribosylation. Furthermore, the majority of T cells isolated from CD38-deficient mice "spontaneously" exposed phosphatidylserine and lacked CD62L, most likely reflecting previous encounter with ecto-NAD. Our findings support the notion that ecto-NAD functions as a signaling molecule following its release from cells by lytic or nonlytic mechanisms. ART2 can sense and translate the local concentration of ecto-NAD into corresponding levels of ADP-ribosylated cell surface proteins, whereas CD38 controls the level of cell surface protein ADP-ribosylation by limiting the substrate availability for ART2.
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Affiliation(s)
- Christian Krebs
- Institute of Immunology, University Hospital, Hamburg, Germany
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35
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Sauer E, Merdanovic M, Mortimer AP, Bringmann G, Reidl J. PnuC and the utilization of the nicotinamide riboside analog 3-aminopyridine in Haemophilus influenzae. Antimicrob Agents Chemother 2005; 48:4532-41. [PMID: 15561822 PMCID: PMC529221 DOI: 10.1128/aac.48.12.4532-4541.2004] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The utilization pathway for the uptake of NAD and nicotinamide riboside was previously characterized for Haemophilus influenzae. We now report on the cellular location, topology, and substrate specificity of PnuC. pnuC of H. influenzae is only distantly related to pnuC of Escherichia coli and Salmonella enterica serovar Typhimurium. When E. coli PnuC was expressed in an H. influenzae pnuC mutant, it was able to take up only nicotinamide riboside and not nicotinamide mononucleotide. Therefore, we postulated that PnuC transporters in general possess specificity for nicotinamide riboside. Earlier studies showed that 3-aminopyridine derivatives (e.g., 3-aminopyridine adenine dinucleotide) are inhibitory for H. influenzae growth. By testing characterized strains with mutations in the NAD utilization pathway, we show that 3-aminopyridine riboside is inhibitory to H. influenzae and is taken up by the NAD-processing and nicotinamide riboside route. 3-Aminopyridine riboside is utilized effectively in a pnuC+ background. In addition, we demonstrate that 3-aminopyridine adenine dinucleotide resynthesis is produced by NadR. 3-Aminopyridine riboside-resistant H. influenzae isolates were characterized, and mutations in nadR could be detected. We also tested other species of the family Pasteurellaceae, Pasteurella multocida and Actinobacillus actinomycetemcomitans, and found that 3-aminopyridine riboside does not act as a growth inhibitor; hence, 3-aminopyridine riboside represents an anti-infective agent with a very narrow host range.
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Affiliation(s)
- Elizabeta Sauer
- Institut für Hygiene und Mikrobiologie, Universität Würzburg, Würzburg, Germany
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36
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Mason KW, Zhu D, Scheuer CA, McMichael JC, Zlotnick GW, Green BA. Reduction of nasal colonization of nontypeable Haemophilus influenzae following intranasal immunization with rLP4/rLP6/UspA2 proteins combined with aqueous formulation of RC529. Vaccine 2004; 22:3449-56. [PMID: 15308371 DOI: 10.1016/j.vaccine.2004.02.027] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2003] [Revised: 02/11/2004] [Accepted: 02/12/2004] [Indexed: 10/26/2022]
Abstract
Nontypeable Haemophilus influenzae (NTHi) and Moraxella catarrhalis are common causative agents of human mucosal infections. To formulate a mucosal vaccine against these pathogens, recombinant lipidated P4 (rLP4) and P6 (rLP6) proteins of NTHi and ubiquitous cell surface protein A (UspA) of M. catarrhalis were used for active immunization experiments in a mouse nasal challenge model. BALB/c mice were immunized intranasally with these proteins formulated with a chemically synthesized adjuvant, RC529 in an aqueous formulation (RC529-AF). Three weeks after the last immunization, these animals were challenged intranasally with NTHi strain SR7332.P1 and nasal colonization measured 3 days later. To determine local and systemic immune responses, bronchoalveolar washes (BAW) and sera were collected prior to NTHi challenge. The serum and mucosal samples were analyzed by ELISA for rLP4, rLP6 and UspA2 protein-specific IgG, IgG subclass and IgA antibody titers and bactericidal titers were determined against the TTA24 and 430-345 strains of M. catarrhalis. Results of these experiments show that these proteins combined with RC529-AF administered intranasally to mice elicited (1) significantly increased rLP4/rLP6/UspA2 protein-specific circulating IgG and IgA antibody responses; (2) local rLP4/rLP6/UspA2-specific IgA responses in the respiratory tract; and (3) more than a two log reduction of nasal colonization of NTHi strain SR7332 from the nasal tissues of mice. The serum IgG subclass distribution was predominantly IgG2a, representing a Th1 response. The antiserum also exhibited bactericidal activities to several strains of M. catarrhalis. These data indicate that intranasal immunization with rLP4/rLP6/UspA2 proteins combined with RC529-AF may be able to provide a way for inducing local mucosal immunity and for prevention of otitis media in children.
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Affiliation(s)
- Kathryn W Mason
- Wyeth Vaccines Research, 401 N. Middletown Road, Pearl River, NY 10965, USA
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Yadav MC, Chakraborti A, Ray P, Sapru S, Majumdar S, Narang A. Rapid detection of Haemophilus influenzae by hel gene polymerase chain reaction. Lett Appl Microbiol 2003; 37:190-5. [PMID: 12904218 DOI: 10.1046/j.1472-765x.2003.01342.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
AIMS To evaluate the efficiency of hel gene polymerase chain reaction (PCR) to detect Haemophilus influenzae in various clinical/non-clinical samples. METHODS AND RESULTS Seventy-four clinical samples (cerebrospinal fluid, blood, sputum, throat and nasal swabs) and throat swabs of 17 asymptomatic carriers were collected. Primers were used to amplify the hel gene of H. influenzae encoding P4 outer membrane protein directly from the processed samples. The samples were also examined by conventional culture methods and the results were compared with those of PCR. The culture methods showed positive results in 60 (65.9%) of 91 samples in contrast to 62 (68.12%) samples tested positive by PCR. None of the culture-positive samples were PCR-negative while two of the culture-negative samples were PCR-positive. The specificity of the products was confirmed by Southern hybridization and failure of various other organisms to amplify the hel gene product. The sensitivity of the PCR assay was found to be 50 pg of DNA. CONCLUSIONS These findings suggest that the hel gene PCR is a rapid, sensitive and a specific new method for direct identification of H. influenzae. SIGNIFICANCE AND IMPACT OF THE STUDY Thus, this PCR test can improve the detection rate of H. influenzae in suspected clinical samples as compared with that of conventional culture methods.
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Affiliation(s)
- M C Yadav
- Department of Pediatrics, Postgraduate Institute of Medical Education and Research, Chandigarh, India
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Herbert M, Sauer E, Smethurst G, Kraiss A, Hilpert AK, Reidl J. Nicotinamide ribosyl uptake mutants in Haemophilus influenzae. Infect Immun 2003; 71:5398-401. [PMID: 12933892 PMCID: PMC187334 DOI: 10.1128/iai.71.9.5398-5401.2003] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The gene for the nicotinamide riboside (NR) transporter (pnuC) was identified in Haemophilus influenzae. A pnuC mutant had only residual NR uptake and could survive in vitro with high concentrations of NR, but could not survive in vivo. PnuC may represent a target for the development of inhibitors for preventing H. influenzae disease.
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Affiliation(s)
- Mark Herbert
- Department of Paediatrics, John Radcliffe Hospital, Headington, Oxford OX3 9DU, United Kingdom.
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39
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Andersen C, Maier E, Kemmer G, Blass J, Hilpert AK, Benz R, Reidl J. Porin OmpP2 of Haemophilus influenzae shows specificity for nicotinamide-derived nucleotide substrates. J Biol Chem 2003; 278:24269-76. [PMID: 12695515 DOI: 10.1074/jbc.m213087200] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Haemophilus influenzae has an absolute requirement for NAD (factor V) because it lacks all biosynthetic enzymes necessary for de novo synthesis of that cofactor. Therefore, growth in vitro requires the presence of NAD itself, NMN, or nicotinamide riboside (NR). To address uptake abilities of these compounds, we investigated outer membrane proteins. By analyzing ompP2 knockout mutants, we found that NAD and NMN uptake was prevented, whereas NR uptake was not. Through investigation of the properties of purified OmpP2 in artificial lipid membrane systems, the substrate specificity of OmpP2 for NAD and NMN was determined, with KS values of approximately 8 and 4mm, respectively, in 0.1 m KCl, whereas no interaction was detected for the nucleoside NR and other purine or pyrimidine nucleotide or nucleoside species. Based on our analysis, we assume that an intrinsic binding site within OmpP2 exists that facilitates diffusion of these compounds across the outer membrane, recognizing carbonyl and exposed phosphate groups. Because OmpP2 was formerly described as a general diffusion porin, an additional property of acting as a facilitator for nicotinamide-based nucleotide transport may have evolved to support and optimize utilization of the essential cofactor sources NAD and NMN in H. influenzae.
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Affiliation(s)
- Christian Andersen
- Lehrstuhl für Biotechnologie, Biozentrum der Universität Würzburg, Am Hubland, Germany
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40
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Narita SI, Kanamaru K, Matsuyama SI, Tokuda H. A mutation in the membrane subunit of an ABC transporter LolCDE complex causing outer membrane localization of lipoproteins against their inner membrane-specific signals. Mol Microbiol 2003; 49:167-77. [PMID: 12823819 DOI: 10.1046/j.1365-2958.2003.03569.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Lipoproteins in Gram-negative bacteria are anchored to the inner or outer membrane via fatty acids attached to the N-terminal cysteine. The residue at position 2 determines the membrane specificity. An ATP binding cassette transporter LolCDE complex releases lipoproteins with residues other than aspartate at position 2 from the inner membrane, whereas those with aspartate at position 2 are rejected by LolCDE and therefore remain in the inner membrane. For further understanding of this rejection mechanism, a novel strategy was developed to select mutants in which lipoproteins with aspartate at position 2 are released. The isolated mutants carried an alanine to proline mutation at position 40 of LolC, a membrane subunit of the LolCDE complex. A significant portion of an inner membrane lipoprotein, L10P(DQ), was localized to the outer membrane when the LolC mutant was expressed. Periplasmic chaperone LolA formed a complex with the released L10P(DQ), which was subsequently incorporated into the outer membrane in a LolB-dependent manner, indicating that neither LolA nor LolB rejects lipoproteins with aspartate at position 2. The amount of the LolC mutant co-purified with LolD and LolE after membrane solubilization was reduced significantly. Taken together, these results indicate that the mutation causes destabilization of the LolCDE complex and concomitantly prevents the accurate recognition of lipoprotein-sorting signals.
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Affiliation(s)
- Shin-ichiro Narita
- Institute of Molecular and Cellular Biosciences, University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-0032, Japan
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Kurnasov OV, Polanuyer BM, Ananta S, Sloutsky R, Tam A, Gerdes SY, Osterman AL. Ribosylnicotinamide kinase domain of NadR protein: identification and implications in NAD biosynthesis. J Bacteriol 2002; 184:6906-17. [PMID: 12446641 PMCID: PMC135457 DOI: 10.1128/jb.184.24.6906-6917.2002] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
NAD is an indispensable redox cofactor in all organisms. Most of the genes required for NAD biosynthesis in various species are known. Ribosylnicotinamide kinase (RNK) was among the few unknown (missing) genes involved with NAD salvage and recycling pathways. Using a comparative genome analysis involving reconstruction of NAD metabolism from genomic data, we predicted and experimentally verified that bacterial RNK is encoded within the 3' region of the nadR gene. Based on these results and previous data, the full-size multifunctional NadR protein (as in Escherichia coli) is composed of (i) an N-terminal DNA-binding domain involved in the transcriptional regulation of NAD biosynthesis, (ii) a central nicotinamide mononucleotide adenylyltransferase (NMNAT) domain, and (iii) a C-terminal RNK domain. The RNK and NMNAT enzymatic activities of recombinant NadR proteins from Salmonella enterica serovar Typhimurium and Haemophilus influenzae were quantitatively characterized. We propose a model for the complete salvage pathway from exogenous N-ribosylnicotinamide to NAD which involves the concerted action of the PnuC transporter and NRK, followed by the NMNAT activity of the NadR protein. Both the pnuC and nadR genes were proven to be essential for the growth and survival of H. influenzae, thus implicating them as potential narrow-spectrum drug targets.
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42
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Gerdes SY, Scholle MD, D'Souza M, Bernal A, Baev MV, Farrell M, Kurnasov OV, Daugherty MD, Mseeh F, Polanuyer BM, Campbell JW, Anantha S, Shatalin KY, Chowdhury SAK, Fonstein MY, Osterman AL. From genetic footprinting to antimicrobial drug targets: examples in cofactor biosynthetic pathways. J Bacteriol 2002; 184:4555-72. [PMID: 12142426 PMCID: PMC135229 DOI: 10.1128/jb.184.16.4555-4572.2002] [Citation(s) in RCA: 222] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Novel drug targets are required in order to design new defenses against antibiotic-resistant pathogens. Comparative genomics provides new opportunities for finding optimal targets among previously unexplored cellular functions, based on an understanding of related biological processes in bacterial pathogens and their hosts. We describe an integrated approach to identification and prioritization of broad-spectrum drug targets. Our strategy is based on genetic footprinting in Escherichia coli followed by metabolic context analysis of essential gene orthologs in various species. Genes required for viability of E. coli in rich medium were identified on a whole-genome scale using the genetic footprinting technique. Potential target pathways were deduced from these data and compared with a panel of representative bacterial pathogens by using metabolic reconstructions from genomic data. Conserved and indispensable functions revealed by this analysis potentially represent broad-spectrum antibacterial targets. Further target prioritization involves comparison of the corresponding pathways and individual functions between pathogens and the human host. The most promising targets are validated by direct knockouts in model pathogens. The efficacy of this approach is illustrated using examples from metabolism of adenylate cofactors NAD(P), coenzyme A, and flavin adenine dinucleotide. Several drug targets within these pathways, including three distantly related adenylyltransferases (orthologs of the E. coli genes nadD, coaD, and ribF), are discussed in detail.
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Kemmer G, Reilly TJ, Schmidt-Brauns J, Zlotnik GW, Green BA, Fiske MJ, Herbert M, Kraiss A, Schlör S, Smith A, Reidl J. NadN and e (P4) are essential for utilization of NAD and nicotinamide mononucleotide but not nicotinamide riboside in Haemophilus influenzae. J Bacteriol 2001; 183:3974-81. [PMID: 11395461 PMCID: PMC95280 DOI: 10.1128/jb.183.13.3974-3981.2001] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Haemophilus influenzae has an absolute requirement for NAD (factor V) because it lacks almost all the biosynthetic enzymes necessary for the de novo synthesis of that cofactor. Factor V can be provided as either nicotinamide adenosine dinucleotide (NAD), nicotinamide mononucleotide (NMN), or nicotinamide riboside (NR) in vitro, but little is known about the source or the mechanism of uptake of these substrates in vivo. As shown by us earlier, at least two gene products are involved in the uptake of NAD, the outer membrane lipoprotein e (P4), which has phosphatase activity and is encoded by hel, and a periplasmic NAD nucleotidase, encoded by nadN. It has also been observed that the latter gene product is essential for H. influenzae growth on media supplemented with NAD. In this report, we describe the functions and substrates of these two proteins as they act together in an NAD utilization pathway. Data are provided which indicate that NadN harbors not only NAD pyrophosphatase but also NMN 5'-nucleotidase activity. The e (P4) protein is also shown to have NMN 5'-nucleotidase activity, recognizing NMN as a substrate and releasing NR as its product. Insertion mutants of nadN or deletion and site-directed mutants of hel had attenuated growth and a reduced uptake phenotype when NMN served as substrate. A hel and nadN double mutant was only able to grow in the presence of NR, whereas no uptake of NMN was observed.
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Affiliation(s)
- G Kemmer
- Zentrum für Infektionsforschung, Universität Würzburg, 97070 Würzburg, Germany
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Hartmann E, Lingwood CA, Reidl J. Heat-inducible surface stress protein (Hsp70) mediates sulfatide recognition of the respiratory pathogen Haemophilus influenzae. Infect Immun 2001; 69:3438-41. [PMID: 11292771 PMCID: PMC98307 DOI: 10.1128/iai.69.5.3438-3441.2001] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The in vitro glycolipid binding specificity of clinical strains of nontypeable Haemophilus influenzae is altered to include sulfated glycolipids following a brief heat shock. We have constructed, expressed, and purified a recombinant protein of H. influenzae Hsp70, which showed significant specific binding to sulfated galactolipids in vitro. Furthermore, indirect immunofluorescence demonstrates that Hsp70 proteins are surface exposed in H. influenzae only after heat shock and are contained in the outer membrane protein fractions.
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Affiliation(s)
- E Hartmann
- Zentrum für Infektionsforschung, Universität Würzburg, Röntgenring 11, Würzburg, Germany.
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Reilly TJ, Green BA, Zlotnick GW, Smith AL. Contribution of the DDDD motif of H. influenzae e (P4) to phosphomonoesterase activity and heme transport. FEBS Lett 2001; 494:19-23. [PMID: 11297727 DOI: 10.1016/s0014-5793(01)02294-3] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Haemophilus influenzae lipoprotein e (P4) is a member of the DDDD phosphohydrolase superfamily and mediates heme transport. Each of the aspartate residues of the signature motif is required for phosphomonoesterase activity, as none of the e (P4) single D mutants (D64A, D66A, D181N, and D185A) possessed detectable phosphomonoesterase activity. These results suggest that the signature motif is essential to the phosphomonoesterase activity of lipoprotein e (P4). When assessed for phosphomonoesterase-dependent heme transport activity in Escherichia coli hemA strains, plasmids containing D181N and D185A retained heme transport as indicated by aerobic growth while D64A and D66A did not. We conclude that phosphomonoesterase activity is not required for heme transport.
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Affiliation(s)
- T J Reilly
- Department of Molecular Microbiology and Imunology, University of Missouri Medical School, Columbia, MO 65212, USA
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