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Vassallo N. Poration of mitochondrial membranes by amyloidogenic peptides and other biological toxins. J Neurochem 2024. [PMID: 39213385 DOI: 10.1111/jnc.16213] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2024] [Revised: 08/09/2024] [Accepted: 08/12/2024] [Indexed: 09/04/2024]
Abstract
Mitochondria are essential organelles known to serve broad functions, including in cellular metabolism, calcium buffering, signaling pathways and the regulation of apoptotic cell death. Maintaining the integrity of the outer (OMM) and inner mitochondrial membranes (IMM) is vital for mitochondrial health. Cardiolipin (CL), a unique dimeric glycerophospholipid, is the signature lipid of energy-converting membranes. It plays a significant role in maintaining mitochondrial architecture and function, stabilizing protein complexes and facilitating efficient oxidative phosphorylation (OXPHOS) whilst regulating cytochrome c release from mitochondria. CL is especially enriched in the IMM and at sites of contact between the OMM and IMM. Disorders of protein misfolding, such as Alzheimer's and Parkinson's diseases, involve amyloidogenic peptides like amyloid-β, tau and α-synuclein, which form metastable toxic oligomeric species that interact with biological membranes. Electrophysiological studies have shown that these oligomers form ion-conducting nanopores in membranes mimicking the IMM's phospholipid composition. Poration of mitochondrial membranes disrupts the ionic balance, causing osmotic swelling, loss of the voltage potential across the IMM, release of pro-apoptogenic factors, and leads to cell death. The interaction between CL and amyloid oligomers appears to favour their membrane insertion and pore formation, directly implicating CL in amyloid toxicity. Additionally, pore formation in mitochondrial membranes is not limited to amyloid proteins and peptides; other biological peptides, as diverse as the pro-apoptotic Bcl-2 family members, gasdermin proteins, cobra venom cardiotoxins and bacterial pathogenic toxins, have all been described to punch holes in mitochondria, contributing to cell death processes. Collectively, these findings underscore the vulnerability of mitochondria and the involvement of CL in various pathogenic mechanisms, emphasizing the need for further research on targeting CL-amyloid interactions to mitigate mitochondrial dysfunction.
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Affiliation(s)
- Neville Vassallo
- Department of Physiology and Biochemistry, Faculty of Medicine and Surgery, University of Malta, Tal-Qroqq, Malta
- Centre for Molecular Medicine and Biobanking, University of Malta, Tal-Qroqq, Malta
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2
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Persson A, Koivula T, Jacobsson S, Stenmark B. Diverse proinflammatory response in pharyngeal epithelial cells upon interaction with Neisseria meningitidis carriage and invasive isolates. BMC Infect Dis 2024; 24:286. [PMID: 38443838 PMCID: PMC10916014 DOI: 10.1186/s12879-024-09186-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2023] [Accepted: 03/01/2024] [Indexed: 03/07/2024] Open
Abstract
BACKGROUND Invasive meningococcal disease (IMD), including sepsis and meningitis, can develop when Neisseria meningitidis bacteria breach the barrier and gain access to the circulation. While IMD is a rare outcome of bacterial exposure, colonization of the oropharynx is present in approximately 10% of the human population. This asymptomatic carriage can be long or short term, and it is unknown which determining factors regulate bacterial colonization. Despite descriptions of many bacterial virulence factors and recent advances in detailed genetic identification and characterization of bacteria, the factors mediating invasion and disease vs. asymptomatic carriage following bacterial colonization remain unknown. The pharyngeal epithelia play a role in the innate immune defense against pathogens, and the aim of this study was to investigate the proinflammatory response of pharyngeal epithelial cells following meningococcal exposure to describe the potential inflammatory mediation performed during the initial host‒pathogen interaction. Clinically relevant isolates of serogroups B, C, W and Y, derived from patients with meningococcal disease as well as asymptomatic carriers, were included in the study. RESULTS The most potent cellular response with proinflammatory secretion of TNF, IL-6, CXCL8, CCL2, IL-1β and IL-18 was found in response to invasive serogroup B isolates. This potent response pattern was also mirrored by increased bacterial adhesion to cells as well as induced cell death. It was, however, only with serogroup B isolates where the most potent cellular response was toward the IMD isolates. In contrast, the most potent cellular response using serogroup Y isolates was directed toward the carriage isolates rather than the IMD isolates. In addition, by comparing isolates from outbreaks in Sweden (epidemiologically linked and highly genetically similar), we found the most potent proinflammatory response in cells exposed to carriage isolates rather than the IMD isolates. CONCLUSION Although certain expected correlations between host‒pathogen interactions and cellular proinflammatory responses were found using IMD serogroup B isolates, our data indicate that carriage isolates invoke stronger proinflammatory activation of the epithelial lining than IMD isolates.
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Affiliation(s)
- Alexander Persson
- School of Medical Sciences, Faculty of Medicine and Health, Örebro University, Örebro, Sweden.
- Inflammatory Response and Infection Susceptibility Centre (iRiSC), Faculty of Medicine and Health, Örebro University, Örebro, Sweden.
| | - Therese Koivula
- School of Medical Sciences, Faculty of Medicine and Health, Örebro University, Örebro, Sweden
- Inflammatory Response and Infection Susceptibility Centre (iRiSC), Faculty of Medicine and Health, Örebro University, Örebro, Sweden
| | - Susanne Jacobsson
- Department of Laboratory Medicine, Faculty of Medicine and Health, Örebro University, Örebro, Sweden
| | - Bianca Stenmark
- Department of Laboratory Medicine, Faculty of Medicine and Health, Örebro University, Örebro, Sweden
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Sajeevan A, Ramamurthy T, Solomon AP. Vibrio cholerae virulence and its suppression through the quorum-sensing system. Crit Rev Microbiol 2024:1-22. [PMID: 38441045 DOI: 10.1080/1040841x.2024.2320823] [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: 07/30/2023] [Accepted: 02/10/2024] [Indexed: 03/06/2024]
Abstract
Vibrio cholerae is a cholera-causing pathogen known to instigate severe contagious diarrhea that affects millions globally. Survival of vibrios depend on a combination of multicellular responses and adapt to changes that prevail in the environment. This process is achieved through a strong communication at the cellular level, the process has been recognized as quorum sensing (QS). The severity of infection is highly dependent on the QS of vibrios in the gut milieu. The quorum may exist in a low/high cell density (LCD/HCD) state to exert a positive or negative response to control the regulatory pathogenic networks. The impact of this regulation reflects on the transition of pathogenic V. cholerae from the environment to infect humans and cause outbreaks or epidemics of cholera. In this context, the review portrays various regulatory processes and associated virulent pathways, which maneuver and control LCD and HCD states for their survival in the host. Although several treatment options are existing, promotion of therapeutics by exploiting the virulence network may potentiate ineffective antibiotics to manage cholera. In addition, this approach is also useful in resource-limited settings, where the accessibility to antibiotics or conventional therapeutic options is limited.
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Affiliation(s)
- Anusree Sajeevan
- Quorum Sensing Laboratory, Centre for Research in Infectious Diseases (CRID), School of Chemical and Biotechnology, SASTRA Deemed to be University, Thanjavur, India
| | - Thandavarayan Ramamurthy
- Division of Bacteriology, ICMR-National Institute of Cholera and Enteric Disease, Kolkata, India
| | - Adline Princy Solomon
- Quorum Sensing Laboratory, Centre for Research in Infectious Diseases (CRID), School of Chemical and Biotechnology, SASTRA Deemed to be University, Thanjavur, India
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Ball LM, Bronstein E, Liechti GW, Maurelli AT. Neisseria gonorrhoeae drives Chlamydia trachomatis into a persistence-like state during in vitro co-infection. Infect Immun 2024; 92:e0017923. [PMID: 38014981 PMCID: PMC10790821 DOI: 10.1128/iai.00179-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Accepted: 11/05/2023] [Indexed: 11/29/2023] Open
Abstract
Chlamydia trachomatis and Neisseria gonorrhoeae are the most prevalent bacterial sexually transmitted infections (STIs) globally. Despite frequent co-infections in patients, few studies have investigated how mono-infections may differ from co-infections. We hypothesized that a symbiotic relationship between the pathogens could account for the high rates of clinical co-infection. During in vitro co-infection, we observed an unexpected phenotype where the C. trachomatis developmental cycle was impaired by N. gonorrhoeae. C. trachomatis is an obligate intracellular pathogen with a unique biphasic developmental cycle progressing from infectious elementary bodies (EB) to replicative reticulate bodies (RB), and back. After 12 hours of co-infection, we observed fewer EBs than in a mono-infection. Chlamydial genome copy number remained equivalent between mono- and co-infections. This is a hallmark of Chlamydial persistence. Chlamydial persistence alters inclusion morphology but varies depending on the stimulus/stress. We observed larger, but fewer, Chlamydia during co-infection. Tryptophan depletion can induce Chlamydial persistence, but tryptophan supplementation did not reverse the co-infection phenotype. Only viable and actively growing N. gonorrhoeae produced the inhibition phenotype in C. trachomatis. Piliated N. gonorrhoeae had the strongest effect on C. trachomatis, but hyperpiliated or non-piliated N. gonorrhoeae still produced the phenotype. EB development was modestly impaired when N. gonorrhoeae were grown in transwells above the infected monolayer. C. trachomatis serovar L2 was not impaired during co-infection. Chlamydial impairment could be due to cytoskeletal or osmotic stress caused by an as-yet-undefined mechanism. We conclude that N. gonorrhoeae induces a persistence-like state in C. trachomatis that is serovar dependent.
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Affiliation(s)
- Louise M. Ball
- Emerging Pathogens Institute and Department of Environmental and Global Health, College of Public Health and Health Professions, University of Florida, Gainesville, Florida, USA
| | - Ellis Bronstein
- F. Edward Hébert School of Medicine, Uniformed Services University, Bethesda, Maryland, USA
| | - George W. Liechti
- Department of Microbiology and Immunology, F. Edward Hébert School of Medicine, Uniformed Services University, Bethesda, Maryland, USA
| | - Anthony T. Maurelli
- Emerging Pathogens Institute and Department of Environmental and Global Health, College of Public Health and Health Professions, University of Florida, Gainesville, Florida, USA
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François-Étienne S, Nicolas L, Eric N, Jaqueline C, Pierre-Luc M, Sidki B, Aleicia H, Danilo B, Luis VA, Nicolas D. Important role of endogenous microbial symbionts of fish gills in the challenging but highly biodiverse Amazonian blackwaters. Nat Commun 2023; 14:3903. [PMID: 37414754 PMCID: PMC10326040 DOI: 10.1038/s41467-023-39461-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Accepted: 06/09/2023] [Indexed: 07/08/2023] Open
Abstract
Amazonian blackwaters are extremely biodiverse systems containing some of Earth's most naturally acidic, dissolved organic carbon -rich and ion-poor waters. Physiological adaptations of fish facing these ionoregulatory challenges are unresolved but could involve microbially-mediated processes. Here, we characterize the physiological response of 964 fish-microbe systems from four blackwater Teleost species along a natural hydrochemical gradient, using dual RNA-Seq and 16 S rRNA of gill samples. We find that host transcriptional responses to blackwaters are species-specific, but occasionally include the overexpression of Toll-receptors and integrins associated to interkingdom communication. Blackwater gill microbiomes are characterized by a transcriptionally-active betaproteobacterial cluster potentially interfering with epithelial permeability. We explore further blackwater fish-microbe interactions by analyzing transcriptomes of axenic zebrafish larvae exposed to sterile, non-sterile and inverted (non-native bacterioplankton) blackwater. We find that axenic zebrafish survive poorly when exposed to sterile/inverted blackwater. Overall, our results suggest a critical role for endogenous symbionts in blackwater fish physiology.
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Affiliation(s)
- Sylvain François-Étienne
- Institut de Biologie Intégrative et des Systèmes, Université Laval, 1030 avenue de la Médecine, Québec (QC), G1V 0A6, Canada.
- Fisheries and Oceans, Gulf Fisheries Center, 343 University Ave, Moncton, NB, E1C 5K4, Canada.
| | - Leroux Nicolas
- Institut de Biologie Intégrative et des Systèmes, Université Laval, 1030 avenue de la Médecine, Québec (QC), G1V 0A6, Canada
| | - Normandeau Eric
- Institut de Biologie Intégrative et des Systèmes, Université Laval, 1030 avenue de la Médecine, Québec (QC), G1V 0A6, Canada
| | - Custodio Jaqueline
- Instituto Nacional de Pesquisas da Amazônia (INPA), Laboratório de Ecofisiologia e Evolução Molecular, Manaus, AM, 69067-375, Brazil
| | - Mercier Pierre-Luc
- Institut de Biologie Intégrative et des Systèmes, Université Laval, 1030 avenue de la Médecine, Québec (QC), G1V 0A6, Canada
| | - Bouslama Sidki
- Institut de Biologie Intégrative et des Systèmes, Université Laval, 1030 avenue de la Médecine, Québec (QC), G1V 0A6, Canada
| | - Holland Aleicia
- La Trobe University, School of Agriculture, Biomedicine and Environment, Department of Environment and Genetics, Centre for Freshwater Ecosystems, Albury/Wodonga Campus, Vic, Australia
| | - Barroso Danilo
- Instituto Nacional de Pesquisas da Amazônia (INPA), Laboratório de Ecofisiologia e Evolução Molecular, Manaus, AM, 69067-375, Brazil
| | - Val Adalberto Luis
- Instituto Nacional de Pesquisas da Amazônia (INPA), Laboratório de Ecofisiologia e Evolução Molecular, Manaus, AM, 69067-375, Brazil
| | - Derome Nicolas
- Institut de Biologie Intégrative et des Systèmes, Université Laval, 1030 avenue de la Médecine, Québec (QC), G1V 0A6, Canada
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Wanford JJ, Odendall C. Ca 2+-calmodulin signalling at the host-pathogen interface. Curr Opin Microbiol 2023; 72:102267. [PMID: 36716574 DOI: 10.1016/j.mib.2023.102267] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2022] [Revised: 12/19/2022] [Accepted: 01/04/2023] [Indexed: 01/29/2023]
Abstract
Multiple eukaryotic cell processes are modulated by calcium ions (Ca2+). As such, Ca2+ is emerging as a crucial regulator of innate immunity in multicellular organisms. In particular, recent studies have identified roles of Ca2+ signalling at the host-bacteria interface. Following microbial exposure, Ca2+ signals mobilised from the extracellular milieu or intracellular stores are transduced into cell physiological responses. However, during infection with host-adapted pathogens, Ca2+ signals are often atypical, due to the activities of virulence factors, with varied consequences for both the pathogen and the host cell. In this review, we describe the Ca2+-dependent host factors regulating antibacterial immunity, in addition to bacterial effectors that promote, inhibit, or co-opt Ca2+-calmodulin signalling to promote infection.
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Affiliation(s)
- Joseph J Wanford
- School of Immunology and Microbial Sciences, Kings College London, London, UK
| | - Charlotte Odendall
- School of Immunology and Microbial Sciences, Kings College London, London, UK.
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Walker E, van Niekerk S, Hanning K, Kelton W, Hicks J. Mechanisms of host manipulation by Neisseria gonorrhoeae. Front Microbiol 2023; 14:1119834. [PMID: 36819065 PMCID: PMC9935845 DOI: 10.3389/fmicb.2023.1119834] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Accepted: 01/18/2023] [Indexed: 02/05/2023] Open
Abstract
Neisseria gonorrhoeae (also known as gonococcus) has been causing gonorrhoea in humans since ancient Egyptian times. Today, global gonorrhoea infections are rising at an alarming rate, in concert with an increasing number of antimicrobial-resistant strains. The gonococcus has concurrently evolved several intricate mechanisms that promote pathogenesis by evading both host immunity and defeating common therapeutic interventions. Central to these adaptations is the ability of the gonococcus to manipulate various host microenvironments upon infection. For example, the gonococcus can survive within neutrophils through direct regulation of both the oxidative burst response and maturation of the phagosome; a concerning trait given the important role neutrophils have in defending against invading pathogens. Hence, a detailed understanding of how N. gonorrhoeae exploits the human host to establish and maintain infection is crucial for combating this pathogen. This review summarizes the mechanisms behind host manipulation, with a central focus on the exploitation of host epithelial cell signaling to promote colonization and invasion of the epithelial lining, the modulation of the host immune response to evade both innate and adaptive defenses, and the manipulation of host cell death pathways to both assist colonization and combat antimicrobial activities of innate immune cells. Collectively, these pathways act in concert to enable N. gonorrhoeae to colonize and invade a wide array of host tissues, both establishing and disseminating gonococcal infection.
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Affiliation(s)
- Emma Walker
- Te Huataki Waiora, School of Health, University of Waikato, Hamilton, New Zealand
| | - Stacy van Niekerk
- Te Huataki Waiora, School of Health, University of Waikato, Hamilton, New Zealand
| | - Kyrin Hanning
- Te Huataki Waiora, School of Health, University of Waikato, Hamilton, New Zealand
| | - William Kelton
- Te Huataki Waiora, School of Health, University of Waikato, Hamilton, New Zealand
- Te Aka Mātuatua School of Science, University of Waikato, Hamilton, New Zealand
| | - Joanna Hicks
- Te Huataki Waiora, School of Health, University of Waikato, Hamilton, New Zealand
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8
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Portnyagina OY, Ivashkevich DN, Duizen IV, Shevchenko LS, Novikova OD. Effect of Non-Specific Porins from the Outer Membrane of Yersinia pseudotuberculosis on Mice Brain Cortex Tissues. BIOCHEMISTRY (MOSCOW) 2023; 88:142-151. [PMID: 37068878 DOI: 10.1134/s0006297923010121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
It was found that a single-dose immunization of mice with Yersinia pseudotuberculosis porins OmpF and OmpC causes development of pathological changes in the deep layers of cerebral cortex characterized by dystrophic changes in the cells against the background of the increasing titer of specific antibodies. At the same time, the increased level of caspase-3 expression is observed in the neurons, which indicates induction of proapoptotic signaling pathways. The obtained results indicate potential ability of nonspecific pore-forming proteins of the outer membrane of Gram-negative bacteria to initiate development of degenerative changes in brain cells.
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Affiliation(s)
- Olga Yu Portnyagina
- G. B. Elyakov Pacific Institute of Bioorganic Chemistry, Far East Branch, Russian Academy of Sciences, Vladivostok, 690021, Russia.
| | - Darya N Ivashkevich
- A. V. Zhirmunsky National Scientific Center of Marine Biology, Far Eastern Branch, Russian Academy of Sciences, Vladivostok, 690041, Russia
| | - Inessa V Duizen
- A. V. Zhirmunsky National Scientific Center of Marine Biology, Far Eastern Branch, Russian Academy of Sciences, Vladivostok, 690041, Russia
| | - Ludmila S Shevchenko
- G. B. Elyakov Pacific Institute of Bioorganic Chemistry, Far East Branch, Russian Academy of Sciences, Vladivostok, 690021, Russia
| | - Olga D Novikova
- G. B. Elyakov Pacific Institute of Bioorganic Chemistry, Far East Branch, Russian Academy of Sciences, Vladivostok, 690021, Russia
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Mahmud SA, Qureshi MA, Pellegrino MW. On the offense and defense: mitochondrial recovery programs amidst targeted pathogenic assault. FEBS J 2022; 289:7014-7037. [PMID: 34270874 PMCID: PMC9192128 DOI: 10.1111/febs.16126] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 06/24/2021] [Accepted: 07/15/2021] [Indexed: 01/13/2023]
Abstract
Bacterial pathogens employ a variety of tactics to persist in their host and promote infection. Pathogens often target host organelles in order to benefit their survival, either through manipulation or subversion of their function. Mitochondria are regularly targeted by bacterial pathogens owing to their diverse cellular roles, including energy production and regulation of programmed cell death. However, disruption of normal mitochondrial function during infection can be detrimental to cell viability because of their essential nature. In response, cells use multiple quality control programs to mitigate mitochondrial dysfunction and promote recovery. In this review, we will provide an overview of mitochondrial recovery programs including mitochondrial dynamics, the mitochondrial unfolded protein response (UPRmt ), and mitophagy. We will then discuss the various approaches used by bacterial pathogens to target mitochondria, which result in mitochondrial dysfunction. Lastly, we will discuss how cells leverage mitochondrial recovery programs beyond their role in organelle repair, to promote host defense against pathogen infection.
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Affiliation(s)
- Siraje A Mahmud
- Department of Biology, University of Texas Arlington, TX, USA
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Onorini D, Borel N, Schoborg RV, Leonard CA. Neisseria gonorrhoeae Limits Chlamydia trachomatis Inclusion Development and Infectivity in a Novel In Vitro Co-Infection Model. Front Cell Infect Microbiol 2022; 12:911818. [PMID: 35873141 PMCID: PMC9300984 DOI: 10.3389/fcimb.2022.911818] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2022] [Accepted: 06/14/2022] [Indexed: 11/13/2022] Open
Abstract
Chlamydia trachomatis (Ct) and Neisseria gonorrhoeae (Ng) are the most common bacterial sexually transmitted infections (STIs) worldwide. The primary site of infection for both bacteria is the epithelium of the endocervix in women and the urethra in men; both can also infect the rectum, pharynx and conjunctiva. Ct/Ng co-infections are more common than expected by chance, suggesting Ct/Ng interactions increase susceptibility and/or transmissibility. To date, studies have largely focused on each pathogen individually and models exploring co-infection are limited. We aimed to determine if Ng co-infection influences chlamydial infection and development and we hypothesized that Ng-infected cells are more susceptible to chlamydial infection than uninfected cells. To address this hypothesis, we established an in vitro model of Ct/Ng co-infection in cultured human cervical epithelial cells. Our data show that Ng co-infection elicits an anti-chlamydial effect by reducing chlamydial infection, inclusion size, and subsequent infectivity. Notably, the anti-chlamydial effect is dependent on Ng viability but not extracellular nutrient depletion or pH modulation. Though this finding is not consistent with our hypothesis, it provides evidence that interaction of these bacteria in vitro influences chlamydial infection and development. This Ct/Ng co-infection model, established in an epithelial cell line, will facilitate further exploration into the pathogenic interplay between Ct and Ng.
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Affiliation(s)
- Delia Onorini
- Institute of Veterinary Pathology, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland
| | - Nicole Borel
- Institute of Veterinary Pathology, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland
| | - Robert V. Schoborg
- Department of Medical Education, Center for Infectious Disease, Inflammation and Immunity, Quillen College of Medicine, East Tennessee State University, Johnson City, TN, United States
| | - Cory Ann Leonard
- Institute of Veterinary Pathology, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland
- *Correspondence: Cory Ann Leonard,
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Aboud S, Buhalata SN, Onduru OG, Chiduo MG, Kwesigabo GP, Mshana SE, Manjurano AM, Temu MM, Kishamawe C, Changalucha JM. Antimicrobial Susceptibility Testing Patterns of Neisseria gonorrhoeae from Patients Attending Sexually Transmitted Infections Clinics in Six Regions in Tanzania. Trop Med Infect Dis 2022; 7:tropicalmed7060089. [PMID: 35736968 PMCID: PMC9231259 DOI: 10.3390/tropicalmed7060089] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2022] [Revised: 05/25/2022] [Accepted: 05/28/2022] [Indexed: 11/30/2022] Open
Abstract
Antimicrobial resistance (AMR) is global health threat that is on the increase, and it has been adversely affecting the proper management of sexually transmitted infections (STI). Data on antimicrobial susceptibility testing patterns of N. gonorrhoeae are limited in local settings. We determined in vitro antimicrobial susceptibility and phenotypic profiles of N. gonorrhoeae isolated from STI/Outpatient Department (OPD) clinics. Minimum Inhibitory Concentrations (MIC) (µg/mL) were determined using E-Test and agar dilution methods for previously and currently recommended antimicrobial agents. A total of 164 N. gonorrhoeae isolates from urethral discharge and endocervical swabs were tested. The prevalence of resistant N. gonorrhoeae to tetracycline, norfloxacin, penicillin and ciprofloxacin were 98.6%, 82.2%, 84.3% and 75.6%, respectively. None of the isolates was resistant to kanamycin. Penicillinase producing N. gonorrhoeae (PPNG) was found to be 73.7%, with 56.7% and 43.3% observed among isolates from women and men, respectively. Tetracycline resistant-N. gonorrhoeae (TRNG) was found to be 34.0%, and QRNG with HLR to ciprofloxacin was 79.9%. The overall MDR-NG was 79.9%, and XDR-NG was 3.6%. MIC50 and MIC90 were 4.0 and 8.0 and 2.0 and 4.0 µg/mL for ciprofloxacin and norfloxacin, respectively. Dendrograms showed that 44 phenotypic groups are associated with a high rate of AMR among high MDR-NG and moderate XDR-NG isolates. The predominant groups of quinolone-resistant N. gonorrhoeae (QRNG)+PPNG (34.7%) and QRNG+PPNG+TRNG (32.9%) were observed among the isolates having HLR to ciprofloxacin. We reported a high prevalence of AMR (>90%) to previously recommended antimicrobials used for the treatment of gonorrhoea. Multidrug resistant N. gonorrhoeae (MDR-NG) was highly reported, and extensively drug resistant (XDR-NG) has gradually increased to the currently recommended cephalosporins including ceftriaxone and cefixime. Heterogeneous groups of QRNG+PPNG+ and QRNG+PPNG+TRNG were highly resistant to penicillin, tetracycline, ciprofloxacin and norfloxacin. A surveillance program is imperative in the country to curb the spread of AMR.
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Affiliation(s)
- Said Aboud
- Departments of Microbiology and Immunology, Epidemiology and Biostatistics, Muhimbili University of Health and Allied Sciences (MUHAS), Dar es Salaam P.O. Box 65001, Tanzania; (S.N.B.); (G.P.K.)
- Correspondence:
| | - Simon N. Buhalata
- Departments of Microbiology and Immunology, Epidemiology and Biostatistics, Muhimbili University of Health and Allied Sciences (MUHAS), Dar es Salaam P.O. Box 65001, Tanzania; (S.N.B.); (G.P.K.)
- National Institute for Medical Research, Mwanza Research Centre, Mwanza P.O. Box 1462, Tanzania; (A.M.M.); (M.M.T.); (C.K.); (J.M.C.)
| | - Onduru G. Onduru
- Department of Pathology, College of Medicine, Kamuzu University of Health Sciences, Blantyre P.O. Box 360, Malawi;
| | - Mercy G. Chiduo
- National Institute for Medical Research, Tanga Research Centre, Tanga P.O. Box 5004, Tanzania;
| | - Gideon P. Kwesigabo
- Departments of Microbiology and Immunology, Epidemiology and Biostatistics, Muhimbili University of Health and Allied Sciences (MUHAS), Dar es Salaam P.O. Box 65001, Tanzania; (S.N.B.); (G.P.K.)
| | - Stephen E. Mshana
- Department of Medical Microbiology, Catholic University of Health and Allied Sciences (CUHAS), Mwanza P.O. Box 1370, Tanzania;
| | - Alphaxard M. Manjurano
- National Institute for Medical Research, Mwanza Research Centre, Mwanza P.O. Box 1462, Tanzania; (A.M.M.); (M.M.T.); (C.K.); (J.M.C.)
| | - Mansuet M. Temu
- National Institute for Medical Research, Mwanza Research Centre, Mwanza P.O. Box 1462, Tanzania; (A.M.M.); (M.M.T.); (C.K.); (J.M.C.)
| | - Coleman Kishamawe
- National Institute for Medical Research, Mwanza Research Centre, Mwanza P.O. Box 1462, Tanzania; (A.M.M.); (M.M.T.); (C.K.); (J.M.C.)
| | - John M. Changalucha
- National Institute for Medical Research, Mwanza Research Centre, Mwanza P.O. Box 1462, Tanzania; (A.M.M.); (M.M.T.); (C.K.); (J.M.C.)
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Kayastha BB, Kubo A, Burch-Konda J, Dohmen RL, McCoy JL, Rogers RR, Mares S, Bevere J, Huckaby A, Witt W, Peng S, Chaudhary B, Mohanty S, Barbier M, Cook G, Deng J, Patrauchan MA. EF-hand protein, EfhP, specifically binds Ca 2+ and mediates Ca 2+ regulation of virulence in a human pathogen Pseudomonas aeruginosa. Sci Rep 2022; 12:8791. [PMID: 35614085 PMCID: PMC9132961 DOI: 10.1038/s41598-022-12584-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2022] [Accepted: 05/09/2022] [Indexed: 11/30/2022] Open
Abstract
Calcium (Ca2+) is well known as a second messenger in eukaryotes, where Ca2+ signaling controls life-sustaining cellular processes. Although bacteria produce the components required for Ca2+ signaling, little is known about the mechanisms of bacterial Ca2+ signaling. Previously, we have identified a putative Ca2+-binding protein EfhP (PA4107) with two canonical EF-hand motifs and reported that EfhP mediates Ca2+ regulation of virulence factors production and infectivity in Pseudomonas aeruginosa, a human pathogen causing life-threatening infections. Here, we show that EfhP selectively binds Ca2+ with 13.7 µM affinity, and that mutations at the +X and -Z positions within each or both EF-hand motifs abolished Ca2+ binding. We also show that the hydrophobicity of EfhP increased in a Ca2+-dependent manner, however no such response was detected in the mutated proteins. 15 N-NMR showed Ca2+-dependent chemical shifts in EfhP confirming Ca2+-binding triggered structural rearrangements in the protein. Deletion of efhP impaired P. aeruginosa survival in macrophages and virulence in vivo. Disabling EfhP Ca2+ binding abolished Ca2+ induction of pyocyanin production in vitro. These data confirm that EfhP selectively binds Ca2+, which triggers its structural changes required for the Ca2+ regulation of P. aeruginosa virulence, thus establishing the role of EfhP as a Ca2+ sensor.
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Affiliation(s)
- Biraj B Kayastha
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, OK, 74078, USA
| | - Aya Kubo
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, OK, 74078, USA
| | - Jacob Burch-Konda
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, OK, 74078, USA
| | - Rosalie L Dohmen
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, OK, 74078, USA
| | - Jacee L McCoy
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, OK, 74078, USA
| | - Rendi R Rogers
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, OK, 74078, USA
| | - Sergio Mares
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, OK, 74078, USA
| | - Justin Bevere
- Vaccine Development Center at West Virginia University, Morgantown, WV, 26506, USA
- Department of Microbiology, Immunology and Cell Biology, West Virginia University, Morgantown, WV, 26506, USA
| | - Annalisa Huckaby
- Vaccine Development Center at West Virginia University, Morgantown, WV, 26506, USA
- Department of Microbiology, Immunology and Cell Biology, West Virginia University, Morgantown, WV, 26506, USA
| | - William Witt
- Vaccine Development Center at West Virginia University, Morgantown, WV, 26506, USA
- Department of Microbiology, Immunology and Cell Biology, West Virginia University, Morgantown, WV, 26506, USA
| | - Shuxia Peng
- Department of Biochemistry and Molecular Biology, Oklahoma State University, Stillwater, OK, 74078, USA
| | - Bharat Chaudhary
- Department of Chemistry, Oklahoma State University, Stillwater, OK, 74078, USA
| | - Smita Mohanty
- Department of Chemistry, Oklahoma State University, Stillwater, OK, 74078, USA
| | - Mariette Barbier
- Vaccine Development Center at West Virginia University, Morgantown, WV, 26506, USA
- Department of Microbiology, Immunology and Cell Biology, West Virginia University, Morgantown, WV, 26506, USA
| | - Gabriel Cook
- Department of Chemistry, Oklahoma State University, Stillwater, OK, 74078, USA
| | - Junpeng Deng
- Department of Biochemistry and Molecular Biology, Oklahoma State University, Stillwater, OK, 74078, USA
| | - Marianna A Patrauchan
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, OK, 74078, USA.
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13
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Ferrell KC, Johansen MD, Triccas JA, Counoupas C. Virulence Mechanisms of Mycobacterium abscessus: Current Knowledge and Implications for Vaccine Design. Front Microbiol 2022; 13:842017. [PMID: 35308378 PMCID: PMC8928063 DOI: 10.3389/fmicb.2022.842017] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Accepted: 02/08/2022] [Indexed: 12/22/2022] Open
Abstract
Mycobacterium abscessus is a member of the non-tuberculous mycobacteria (NTM) group, responsible for chronic infections in individuals with cystic fibrosis (CF) or those otherwise immunocompromised. While viewed traditionally as an opportunistic pathogen, increasing research into M. abscessus in recent years has highlighted its continued evolution into a true pathogen. This is demonstrated through an extensive collection of virulence factors (VFs) possessed by this organism which facilitate survival within the host, particularly in the harsh environment of the CF lung. These include VFs resembling those of other Mycobacteria, and non-mycobacterial VFs, both of which make a notable contribution in shaping M. abscessus interaction with the host. Mycobacterium abscessus continued acquisition of VFs is cause for concern and highlights the need for novel vaccination strategies to combat this pathogen. An effective M. abscessus vaccine must be suitably designed for target populations (i.e., individuals with CF) and incorporate current knowledge on immune correlates of protection against M. abscessus infection. Vaccination strategies must also build upon lessons learned from ongoing efforts to develop novel vaccines for other pathogens, particularly Mycobacterium tuberculosis (M. tb); decades of research into M. tb has provided insight into unconventional and innovative vaccine approaches that may be applied to M. abscessus. Continued research into M. abscessus pathogenesis will be critical for the future development of safe and effective vaccines and therapeutics to reduce global incidence of this emerging pathogen.
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Affiliation(s)
- Kia C. Ferrell
- School of Medical Sciences, Faculty of Medicine and Health, The University of Sydney, Camperdown, NSW, Australia
- Tuberculosis Research Program, Centenary Institute, Sydney, NSW, Australia
- *Correspondence: Kia C. Ferrell,
| | - Matt D. Johansen
- Centre for Inflammation, Centenary Institute, University of Technology, Sydney, NSW, Australia
- Faculty of Science, School of Life Sciences, University of Technology, Sydney, NSW, Australia
| | - James A. Triccas
- School of Medical Sciences, Faculty of Medicine and Health, The University of Sydney, Camperdown, NSW, Australia
- Sydney Institute for Infectious Diseases and the Charles Perkins Centre, The University of Sydney, Camperdown, NSW, Australia
| | - Claudio Counoupas
- School of Medical Sciences, Faculty of Medicine and Health, The University of Sydney, Camperdown, NSW, Australia
- Tuberculosis Research Program, Centenary Institute, Sydney, NSW, Australia
- Sydney Institute for Infectious Diseases and the Charles Perkins Centre, The University of Sydney, Camperdown, NSW, Australia
- Claudio Counoupas,
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14
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Farmen K, Tofiño-Vian M, Iovino F. Neuronal Damage and Neuroinflammation, a Bridge Between Bacterial Meningitis and Neurodegenerative Diseases. Front Cell Neurosci 2021; 15:680858. [PMID: 34149363 PMCID: PMC8209290 DOI: 10.3389/fncel.2021.680858] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Accepted: 05/03/2021] [Indexed: 12/13/2022] Open
Abstract
Bacterial meningitis is an inflammation of the meninges which covers and protects the brain and the spinal cord. Such inflammation is mostly caused by blood-borne bacteria that cross the blood-brain barrier (BBB) and finally invade the brain parenchyma. Pathogens such as Streptococcus pneumoniae, Neisseria meningitidis, and Haemophilus influenzae are the main etiological causes of bacterial meningitis. After trafficking across the BBB, bacterial pathogens in the brain interact with neurons, the fundamental units of Central Nervous System, and other types of glial cells. Although the specific molecular mechanism behind the interaction between such pathogens with neurons is still under investigation, it is clear that bacterial interaction with neurons and neuroinflammatory responses within the brain leads to neuronal cell death. Furthermore, clinical studies have shown indications of meningitis-caused dementia; and a variety of neurodegenerative diseases such as Alzheimer's disease, Parkinson's disease and Huntington's disease are characterized by the loss of neurons, which, unlike many other eukaryotic cells, once dead or damaged, they are seldom replaced. The aim of this review article is to provide an overview of the knowledge on how bacterial pathogens in the brain damage neurons through direct and indirect interactions, and how the neuronal damage caused by bacterial pathogen can, in the long-term, influence the onset of neurodegenerative disorders.
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Affiliation(s)
| | | | - Federico Iovino
- Department of Neuroscience, Karolinska Institutet Biomedicum, Stockholm, Sweden
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15
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Jiménez-Munguía I, Tomečková Z, Mochnáčová E, Bhide K, Majerová P, Bhide M. Transcriptomic analysis of human brain microvascular endothelial cells exposed to laminin binding protein (adhesion lipoprotein) and Streptococcus pneumoniae. Sci Rep 2021; 11:7970. [PMID: 33846455 PMCID: PMC8041795 DOI: 10.1038/s41598-021-87021-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2020] [Accepted: 03/23/2021] [Indexed: 01/28/2023] Open
Abstract
Streptococcus pneumoniae invades the CNS and triggers a strong cellular response. To date, signaling events that occur in the human brain microvascular endothelial cells (hBMECs), in response to pneumococci or its surface adhesins are not mapped comprehensively. We evaluated the response of hBMECs to the adhesion lipoprotein (a laminin binding protein—Lbp) or live pneumococci. Lbp is a surface adhesin recently identified as a potential ligand, which binds to the hBMECs. Transcriptomic analysis was performed by RNA-seq of three independent biological replicates and validated with qRT-PCR using 11 genes. In total 350 differentially expressed genes (DEGs) were identified after infection with S. pneumoniae, whereas 443 DEGs when challenged with Lbp. Total 231 DEGs were common in both treatments. Integrative functional analysis revealed participation of DEGs in cytokine, chemokine, TNF signaling pathways and phagosome formation. Moreover, Lbp induced cell senescence and breakdown, and remodeling of ECM. This is the first report which maps complete picture of cell signaling events in the hBMECs triggered against S. pneumoniae and Lbp. The data obtained here could contribute in a better understanding of the invasion of pneumococci across BBB and underscores role of Lbp adhesin in evoking the gene expression in neurovascular unit.
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Affiliation(s)
- Irene Jiménez-Munguía
- Laboratory of Biomedical Microbiology and Immunology, University of Veterinary Medicine and Pharmacy in Kosice, Komenskeho 73, Kosice, 04181, Slovak Republic
| | - Zuzana Tomečková
- Laboratory of Biomedical Microbiology and Immunology, University of Veterinary Medicine and Pharmacy in Kosice, Komenskeho 73, Kosice, 04181, Slovak Republic
| | - Evelína Mochnáčová
- Laboratory of Biomedical Microbiology and Immunology, University of Veterinary Medicine and Pharmacy in Kosice, Komenskeho 73, Kosice, 04181, Slovak Republic
| | - Katarína Bhide
- Laboratory of Biomedical Microbiology and Immunology, University of Veterinary Medicine and Pharmacy in Kosice, Komenskeho 73, Kosice, 04181, Slovak Republic
| | - Petra Majerová
- Institute of Neuroimmunology of Slovak Academy of Sciences, Bratislava, Slovak Republic
| | - Mangesh Bhide
- Laboratory of Biomedical Microbiology and Immunology, University of Veterinary Medicine and Pharmacy in Kosice, Komenskeho 73, Kosice, 04181, Slovak Republic. .,Institute of Neuroimmunology of Slovak Academy of Sciences, Bratislava, Slovak Republic.
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16
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Selvaraj C, Vierra M, Dinesh DC, Abhirami R, Singh SK. Structural insights of macromolecules involved in bacteria-induced apoptosis in the pathogenesis of human diseases. ADVANCES IN PROTEIN CHEMISTRY AND STRUCTURAL BIOLOGY 2021; 126:1-38. [PMID: 34090612 DOI: 10.1016/bs.apcsb.2021.02.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Numbers of pathogenic bacteria can induce apoptosis in human host cells and modulate the cellular pathways responsible for inducing or inhibiting apoptosis. These pathogens are significantly recognized by host proteins and provoke the multitude of several signaling pathways and alter the cellular apoptotic stimuli. This process leads the bacterial entry into the mammalian cells and evokes a variety of responses like phagocytosis, release of mitochondrial cytochrome c, secretion of bacterial effectors, release of both apoptotic and inflammatory cytokines, and the triggering of apoptosis. Several mechanisms are involved in bacteria-induced apoptosis including, initiation of the endogenous death machinery, pore-forming proteins, and secretion of superantigens. Either small molecules or proteins may act as a binding partner responsible for forming the protein complexes and regulate enzymatic activity via protein-protein interactions. The bacteria induce apoptosis, attack the human cell and gain control over various types of cells and tissue. Since these processes are intricate in the defense mechanisms of host organisms against pathogenic bacteria and play an important function in host-pathogen interactions. In this chapter, we focus on the various bacterial-induced apoptosis mechanisms in host cells and discuss the important proteins and bacterial effectors that trigger the host cell apoptosis. The structural characterization of bacterial effector proteins and their interaction with human host cells are also considered.
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Affiliation(s)
- Chandrabose Selvaraj
- Computer Aided Drug Design and Molecular Modeling Lab, Department of Bioinformatics, Science Block, Alagappa University, Karaikudi, Tamil Nadu, India.
| | - Marisol Vierra
- Department of Pharmacology & Toxicology, Michigan State University, East Lansing, MI, United States
| | | | - Rajaram Abhirami
- Computer Aided Drug Design and Molecular Modeling Lab, Department of Bioinformatics, Science Block, Alagappa University, Karaikudi, Tamil Nadu, India
| | - Sanjeev Kumar Singh
- Computer Aided Drug Design and Molecular Modeling Lab, Department of Bioinformatics, Science Block, Alagappa University, Karaikudi, Tamil Nadu, India.
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17
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Wypij M, Jędrzejewski T, Ostrowski M, Trzcińska J, Rai M, Golińska P. Biogenic Silver Nanoparticles: Assessment of Their Cytotoxicity, Genotoxicity and Study of Capping Proteins. Molecules 2020; 25:E3022. [PMID: 32630696 PMCID: PMC7412363 DOI: 10.3390/molecules25133022] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Revised: 06/30/2020] [Accepted: 07/01/2020] [Indexed: 02/02/2023] Open
Abstract
The development of nanotechnology in the last two decades has led to the use of silver nanoparticles (AgNPs) in various biomedical applications, including antimicrobial, anti-inflammatory, and anticancer therapies. However, the potential of the medical application of AgNPs depends on the safety of their use. In this work, we assessed the in vitro cytotoxicity and genotoxicity of silver nanoparticles and identified biomolecules covering AgNPs synthesized from actinobacterial strain SH11. The cytotoxicity of AgNPs against MCF-7 human breast cancer cell line and murine macrophage cell line RAW 264.7 was studied by MTT assay, cell LDH (lactate dehydrogenase) release, and the measurement of ROS (reactive oxygen species) level while genotoxicity in Salmonella typhimurium cells was testing using the Ames test. The in vitro analysis showed that the tested nanoparticles demonstrated dose-dependent cytotoxicity against RAW 264.6 macrophages and MCF-7 breast cancer cells. Moreover, biosynthesized AgNPs did not show a mutagenic effect of S. typhimurium. The analyses and identification of biomolecules present on the surface of silver nanoparticles showed that they were associated with proteins. The SDS-PAGE (sodium dodecyl sulfate-polyacrylamide gel electrophoresis) analysis revealed the presence of 34 and 43 kDa protein bands. The identification of proteins performed by using LC-MS/MS (liquid chromatography with tandem mass spectrometry) demonstrated their highest homology to bacterial porins. Capping biomolecules of natural origin may be involved in the synthesis process of AgNPs or may be responsible for their stabilization. Moreover, the presence of natural proteins on the surface of bionanoparticles eliminates the postproduction steps of capping which is necessary for chemical synthesis to obtain the stable nanostructures required for application in medicine.
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Affiliation(s)
- Magdalena Wypij
- Department of Microbiology, Nicolaus Copernicus University, Lwowska 1, 87100 Torun, Poland;
| | - Tomasz Jędrzejewski
- Department of Immunology, Nicolaus Copernicus University, Lwowska 1, 87100 Torun, Poland;
| | - Maciej Ostrowski
- Department of Biochemistry, Nicolaus Copernicus University, Lwowska 1, 87100 Torun, Poland;
| | - Joanna Trzcińska
- Department of Microbiology, Nicolaus Copernicus University, Lwowska 1, 87100 Torun, Poland;
| | - Mahendra Rai
- Nanobiotechnology Lab., Department of Biotechnology, SGB Amravati University, Amravati, Maharashtra 444602, India;
| | - Patrycja Golińska
- Department of Microbiology, Nicolaus Copernicus University, Lwowska 1, 87100 Torun, Poland;
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18
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Káňová E, Tkáčová Z, Bhide K, Kulkarni A, Jiménez-Munguía I, Mertinková P, Drážovská M, Tyagi P, Bhide M. Transcriptome analysis of human brain microvascular endothelial cells response to Neisseria meningitidis and its antigen MafA using RNA-seq. Sci Rep 2019; 9:18763. [PMID: 31822804 PMCID: PMC6904618 DOI: 10.1038/s41598-019-55409-y] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2019] [Accepted: 11/28/2019] [Indexed: 01/25/2023] Open
Abstract
Interaction of Neisseria meningitidis (NM) with human brain microvascular endothelial cells (hBMECs) initiates of multiple cellular processes, which allow bacterial translocation across the blood-brain barrier (BBB). NM is equipped with several antigens, which interacts with the host cell receptors. Recently we have shown that adhesin MafA (UniProtKB-X5EG71), relatively less studied protein, is one of those surface exposed antigens that adhere to hBMECs. The present study was designed to comprehensively map the undergoing biological processes in hBMECs challenged with NM or MafA using RNA sequencing. 708 and 726 differentially expressed genes (DEGs) were identified in hBMECs exposed to NM and MafA, respectively. Gene ontology analysis of the DEGs revealed that several biological processes, which may alter the permeability of BBB, were activated. Comparative analysis of DEGs revealed that MafA, alike NM, might provoke TLR-dependent pathway and augment cytokine response. Moreover, both MafA and NM were able to induce genes involved in cell surface modifications, endocytosis, extracellular matrix remodulation and anoikis/apoptosis. In conclusion, this study for the first time describes effect of NM on the global gene expression in hBMECs using high-throughput RNA-seq. It also presents ability of MafA to induce gene expression, which might aid NM in breaching the BBB.
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Affiliation(s)
- Evelína Káňová
- Laboratory of Biomedical Microbiology and Immunology, The University of Veterinary Medicine and Pharmacy, Komenskeho 73, 04001, Kosice, Slovakia
| | - Zuzana Tkáčová
- Laboratory of Biomedical Microbiology and Immunology, The University of Veterinary Medicine and Pharmacy, Komenskeho 73, 04001, Kosice, Slovakia
| | - Katarína Bhide
- Laboratory of Biomedical Microbiology and Immunology, The University of Veterinary Medicine and Pharmacy, Komenskeho 73, 04001, Kosice, Slovakia
| | - Amod Kulkarni
- Laboratory of Biomedical Microbiology and Immunology, The University of Veterinary Medicine and Pharmacy, Komenskeho 73, 04001, Kosice, Slovakia
| | - Irene Jiménez-Munguía
- Laboratory of Biomedical Microbiology and Immunology, The University of Veterinary Medicine and Pharmacy, Komenskeho 73, 04001, Kosice, Slovakia
| | - Patrícia Mertinková
- Laboratory of Biomedical Microbiology and Immunology, The University of Veterinary Medicine and Pharmacy, Komenskeho 73, 04001, Kosice, Slovakia
| | - Monika Drážovská
- Laboratory of Biomedical Microbiology and Immunology, The University of Veterinary Medicine and Pharmacy, Komenskeho 73, 04001, Kosice, Slovakia
| | - Punit Tyagi
- Laboratory of Biomedical Microbiology and Immunology, The University of Veterinary Medicine and Pharmacy, Komenskeho 73, 04001, Kosice, Slovakia
| | - Mangesh Bhide
- Laboratory of Biomedical Microbiology and Immunology, The University of Veterinary Medicine and Pharmacy, Komenskeho 73, 04001, Kosice, Slovakia. .,Institute of Neuroimmunology of Slovak Academy of Sciences, 84510, Bratislava, Slovakia.
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19
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Neisseria meningitidis Type IV Pili Trigger Ca 2+-Dependent Lysosomal Trafficking of the Acid Sphingomyelinase To Enhance Surface Ceramide Levels. Infect Immun 2019; 87:IAI.00410-19. [PMID: 31160362 DOI: 10.1128/iai.00410-19] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Accepted: 05/24/2019] [Indexed: 01/26/2023] Open
Abstract
Acid sphingomyelinase (ASM) is a lipid hydrolase that converts sphingomyelin to ceramide and that can be activated by various cellular stress mechanisms, including bacterial pathogens. Vesicle transportation or trafficking of ASM from the lysosomal compartment to the cell membrane is a prerequisite for its activation in response to bacterial infections; however, the effectors and mechanisms of ASM translocation and activation are poorly defined. Our recent work documented the key importance of ASM for Neisseria meningitidis uptake into human brain microvascular endothelial cells (HBMEC). We clearly identified OpcA to be one bacterial effector promoting ASM translocation and activity, though it became clear that additional bacterial components were involved, as up to 80% of ASM activity and ceramide generation was retained in cells infected with an opcA-deficient mutant. We hypothesized that N. meningitidis might use pilus components to promote the translocation of ASM into HBMEC. Indeed, we found that both live, piliated N. meningitidis and pilus-enriched fractions trigger transient ASM surface display, followed by the formation of ceramide-rich platforms (CRPs). By using indirect immunocytochemistry and direct stochastic optical reconstruction microscopy, we show that the overall number of CRPs with a size of ∼80 nm in the plasma membrane is significantly increased after exposure to pilus-enriched fractions. Infection with live bacteria as well as exposure to pilus-enriched fractions transiently increased cytosolic Ca2+ levels in HBMEC, and this was found to be important for ASM surface display mediated by lysosomal exocytosis, as depletion of cytosolic Ca2+ resulted in a significant decrease in ASM surface levels, ASM activity, and CRP formation.
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20
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Abstract
Outer-membrane porins are often considered as passive conduits of small molecules across lipid bilayers. Using native mass spectrometry experiments we identify a pH-sensitive lipid-binding mechanism of outer membrane porin F, which enables increased threading of a colicin-derived peptide through open channels. Supported by molecular dynamics simulations and channel recording experiments, we posit that this mechanism attenuates channel opening in response to changes in environmental conditions, specifically pH. These findings have important consequences for mass spectrometry experiments, wherein the role of charge is often overlooked, and they also could help provide understanding of antibiotics that gain access to Gram-negative bacteria through porin-mediated pathways. Strong interactions between lipids and proteins occur primarily through association of charged headgroups and amino acid side chains, rendering the protonation status of both partners important. Here we use native mass spectrometry to explore lipid binding as a function of charge of the outer membrane porin F (OmpF). We find that binding of anionic phosphatidylglycerol (POPG) or zwitterionic phosphatidylcholine (POPC) to OmpF is sensitive to electrospray polarity while the effects of charge are less pronounced for other proteins in outer or mitochondrial membranes: the ferripyoverdine receptor (FpvA) or the voltage-dependent anion channel (VDAC). Only marginal charge-induced differences were observed for inner membrane proteins: the ammonia channel (AmtB) or the mechanosensitive channel. To understand these different sensitivities, we performed an extensive bioinformatics analysis of membrane protein structures and found that OmpF, and to a lesser extent FpvA and VDAC, have atypically high local densities of basic and acidic residues in their lipid headgroup-binding regions. Coarse-grained molecular dynamics simulations, in mixed lipid bilayers, further implicate changes in charge by demonstrating preferential binding of anionic POPG over zwitterionic POPC to protonated OmpF, an effect not observed to the same extent for AmtB. Moreover, electrophysiology and mass-spectrometry–based ligand-binding experiments, at low pH, show that POPG can maintain OmpF channels in open conformations for extended time periods. Since the outer membrane is composed almost entirely of anionic lipopolysaccharide, with similar headgroup properties to POPG, such anionic lipid binding could prevent closure of OmpF channels, thereby increasing access of antibiotics that use porin-mediated pathways.
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21
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Zhu W, Tomberg J, Knilans KJ, Anderson JE, McKinnon KP, Sempowski GD, Nicholas RA, Duncan JA. Properly folded and functional PorB from Neisseria gonorrhoeae inhibits dendritic cell stimulation of CD4 + T cell proliferation. J Biol Chem 2018; 293:11218-11229. [PMID: 29752412 DOI: 10.1074/jbc.ra117.001209] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2017] [Revised: 04/19/2018] [Indexed: 12/14/2022] Open
Abstract
Neisseria gonorrhoeae is an exclusive human pathogen that evades the host immune system through multiple mechanisms. We have shown that N. gonorrhoeae suppresses the capacity of antigen-presenting cells to induce CD4+ T cell proliferation. In this study, we sought to determine the gonococcal factors involved in this adaptive immune suppression. We show that suppression of the capacity of antigen-pulsed dendritic cells to induce T cell proliferation is recapitulated by administration of a high-molecular-weight fraction of conditioned medium from N. gonorrhoeae cultures, which includes outer membrane vesicles that are shed during growth of the bacteria. N. gonorrhoeae PorB is the most abundant protein in N. gonorrhoeae-derived vesicles, and treatment of dendritic cells with purified recombinant PorB inhibited the capacity of the cells to stimulate T cell proliferation. This immunosuppressive feature of purified PorB depended on proper folding of the protein. PorB from N. gonorrhoeae, as well as other Neisseria species and other Gram-negative bacterial species, are known to activate host Toll-like receptor 2 (TLR2) signaling. Published studies have demonstrated that purified Neisseria PorB forms proteinacious nanoparticles, termed proteosomes, when detergent micelles are removed. Unlike folded, detergent-solubilized PorB, PorB proteosomes stimulate immune responses. We now demonstrate that the formation of PorB proteosomes from structurally intact PorB eliminates the immunosuppressive property of the protein while enhancing TLR2 stimulation. These findings suggest that gonococcal PorB present in shed outer membrane vesicles plays a role in suppression of adaptive immune responses to this immune-evasive pathogen.
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Affiliation(s)
- Weiyan Zhu
- From the Department of Medicine, Division of Infectious Diseases, University of North Carolina, Chapel Hill, North Carolina 27599
| | - Joshua Tomberg
- the Department of Pharmacology, University of North Carolina, Chapel Hill, North Carolina 27599
| | - Kayla J Knilans
- the Department of Pharmacology, University of North Carolina, Chapel Hill, North Carolina 27599
| | - James E Anderson
- From the Department of Medicine, Division of Infectious Diseases, University of North Carolina, Chapel Hill, North Carolina 27599
| | - Karen P McKinnon
- the Department of Microbiology and Immunology, University of North Carolina, Chapel Hill, North Carolina 27599, and.,the Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, North Carolina 27599
| | - Gregory D Sempowski
- the Department of Medicine and Human Vaccine Institute, Duke University Medical Center, Durham, North Carolina 27710
| | - Robert A Nicholas
- the Department of Pharmacology, University of North Carolina, Chapel Hill, North Carolina 27599, .,the Department of Microbiology and Immunology, University of North Carolina, Chapel Hill, North Carolina 27599, and
| | - Joseph A Duncan
- From the Department of Medicine, Division of Infectious Diseases, University of North Carolina, Chapel Hill, North Carolina 27599, .,the Department of Pharmacology, University of North Carolina, Chapel Hill, North Carolina 27599.,the Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, North Carolina 27599
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22
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Kumar V, Ahmad A. Targeting calpains: A novel immunomodulatory approach for microbial infections. Eur J Pharmacol 2017; 814:28-44. [PMID: 28789934 DOI: 10.1016/j.ejphar.2017.08.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2017] [Revised: 08/01/2017] [Accepted: 08/03/2017] [Indexed: 02/09/2023]
Abstract
Calpains are a family of Ca2+ dependent cytosolic non-lysosomal proteases with well conserved cysteine-rich domains for enzymatic activity. Due to their functional dependency on Ca2+ concentrations, they are involved in various cellular processes that are regulated by intracellular ca2+ concentration (i.e. embryo development, cell development and migration, maintenance of cellular architecture and structure etc.). Calpains are widely studied proteases in mammalian (i.e. mouse and human) physiology and pathophysiology due to their ubiquitous presence. For example, these proteases have been found to be involved in various inflammatory disorders such as neurodegeneration, cancer, brain and myocardial ischemia and infarction, cataract and muscular dystrophies etc. Besides their role in these sterile inflammatory conditions, calpains have also been shown to regulate a wide range of infectious diseases (i.e. sepsis, tuberculosis, gonorrhoea and bacillary dysentery etc.). One of these regulatory mechanisms mediated by calpains (i.e. calpain 1 and 2) during microbial infections involves the regulation of innate immune response, inflammation and cell death. Thus, the major emphasis of this review is to highlight the importance of calpains in the pathogenesis of various microbial (i.e. bacterial, fungal and viral) diseases and the use of calpain modulators as potential immunomodulators in microbial infections.
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Affiliation(s)
- Vijay Kumar
- Department of Paediatrics and Child Health, Children's Health Queensland Clinical Unit, School of Medicine, University of Queensland, Brisbane, Queensland, Australia.
| | - Ali Ahmad
- Laboratory of innate immunity, CHU Ste-Justine Research Center/Department of Microbiology, Infectious Diseases and Immunology, University of Montreal, 3175 Cote Ste Catherine, Montreal, Quebec, Canada H3T 1C5.
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Di DD, Jiang H, Tian LL, Kang JL, Zhang W, Yi XP, Ye F, Zhong Q, Ni B, He YY, Xia L, Yu Y, Cui BY, Mao X, Fan WX. Comparative genomic analysis between newly sequenced Brucella suis Vaccine Strain S2 and the Virulent Brucella suis Strain 1330. BMC Genomics 2016; 17:741. [PMID: 27645563 PMCID: PMC5029015 DOI: 10.1186/s12864-016-3076-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2015] [Accepted: 09/07/2016] [Indexed: 11/16/2022] Open
Abstract
Background Brucellosis is a bacterial disease caused by Brucella infection. In the late fifties, Brucella suis vaccine strain S2 with reduced virulence was obtained by serial transfer of a virulent B. suis biovar 1 strain in China. It has been widely used for vaccination in China since 1971. Until now, the mechanisms underlie virulence attenuation of S2 are still unknown. Results In this paper, the whole genome sequencing of S2 was carried out by Illumina Hiseq2000 sequencing method. We further performed the comparative genomic analysis to find out the differences between S2 and the virulent Brucella suis strain 1330. We found premature stops in outer membrane autotransporter omaA and eryD genes. Single mutations were found in phosphatidylcholine synthase, phosphorglucosamine mutase, pyruvate kinase and FliF, which have been reported to be related to the virulence of Brucella or other bacteria. Of the other different proteins between S2 and 1330, such as Omp2b, periplasmic sugar-binding protein, and oligopeptide ABC transporter, no definitive implications related to bacterial virulence were found, which await further investigation. Conclusions The data presented here provided the rational basis for designing Brucella vaccines that could be used in other strains. Electronic supplementary material The online version of this article (doi:10.1186/s12864-016-3076-5) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Dong-Dong Di
- Laboratory of Zoonoses, China Animal Health and Epidemiology Center, Qingdao, Shandong, China
| | - Hai Jiang
- State Key Laboratory for Infectious Disease Prevention and Control, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, National Institute for Communicable Disease Control and Prevention, Beijing, China
| | - Li-Li Tian
- Laboratory of Zoonoses, China Animal Health and Epidemiology Center, Qingdao, Shandong, China
| | - Jing-Li Kang
- Laboratory of Zoonoses, China Animal Health and Epidemiology Center, Qingdao, Shandong, China
| | - Wen Zhang
- State Key Laboratory for Infectious Disease Prevention and Control, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, National Institute for Communicable Disease Control and Prevention, Beijing, China
| | - Xin-Ping Yi
- Xinjiang Academy of Animal Science, Institute of Veterinary Research, Urumuqi, Xinjiang, China
| | - Feng Ye
- Xinjiang Academy of Animal Science, Institute of Veterinary Research, Urumuqi, Xinjiang, China
| | - Qi Zhong
- Xinjiang Academy of Animal Science, Institute of Veterinary Research, Urumuqi, Xinjiang, China
| | - Bo Ni
- Laboratory of Zoonoses, China Animal Health and Epidemiology Center, Qingdao, Shandong, China
| | - You-Yu He
- ZhongXin Biotechology Shanghai Co, Ltd. 12F, Building 1, 100 Qinzhou Road, Shanghai, China
| | - Lin Xia
- ZhongXin Biotechology Shanghai Co, Ltd. 12F, Building 1, 100 Qinzhou Road, Shanghai, China
| | - Yao Yu
- ZhongXin Biotechology Shanghai Co, Ltd. 12F, Building 1, 100 Qinzhou Road, Shanghai, China
| | - Bu-Yun Cui
- State Key Laboratory for Infectious Disease Prevention and Control, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, National Institute for Communicable Disease Control and Prevention, Beijing, China.
| | - Xiang Mao
- Chinese Academy of Agricultural Sciences, Shanghai Veterinary Research Institute, Shanghai, China.
| | - Wei-Xing Fan
- Laboratory of Zoonoses, China Animal Health and Epidemiology Center, Qingdao, Shandong, China.
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24
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Hill SA, Masters TL, Wachter J. Gonorrhea - an evolving disease of the new millennium. MICROBIAL CELL (GRAZ, AUSTRIA) 2016; 3:371-389. [PMID: 28357376 PMCID: PMC5354566 DOI: 10.15698/mic2016.09.524] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/09/2015] [Accepted: 01/30/2016] [Indexed: 12/21/2022]
Abstract
Etiology, transmission and protection: Neisseria gonorrhoeae (the gonococcus) is the etiological agent for the strictly human sexually transmitted disease gonorrhea. Infections lead to limited immunity, therefore individuals can become repeatedly infected. Pathology/symptomatology: Gonorrhea is generally a non-complicated mucosal infection with a pustular discharge. More severe sequellae include salpingitis and pelvic inflammatory disease which may lead to sterility and/or ectopic pregnancy. Occasionally, the organism can disseminate as a bloodstream infection. Epidemiology, incidence and prevalence: Gonorrhea is a global disease infecting approximately 60 million people annually. In the United States there are approximately 300, 000 cases each year, with an incidence of approximately 100 cases per 100,000 population. Treatment and curability: Gonorrhea is susceptible to an array of antibiotics. Antibiotic resistance is becoming a major problem and there are fears that the gonococcus will become the next "superbug" as the antibiotic arsenal diminishes. Currently, third generation extended-spectrum cephalosporins are being prescribed. Molecular mechanisms of infection: Gonococci elaborate numerous strategies to thwart the immune system. The organism engages in extensive phase (on/off switching) and antigenic variation of several surface antigens. The organism expresses IgA protease which cleaves mucosal antibody. The organism can become serum resistant due to its ability to sialylate lipooligosaccharide in conjunction with its ability to subvert complement activation. The gonococcus can survive within neutrophils as well as in several other lymphocytic cells. The organism manipulates the immune response such that no immune memory is generated which leads to a lack of protective immunity.
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Affiliation(s)
- Stuart A. Hill
- Department of Epidemiology, Gillings School of Global Public Health,
University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-7435
| | - Thao L. Masters
- Department of Epidemiology, Gillings School of Global Public Health,
University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-7435
| | - Jenny Wachter
- Department of Epidemiology, Gillings School of Global Public Health,
University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-7435
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25
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Peak IR, Chen A, Jen FEC, Jennings C, Schulz BL, Saunders NJ, Khan A, Seifert HS, Jennings MP. Neisseria meningitidis Lacking the Major Porins PorA and PorB Is Viable and Modulates Apoptosis and the Oxidative Burst of Neutrophils. J Proteome Res 2016; 15:2356-65. [PMID: 26562068 DOI: 10.1021/acs.jproteome.5b00938] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The bacterial pathogen Neisseria meningitidis expresses two major outer-membrane porins. PorA expression is subject to phase-variation (high frequency, random, on-off switching), and both PorA and PorB are antigenically variable between strains. PorA expression is variable and not correlated with meningococcal colonisation or invasive disease, whereas all naturally-occurring strains express PorB suggesting strong selection for expression. We have generated N. meningitidis strains lacking expression of both major porins, demonstrating that they are dispensable for bacterial growth in vitro. The porAB mutant strain has an exponential growth rate similar to the parental strain, as do the single porA or porB mutants, but the porAB mutant strain does not reach the same cell density in stationary phase. Proteomic analysis suggests that the double mutant strain exhibits compensatory expression changes in proteins associated with cellular redox state, energy/nutrient metabolism, and membrane stability. On solid media, there is obvious growth impairment that is rescued by addition of blood or serum from mammalian species, particularly heme. These porin mutants are not impaired in their capacity to inhibit both staurosporine-induced apoptosis and a phorbol 12-myristate 13-acetate-induced oxidative burst in human neutrophils suggesting that the porins are not the only bacterial factors that can modulate these processes in host cells.
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Affiliation(s)
- Ian R Peak
- School of Medical Science, Gold Coast Campus, Griffith University , Southport, QLD 4222, Australia.,Institute for Glycomics, Gold Coast Campus, Griffith University , Southport, QLD 4222, Australia
| | - Adrienne Chen
- Department of Microbiology-Immunology, Feinberg School of Medicine, Northwestern University , 303 East Chicago Avenue, Chicago, Illinois 60611, United States
| | - Freda E-C Jen
- Institute for Glycomics, Gold Coast Campus, Griffith University , Southport, QLD 4222, Australia
| | - Courtney Jennings
- Institute for Glycomics, Gold Coast Campus, Griffith University , Southport, QLD 4222, Australia
| | - Benjamin L Schulz
- Australian Infectious Diseases Research Centre, School of Chemistry and Molecular Biosciences, The University of Queensland , St. Lucia, Brisbane, QLD 4072, Australia
| | - Nigel J Saunders
- Centre for Systems and Synthetic Biology, Brunel University , Uxbridge, Middlesex UB8 3PH, U.K
| | - Arshad Khan
- Centre for Systems and Synthetic Biology, Brunel University , Uxbridge, Middlesex UB8 3PH, U.K
| | - H Steven Seifert
- Department of Microbiology-Immunology, Feinberg School of Medicine, Northwestern University , 303 East Chicago Avenue, Chicago, Illinois 60611, United States
| | - Michael P Jennings
- Institute for Glycomics, Gold Coast Campus, Griffith University , Southport, QLD 4222, Australia
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26
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Château A, Seifert HS. Neisseria gonorrhoeae survives within and modulates apoptosis and inflammatory cytokine production of human macrophages. Cell Microbiol 2016; 18:546-60. [PMID: 26426083 PMCID: PMC5240846 DOI: 10.1111/cmi.12529] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2015] [Revised: 09/17/2015] [Accepted: 09/28/2015] [Indexed: 12/28/2022]
Abstract
The human-adapted organism Neisseria gonorrhoeae is the causative agent of gonorrhoea, a sexually transmitted infection. It readily colonizes the genital, rectal and nasalpharyngeal mucosa during infection. While it is well established that N. gonorrhoeae recruits and modulates the functions of polymorphonuclear leukocytes during infection, how N. gonorrhoeae interacts with macrophages present in infected tissue is not fully defined. We studied the interactions of N. gonorrhoeae with two human monocytic cell lines, THP-1 and U937, and primary monocytes, all differentiated into macrophages. Most engulfed bacteria were killed in the phagolysosome, but a subset of bacteria was able to survive and replicate inside the macrophages suggesting that those cells may be an unexplored cellular reservoir for N. gonorrhoeae during infection. N. gonorrhoeae was able to modulate macrophage apoptosis: N. gonorrhoeae induced apoptosis in THP-1 cells whereas it inhibited induced apoptosis in U937 cells and primary human macrophages. Furthermore, N. gonorrhoeae induced expression of inflammatory cytokines in macrophages, suggesting a role for macrophages in recruiting polymorphonuclear leukocytes to the site of infection. These results indicate macrophages may serve as a significant replicative niche for N. gonorrhoeae and play an important role in gonorrheal pathogenesis.
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Affiliation(s)
- Alice Château
- Department of Microbiology-Immunology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611
| | - H. Steven Seifert
- Department of Microbiology-Immunology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611
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27
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Bisle S, Klingenbeck L, Borges V, Sobotta K, Schulze-Luehrmann J, Menge C, Heydel C, Gomes JP, Lührmann A. The inhibition of the apoptosis pathway by the Coxiella burnetii effector protein CaeA requires the EK repetition motif, but is independent of survivin. Virulence 2016; 7:400-12. [PMID: 26760129 DOI: 10.1080/21505594.2016.1139280] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
Abstract
ABSRTACT Coxiella burnetii is an obligate intracellular bacterium that causes Query (Q) fever, a zoonotic disease. It requires a functional type IV secretion system (T4SS) which translocate bacterial effector proteins into the host cell cytoplasm and thereby facilitates bacterial replication. To date, more than 130 effector proteins have been identified, but their functions remain largely unknown. Recently, we demonstrated that one of these proteins, CaeA (CBU1524) localized to the host cell nucleus and inhibited intrinsic apoptosis of HEK293 or CHO cells. In the present study we addressed the question whether CaeA also affects the extrinsic apoptosis pathway. Ectopic expression of CaeA reduced extrinsic apoptosis and prevented the cleavage of the executioner caspase 7, but did not impair the activation of initiator caspase 9. CaeA expression resulted in an up-regulation of survivin (an inhibitor of activated caspases), which, however, was not causal for the anti-apoptotic effect of CaeA. Comparing the sequence of CaeA from 25 different C. burnetii isolates we identified an EK (glutamic acid/ lysine) repetition motif as a site of high genetic variability. The EK motif of CaeA was essential for the anti-apoptotic activity of CaeA. From these data, we conclude that the C. burnetii effector protein CaeA interferes with the intrinsic and extrinsic apoptosis pathway. The process requires the EK repetition motif of CaeA, but is independent of the upregulated expression of survivin.
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Affiliation(s)
- Stephanie Bisle
- a Mikrobiologisches Institut - Klinische Mikrobiologie, Immunologie und Hygiene, Universitätsklinikum Erlangen, Friedrich-Alexander Universität (FAU) Erlangen-Nürnberg , Erlangen , Germany
| | - Leonie Klingenbeck
- a Mikrobiologisches Institut - Klinische Mikrobiologie, Immunologie und Hygiene, Universitätsklinikum Erlangen, Friedrich-Alexander Universität (FAU) Erlangen-Nürnberg , Erlangen , Germany
| | - Vítor Borges
- b Bioinformatics Unit, Department of Infectious Diseases, National Institute of Health , Lisbon , Portugal
| | - Katharina Sobotta
- c Friedrich-Loeffler-Institut, Institute of Molecular Pathogenesis , Jena , Germany
| | - Jan Schulze-Luehrmann
- a Mikrobiologisches Institut - Klinische Mikrobiologie, Immunologie und Hygiene, Universitätsklinikum Erlangen, Friedrich-Alexander Universität (FAU) Erlangen-Nürnberg , Erlangen , Germany
| | - Christian Menge
- c Friedrich-Loeffler-Institut, Institute of Molecular Pathogenesis , Jena , Germany
| | - Carsten Heydel
- d Institut für Hygiene und Infektionskrankheiten der Tiere, Justus Liebig Universität Gießen , Gießen , Germany
| | - João Paulo Gomes
- b Bioinformatics Unit, Department of Infectious Diseases, National Institute of Health , Lisbon , Portugal
| | - Anja Lührmann
- a Mikrobiologisches Institut - Klinische Mikrobiologie, Immunologie und Hygiene, Universitätsklinikum Erlangen, Friedrich-Alexander Universität (FAU) Erlangen-Nürnberg , Erlangen , Germany
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Gupta S, Prasad GVRK, Mukhopadhaya A. Vibrio cholerae Porin OmpU Induces Caspase-independent Programmed Cell Death upon Translocation to the Host Cell Mitochondria. J Biol Chem 2015; 290:31051-68. [PMID: 26559970 DOI: 10.1074/jbc.m115.670182] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2015] [Indexed: 12/11/2022] Open
Abstract
Porins, a major class of outer membrane proteins in Gram-negative bacteria, primarily act as transport channels. OmpU is one of the major porins of human pathogen, Vibrio cholerae. In the present study, we show that V. cholerae OmpU has the ability to induce target cell death. Although OmpU-mediated cell death shows some characteristics of apoptosis, such as flipping of phosphatidylserine in the membrane as well as cell size shrinkage and increased cell granularity, it does not show the caspase-3 activation and DNA laddering pattern typical of apoptotic cells. Increased release of lactate dehydrogenase in OmpU-treated cells indicates that the OmpU-mediated cell death also has characteristics of necrosis. Further, we show that the mechanism of OmpU-mediated cell death involves major mitochondrial changes in the target cells. We observe that OmpU treatment leads to the disruption of mitochondrial membrane potential, resulting in the release of cytochrome c and apoptosis-inducing factor (AIF). AIF translocates to the host cell nucleus, implying that it has a crucial role in OmpU-mediated cell death. Finally, we observe that OmpU translocates to the target cell mitochondria, where it directly initiates mitochondrial changes leading to mitochondrial membrane permeability transition and AIF release. Partial blocking of AIF release by cyclosporine A in OmpU-treated cells further suggests that OmpU may be inducing the opening of the mitochondrial permeability transition pore. All of these results lead us to the conclusion that OmpU induces cell death in target cells in a programmed manner in which mitochondria play a central role.
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Affiliation(s)
- Shelly Gupta
- From the Department of Biological Sciences, Indian Institute of Science Education and Research Mohali, Knowledge City, Sector 81, SAS Nagar, Mohali 140306, Punjab, India
| | - G V R Krishna Prasad
- From the Department of Biological Sciences, Indian Institute of Science Education and Research Mohali, Knowledge City, Sector 81, SAS Nagar, Mohali 140306, Punjab, India
| | - Arunika Mukhopadhaya
- From the Department of Biological Sciences, Indian Institute of Science Education and Research Mohali, Knowledge City, Sector 81, SAS Nagar, Mohali 140306, Punjab, India
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Sakharwade SC, Mukhopadhaya A. Vibrio cholerae porin OmpU induces LPS tolerance by attenuating TLR-mediated signaling. Mol Immunol 2015; 68:312-24. [PMID: 26454478 DOI: 10.1016/j.molimm.2015.09.021] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2015] [Revised: 09/21/2015] [Accepted: 09/23/2015] [Indexed: 12/31/2022]
Abstract
Porins can act as pathogen-associated molecular patterns, can be recognized by the host immune system and modulate immune responses. Vibrio choleraeporin OmpU aids in bacterial survival in the human gut by increasing resistance against bile acids and anti-microbial peptides. V. choleraeOmpU is pro-inflammatory in nature. However, interestingly, it can also down-regulate LPS-mediated pro-inflammatory responses. In this study, we have explored how OmpU-pretreatment affects LPS-mediated responses. Our study indicates that OmpU-pretreatment followed by LPS-activation does not induce M2-polarization of macrophages/monocytes. Further, OmpU attenuates LPS-mediated TLR2/TLR6 signaling by decreasing the association of TLRs along with recruitment of MyD88 and IRAKs to the receptor complex. This results in decreased translocation of NFκB in the nucleus. Additionally, OmpU-pretreatment up-regulates expression of IRAK-M, a negative regulator of TLR signaling, in RAW 264.7 mouse macrophage cells upon LPS-stimulation. Suppressor cytokine IL-10 is partially involved in OmpU-induced down-regulation of LPS-mediated TNFα production in human PBMCs. Furthermore, OmpU-pretreatment also affects macrophage function, by enhancing phagocytosis in LPS-treated RAW 264.7 cells, and down-regulates LPS-induced cell surface expression of co-stimulatory molecules. Altogether, OmpU causes suppression of LPS-mediated responses by attenuating the LPS-mediated TLR signaling pathway.
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Affiliation(s)
- Sanica C Sakharwade
- Department of Biological Sciences, Indian Institute of Science Education and Research (IISER) Mohali, Sector 81, SAS Nagar, Manauli, 140306 Punjab, India
| | - Arunika Mukhopadhaya
- Department of Biological Sciences, Indian Institute of Science Education and Research (IISER) Mohali, Sector 81, SAS Nagar, Manauli, 140306 Punjab, India.
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30
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Besbes A, Le Goff S, Antunes A, Terrade A, Hong E, Giorgini D, Taha MK, Deghmane AE. Hyperinvasive Meningococci Induce Intra-nuclear Cleavage of the NF-κB Protein p65/RelA by Meningococcal IgA Protease. PLoS Pathog 2015; 11:e1005078. [PMID: 26241037 PMCID: PMC4524725 DOI: 10.1371/journal.ppat.1005078] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2014] [Accepted: 07/10/2015] [Indexed: 11/30/2022] Open
Abstract
Differential modulation of NF-κB during meningococcal infection is critical in innate immune response to meningococcal disease. Non-invasive isolates of Neisseria meningitidis provoke a sustained NF-κB activation in epithelial cells. However, the hyperinvasive isolates of the ST-11 clonal complex (ST-11) only induce an early NF-κB activation followed by a sustained activation of JNK and apoptosis. We show that this temporal activation of NF-κB was caused by specific cleavage at the C-terminal region of NF-κB p65/RelA component within the nucleus of infected cells. This cleavage was mediated by the secreted 150 kDa meningococcal ST-11 IgA protease carrying nuclear localisation signals (NLS) in its α-peptide moiety that allowed efficient intra-nuclear transport. In a collection of non-ST-11 healthy carriage isolates lacking NLS in the α-peptide, secreted IgA protease was devoid of intra-nuclear transport. This part of iga polymorphism allows non-invasive isolates lacking NLS, unlike hyperinvasive ST-11 isolates of N. meningitides habouring NLS in their α-peptide, to be carried asymptomatically in the human nasopharynx through selective eradication of their ability to induce apoptosis in infected epithelial cells.
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Affiliation(s)
- Anissa Besbes
- Institut Pasteur, Invasive Bacterial Infections Unit, Paris, France
| | - Salomé Le Goff
- Institut Pasteur, Invasive Bacterial Infections Unit, Paris, France
| | - Ana Antunes
- Institut Pasteur, Invasive Bacterial Infections Unit, Paris, France
| | - Aude Terrade
- Institut Pasteur, Invasive Bacterial Infections Unit, Paris, France
| | - Eva Hong
- Institut Pasteur, Invasive Bacterial Infections Unit, Paris, France
| | - Dario Giorgini
- Institut Pasteur, Invasive Bacterial Infections Unit, Paris, France
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31
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Neisseria gonorrhoeae Modulates Cell Death in Human Endocervical Epithelial Cells through Export of Exosome-Associated cIAP2. Infect Immun 2015; 83:3410-7. [PMID: 26077759 DOI: 10.1128/iai.00732-15] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2015] [Indexed: 01/07/2023] Open
Abstract
Several bacterial pathogens persist and survive in the host by modulating host cell death pathways. We previously demonstrated that Neisseria gonorrhoeae, a Gram-negative pathogen responsible for the sexually transmitted infection gonorrhea, protects against exogenous induction of apoptosis in human cervical epithelial cells. However, induction of cell death by N. gonorrhoeae has also been reported in other cell types. The mechanisms by which N. gonorrhoeae modulates cell death are not clear, although a role for the inhibitor of apoptosis-2 (cIAP2) has been proposed. In this study, we confirmed that N. gonorrhoeae induces production of cIAP2 in human cervical epithelial cells. High levels of intracellular cIAP2 were detected early after N. gonorrhoeae stimulation, which was followed by a marked decrease at 24 h. At this time point, we observed increased levels of extracellular cIAP2 associated with exosomes and an overall increase in production of exosomes. Inhibition of cIAP2 in N. gonorrhoeae-stimulated epithelial cells resulted in increased cell death and interleukin-1β (IL-1β) production. Collectively these results indicate that N. gonorrhoeae stimulation of human endocervical epithelial cells induces the release of cIAP2, an essential regulator of cell death and immune signaling.
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32
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Khan J, Sharma PK, Mukhopadhaya A. Vibrio cholerae porin OmpU mediates M1-polarization of macrophages/monocytes via TLR1/TLR2 activation. Immunobiology 2015; 220:1199-209. [PMID: 26093918 DOI: 10.1016/j.imbio.2015.06.009] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2015] [Revised: 05/04/2015] [Accepted: 06/01/2015] [Indexed: 01/01/2023]
Abstract
Polarization of the monocytes and macrophages toward the M1 and M2 states is important for hosts' defense against the pathogens. Moreover, it plays a crucial role to resolve the overwhelming inflammatory responses that can be harmful to the host. Polarization of macrophages/monocytes can be induced by pathogen-associated molecular patterns (PAMPs). PAMP-mediated monocyte/macrophage polarization is important during the infection, as pathogen can suppress host immune system by altering the polarization status of the macrophages/monocytes. OmpU, an outer membrane porin protein of Vibrio cholerae, possesses the ability to induce pro-inflammatory responses in monocytes/macrophages. It is also able to down-regulate the LPS-mediated activation of the monocytes/macrophages. Such observation leads us to believe that OmpU may induce a state that can be called as M1/M2-intermediate state. In the present study, we evaluated a set of M1 and M2 markers in RAW 264.7 murine macrophage cell line, and THP-1 human monocytic cell line, in response to the purified OmpU protein. We observed that OmpU, as a PAMP, induced M1-polarization by activating the Toll-like receptor (TLR) signaling pathway. OmpU induced formation of TLR1/TLR2-heterodimers. OmpU-mediated TLR-activation led to the MyD88 recruitment to the TLR1/TLR2 complex. MyD88, in turn, recruited IRAK1. Ultimately, OmpU-mediated signaling led to the activation and subsequent nuclear translocation of the NFκB p65 subunit. We also observed that blocking of the TLR1, TLR2, IRAK1, and NFκB affected OmpU-mediated production of M1-associated pro-inflammatory cytokines such as TNFα and IL-6.
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Affiliation(s)
- Junaid Khan
- Department of Biological Sciences, Indian Institute of Science Education and Research (IISER) Mohali, Knowledge City, Sector 81, SAS Nagar, Mohali, Punjab 140306, India
| | - Praveen K Sharma
- Department of Biological Sciences, Indian Institute of Science Education and Research (IISER) Mohali, Knowledge City, Sector 81, SAS Nagar, Mohali, Punjab 140306, India
| | - Arunika Mukhopadhaya
- Department of Biological Sciences, Indian Institute of Science Education and Research (IISER) Mohali, Knowledge City, Sector 81, SAS Nagar, Mohali, Punjab 140306, India.
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33
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Quintero CA, Tudela JG, Damiani MT. Rho GTPases as pathogen targets: Focus on curable sexually transmitted infections. Small GTPases 2015; 6:108-18. [PMID: 26023809 DOI: 10.4161/21541248.2014.991233] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Pathogens have evolved highly specialized mechanisms to infect hosts. Several microorganisms modulate the eukaryotic cell surface to facilitate their engulfment. Once internalized, they hijack the molecular machinery of the infected cell for their own benefit. At different stages of phagocytosis, particularly during invasion, certain pathogens manipulate pathways governed by small GTPases. In this review, we focus on the role of Rho proteins on curable, sexually transmitted infections caused by Chlamydia trachomatis, Neisseria gonorrhoeae, Trichomonas vaginalis and Treponema pallidum. Despite the high, worldwide frequencies of these sexually-transmitted diseases, very little is known about the strategies developed by these microorganisms to usurp key eukaryotic proteins that control intracellular signaling and actin dynamics. Improved knowledge of these molecular mechanisms will contribute to the elucidation of how these clinically important pathogens manipulate intracellular processes and parasitize their hosts.
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Affiliation(s)
- Cristián A Quintero
- a Laboratory of Phagocytosis and Intracellular Trafficking; IHEM-CONICET; School of Medicine; University of Cuyo ; Mendoza , Argentina
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Amano H, Yamagiwa M, Akao T, Mizuki E, Ohba M, Sakai H. A Novel 29-kDa Crystal Protein fromBacillus thuringiensisInduces Caspase Activation and Cell Death of Jurkat T Cells. Biosci Biotechnol Biochem 2014; 69:2063-72. [PMID: 16306686 DOI: 10.1271/bbb.69.2063] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Bacillus thuringiensis, the most successful and most widely used microbial insecticide, produces crystal proteins. The physiological significance of the crystal proteins is poorly understood except for the potent insecticidal activity. In this paper, we report a novel biological activity of the crystal protein. A 29-kDa crystal protein, p29, produced by B. thuringiensis subsp. coreanensis A1519, was toxic to Jurkat, a cell line from human leukemic T cells. Upon treatment of the Jurkat cells with p29 at a lower concentration, translocation of phosphatidylserine to the external cell surface, release of cytochrome c and Smac/DIABLO from the mitochondria, and activation of caspase-9 were induced. These cellular events were followed by activation of caspase-3, cleavage of poly (ADP-ribose) polymerase (PARP), and chromatin condensation. Peak activation of caspase-9 was prominent and preceded that of caspase-8. Depletion of Bax from the cytosol was observed as the progress of p29-induced cell death. At a higher concentration of p29, the cells showed similar and accelerated morphological change, but neither externalized phosphatidylserine nor caspase-3 activation was observed. These results suggest that p29 at the lower concentration induced cell death of Jurkat accompanied by apotosis-like cellular events, and that mitochondria played a major role in p29-induced cell death.
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Affiliation(s)
- Hiromi Amano
- Graduate School of Natural Science and Technology, Okayama University, Japan
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Jiang H, Liu JK, Wang JD, Lu Y, Zhang M, Yang XH, Hong DJ. The biotoxicity of hydroxyapatite nanoparticles to the plant growth. JOURNAL OF HAZARDOUS MATERIALS 2014; 270:71-81. [PMID: 24556461 DOI: 10.1016/j.jhazmat.2014.01.041] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2013] [Revised: 12/25/2013] [Accepted: 01/22/2014] [Indexed: 06/03/2023]
Abstract
In the present study, hydroxyapatite (HAP) nanoparticles of different particle sizes with high crystallinity and similiar structure were prepared by hydrothermal method. The crystal structure and particle size were characterized by X-ray diffraction pattern (XRD), transmission electron microscopy (TEM) and Fourier transform infrared (FT-IR) spectroscopy. Mung bean sprouts were first used as experimental models. Instead of by MTT assay, the cytoxicity of HAP nanoparticles were proved and evaluated by measuring the hypocotyle length of mung bean sprouts in the culture media. The result showed that the inhibition effect to the growth of mung bean sprouts enhanced when HAP nanoparticles existed. Culture media of HAP nanoparticles with different concentrations and particle sizes was prepared to investigate the level of inhibition effect to the growth of mung bean sprouts. The result found that hypocotyl length of mung bean sprouts were the shortest cultured in 5mg/mL culture media in which the HAP nanoparticles were prepared by hydrothermal method for 24h. It was concluded the inhibition effect depended on the amount of intracellular HAP nanoparticles. The nanostructure and Ca(2+) concentration were considered as the main factors to cause cell apoptosis which was the reason of inhibition. The study provided a preliminary perspective about biotoxicity of HAP nanomaterials to the plant growth.
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Affiliation(s)
- Hao Jiang
- Key Laboratory for Advanced Materials, East China University of Science and Technology, Shanghai 200237 PR China
| | - Jin-Ku Liu
- Key Laboratory for Advanced Materials, East China University of Science and Technology, Shanghai 200237 PR China.
| | - Jian-Dong Wang
- Key Laboratory for Advanced Materials, East China University of Science and Technology, Shanghai 200237 PR China
| | - Yi Lu
- Key Laboratory for Advanced Materials, East China University of Science and Technology, Shanghai 200237 PR China
| | - Min Zhang
- Key Laboratory for Advanced Materials, East China University of Science and Technology, Shanghai 200237 PR China
| | - Xiao-Hong Yang
- Department of Chemistry, Chizhou University, Chizhou 247000, PR China.
| | - Dan-Jing Hong
- Key Laboratory for Advanced Materials, East China University of Science and Technology, Shanghai 200237 PR China
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Saturating mutagenesis of an essential gene: a majority of the Neisseria gonorrhoeae major outer membrane porin (PorB) is mutable. J Bacteriol 2013; 196:540-7. [PMID: 24244002 DOI: 10.1128/jb.01073-13] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
The major outer membrane porin (PorB) of Neisseria gonorrhoeae is an essential protein that mediates ion exchange between the organism and its environment and also plays multiple roles in human host pathogenesis. To facilitate structure-function studies of porin's multiple roles, we performed saturating mutagenesis at the porB locus and used deep sequencing to identify essential versus mutable residues. Random mutations in porB were generated in a plasmid vector, and mutant gene pools were transformed into N. gonorrhoeae to select for alleles that maintained bacterial viability. Deep sequencing of the input plasmid pools and the output N. gonorrhoeae genomic DNA pools identified mutations present in each, and the mutations in both pools were compared to determine which changes could be tolerated by the organism. We examined the mutability of 328 amino acids in the mature PorB protein and found that 308 of them were likely to be mutable and that 20 amino acids were likely to be nonmutable. A subset of these predictions was validated experimentally. This approach to identifying essential amino acids in a protein of interest introduces an additional application for next-generation sequencing technology and provides a template for future studies of both porin and other essential bacterial genes.
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Chander H, Majumdar S, Sapru S, Rishi P. Macrophage Cell Death Due toSalmonella entericaSerovar Typhi and Its Acid Stress Protein Has Features of Apoptosis. Microbiol Immunol 2013; 49:323-30. [PMID: 15840957 DOI: 10.1111/j.1348-0421.2005.tb03736.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Salmonella spp. have been shown to cause apoptosis of various host cell types as a part of their infection process. However, the induction of apoptosis remains to be looked into under the different host environments including acidic stress experienced by the pathogen. In order to simulate the in vivo acidic conditions, we studied the potential of S. typhi and its protein expressed under in vitro acidic conditions to induce apoptosis in macrophages. Murine macrophages were isolated and interacted with serovar Typhi and its acid stress protein for different time periods. The assessment of nucleosomal DNA, and nuclear staining with H-33342 dye and flow cytometry indicated the occurrence of characteristic features of apoptosis. Analysis of data revealed that S. typhi caused apoptotic cell death in 61% of macrophages whereas stress-induced protein alone accounted for apoptotic cell death in 45% of macrophages. The present study, for the first time demonstrates the potential of stress-induced outermembrane component of S. typhi to induce apoptosis. Identification of such factors may offer new insights for understanding the pathophysiology of the disease during the host-pathogen interactions.
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Affiliation(s)
- Harish Chander
- Department of Microbiology, Panjab University, Chandigarh, India
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Jeong SY, Martchenko M, Cohen SN. Calpain-dependent cytoskeletal rearrangement exploited for anthrax toxin endocytosis. Proc Natl Acad Sci U S A 2013; 110:E4007-15. [PMID: 24085852 PMCID: PMC3801034 DOI: 10.1073/pnas.1316852110] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
The protective antigen component of Bacillus anthracis toxins can interact with at least three distinct proteins on the host cell surface, capillary morphogenesis gene 2 (CMG2), tumor endothelial marker 8, and β1-integrin, and, with the assistance of other host proteins, enters targeted cells by receptor-mediated endocytosis. Using an antisense-based phenotypic screen, we discovered the role of calpains in this process. We show that functions of a ubiquitous Ca(2+)-dependent cysteine protease, calpain-2, and of the calpain substrate talin-1 are exploited for association of anthrax toxin and its principal receptor, CMG2, with higher-order actin filaments and consequently for toxin entry into host cells. Down-regulated expression of calpain-2 or talin-1, or pharmacological interference with calpain action, did not affect toxin binding but reduced endocytosis and increased the survival of cells exposed to anthrax lethal toxin. Adventitious expression of wild-type talin-1 promoted toxin endocytosis and lethality, whereas expression of a talin-1 mutant (L432G) that is insensitive to calpain cleavage did not. Disruption of talin-1, which links integrin-containing focal adhesion complexes to the actin cytoskeleton, facilitated association of toxin bound to its principal cell-surface receptor, CMG2, with higher-order actin filaments undergoing dynamic disassembly and reassembly during endocytosis. Our results reveal a mechanism by which a bacterial toxin uses constitutively occurring calpain-mediated cytoskeletal rearrangement for internalization.
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Affiliation(s)
| | | | - Stanley N. Cohen
- Departments of Genetics and
- Medicine, Stanford University School of Medicine, Stanford, CA 94305
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Sakharwade SC, Sharma PK, Mukhopadhaya A. Vibrio cholerae porin OmpU induces pro-inflammatory responses, but down-regulates LPS-mediated effects in RAW 264.7, THP-1 and human PBMCs. PLoS One 2013; 8:e76583. [PMID: 24086753 PMCID: PMC3785423 DOI: 10.1371/journal.pone.0076583] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2013] [Accepted: 08/25/2013] [Indexed: 12/18/2022] Open
Abstract
Vibrio cholerae porin OmpU plays a crucial role in the survival of the organism in the human gut. Various observations suggest critical involvement of OmpU in V. cholerae pathogenesis. However, OmpU is poorly characterized in terms of its ability to evoke cellular responses, particularly in the context of host immune system. Therefore, towards characterizing V. cholerae OmpU for its host immunomodulatory functions, we have studied the ability of OmpU to elicit pro-inflammatory responses in a range of immune cells which include, mouse RAW 264.7 macrophages, human THP-1 monocytes and human PBMCs. We have observed that purified OmpU induces pro-inflammatory responses in terms of production of NO, TNFα and IL-6. Interestingly, pre-treatment of the cells with OmpU suppresses the production of NO, TNFα, IL-6 as well as IL-12 upon subsequent activation with LPS. Our results therefore suggest that V. cholerae OmpU may have a differential regulatory role in terms of host immunomodulatory function: it can induce pro-inflammatory responses in target host immune cells, whereas it can also exert suppressive effect on LPS-induced pro-inflammatory responses. In addition, our study indicates that purified OmpU may have the ability to skew the Th1 response towards the Th2 response, presumably via suppression of IL-12 production.
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Affiliation(s)
- Sanica C Sakharwade
- Department of Biological Sciences, Indian Institute of Science Education and Research (IISER) Mohali, Mohali, Punjab, India
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Kraemer BF, Weyrich AS, Lindemann S. Protein degradation systems in platelets. Thromb Haemost 2013; 110:920-4. [PMID: 24048267 DOI: 10.1160/th13-03-0183] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2013] [Accepted: 07/28/2013] [Indexed: 01/05/2023]
Abstract
Protein synthesis and degradation are essential processes that allow cells to survive and adapt to their surrounding milieu. In nucleated cells, the degradation and/or cleavage of proteins is required to eliminate aberrant proteins. Cells also degrade proteins as a mechanism for cell signalling and complex cellular functions. Although the last decade has convincingly shown that platelets synthesise proteins, the roles of protein degradation in these anucleate cytoplasts are less clear. Here we review what is known about protein degradation in platelets placing particular emphasis on the proteasome and the cysteine protease calpain.
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Affiliation(s)
- B F Kraemer
- Andrew Weyrich, MD, Eccles Institute of Human Genetics, Department of Internal Medicine, University of Utah, Salt Lake City, Building 533 Room 4220, Salt Lake City, Utah 84112, USA, Tel: +1 801 5850702, Fax: +1 801 5850701, E-mail:
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41
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Structure-function studies of the Neisseria gonorrhoeae major outer membrane porin. Infect Immun 2013; 81:4383-91. [PMID: 24042111 DOI: 10.1128/iai.00367-13] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
The major outer membrane porin (PorB) expressed by Neisseria gonorrhoeae plays multiple roles during infection, in addition to its function as an outer membrane pore. We have generated a panel of mutants of N. gonorrhoeae strain FA1090 expressing a variety of mutant porB genes that all function as porins. We identified multiple regions of porin that are involved in its binding to the complement regulatory factors C4b-binding protein and factor H and confirmed that the ability to bind at least one factor is required for FA1090 to survive the bactericidal effects of human serum. We tested the ability of these mutants to inhibit both apoptosis and the oxidative burst in polymorphonuclear leukocytes but were unable to identify the porin domains required for either function. This study has identified nonessential porin domains and some potentially essential portions of the protein and has further expanded our understanding of the contribution of the porin domains required for complement regulation.
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Jadhav SR, Rao KS, Zheng Y, Garavito RM, Worden RM. Voltage dependent closure of PorB class II porin from Neisseria meningitidis investigated using impedance spectroscopy in a tethered bilayer lipid membrane interface. J Colloid Interface Sci 2013; 390:211-6. [PMID: 23083768 DOI: 10.1016/j.jcis.2012.09.031] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2012] [Revised: 09/13/2012] [Accepted: 09/14/2012] [Indexed: 01/16/2023]
Abstract
Electrochemical impedance spectroscopy (EIS) was used to characterize voltage-dependent closure of PorB class II (PorBII) porin from Neisseria meningitidis incorporated in a tethered bilayer lipid membrane (tBLM). The tBLM's lower leaflet was fabricated by depositing a self assembled monolayer (SAM) of 1,2-dipalmitoyl-sn-glycero-3-phosphothioethanol (DPPTE) on a gold electrode, and the upper leaflet was formed by depositing1,2-dioleoyl-sn-glycero-3-phoshocholine (DOPC) liposomes. At 0mV bias DC potential, incorporation of PorBII decreased the membrane resistance (R(m)) from 2.5 MΩc m(2) to 0.6 MΩ cm(2), giving a ΔR(m) of 1.9 MΩ cm(2) and a normalized ΔR(m) (ΔR(m) divided by the R(m) of the tBLM without PorBII) of 76%. When the bias DC potential was increased to 200 mV, the normalized ΔR(m) value decreased to 20%. The effect of applied voltage on ΔR(m) was completely reversible, suggesting voltage-dependent closure of PorBII. The voltage dependence of PorBII was further studied in a planar bilayer lipid membrane made from 1,2-diphytanoyl-sn-glycero-3-phosphocholine (DPhytPC). Following a single insertion event, PorBII exhibited multiple conductance states, with reversible, voltage-dependent closure of PorBII porin occurring at high transmembrane potentials. The trimetric porin closed in three discrete steps, each step corresponding to closure of one conducting monomer unit. The most probable single channel conductance was 4.2 nS. The agreement between results obtained with the tBLM and pBLM platforms demonstrates the utility of EIS to screen channel proteins immobilized in tBLM for voltage-gated behavior.
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Affiliation(s)
- Sachin R Jadhav
- Department of Chemical Engineering and Materials Science, Michigan State University, East Lansing, MI 48824, USA
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Smani Y, Docobo-Pérez F, López-Rojas R, Domínguez-Herrera J, Ibáñez-Martínez J, Pachón J. Platelet-activating factor receptor initiates contact of Acinetobacter baumannii expressing phosphorylcholine with host cells. J Biol Chem 2012; 287:26901-10. [PMID: 22689572 DOI: 10.1074/jbc.m112.344556] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Adhesion is an initial and important step in Acinetobacter baumannii causing infections. However, the exact molecular mechanism of such a step between A. baumannii and the host cells remains unclear. Here, we demonstrated that the phosphorylcholine (ChoP)-containing outer membrane protein of A. baumannii binds to A549 cells through platelet-activating factor receptor (PAFR), resulting in activation of G protein and intracellular calcium. Upon A. baumannii expressing ChoP binding to PAFR, clathrin and β-arrestins, proteins involved in the direction of the vacuolar movement, are activated during invasion of A. baumannii. PAFR antagonism restricts the dissemination of A. baumannii in the pneumonia model. These results define a role for PAFR in A. baumannii interaction with host cells and suggest a mechanism for the entry of A. baumannii into the cytoplasm of host cells.
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Affiliation(s)
- Younes Smani
- Clinic Unit of Infectious Diseases, Microbiology and Preventive Medicine, Institute of Biomedicine of Seville (IBiS), University Hospital Virgen del Rocío/CSIC/University of Seville, 41013 Seville, Spain.
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Jiang JH, Tong J, Gabriel K. Hijacking Mitochondria: Bacterial Toxins that Modulate Mitochondrial Function. IUBMB Life 2012; 64:397-401. [DOI: 10.1002/iub.1021] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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So NSY, Ostrowski MA, Gray-Owen SD. Vigorous response of human innate functioning IgM memory B cells upon infection by Neisseria gonorrhoeae. THE JOURNAL OF IMMUNOLOGY 2012; 188:4008-22. [PMID: 22427638 DOI: 10.4049/jimmunol.1100718] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Neisseria gonorrhoeae, the cause of the sexually transmitted infection gonorrhea, elicits low levels of specific Ig that decline rapidly after the bacteria are cleared. Reinfection with the same serovar can occur, and prior gonococcal infection does not alter the Ig response upon subsequent exposure, suggesting that protective immunity is not induced. The mucosal Ig response apparent during gonorrhea does not correlate with that observed systemically, leading to a suggestion that it is locally generated. In considering whether N. gonorrhoeae directly influences B cells, we observed that gonococcal infection prolonged viability of primary human B cells in vitro and elicited robust activation and vigorous proliferative responses in the absence of T cells. Furthermore, we observed the specific expansion of IgD(+)CD27(+) B cells in response to gonococcal infection. These cells are innate in function, conferring protection against diverse microbes by producing low-affinity, broadly reactive IgM without inducing classical immunologic memory. Although gonococcal infection of B cells produced small amounts of gonococcal-specific IgM, IgM specific for irrelevant Ags were also produced, suggesting a broad, polyspecific Ig response. The gonococci were effectively bound and engulfed by B cells. TLR9-inhibitory CpGs blocked B cell responses, indicating that intracellular bacterial degradation allows for innate immune detection within the phagolysosome. To our knowledge, this is the first report of a bacterial pathogen having specific affinity for the human IgM memory B cells, driving their potent activation and polyclonal Ig response. This unfocused T-independent response explains the localized Ig response that occurs, despite an absence of immunologic memory elicited during gonorrhea.
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Affiliation(s)
- Nancy S Y So
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario M5S 1A8, Canada
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Meningococcal outer membrane protein NhhA triggers apoptosis in macrophages. PLoS One 2012; 7:e29586. [PMID: 22238624 PMCID: PMC3251587 DOI: 10.1371/journal.pone.0029586] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2011] [Accepted: 12/01/2011] [Indexed: 11/19/2022] Open
Abstract
Phagocytotic cells play a fundamental role in the defense against bacterial pathogens. One mechanism whereby bacteria evade phagocytosis is to produce factors that trigger apoptosis. Here we identify for the first time a meningococcal protein capable of inducing macrophage apoptosis. The conserved meningococcal outer membrane protein NhhA (Neisseria hia/hsf homologue A, also known as Hsf) mediates bacterial adhesion and interacts with extracellular matrix components heparan sulphate and laminin. Meningococci lacking NhhA fail to colonise nasal mucosa in a mouse model of meningococcal disease. We found that exposure of macrophages to NhhA resulted in a highly increased rate of apoptosis that proceeded through caspase activation. Exposure of macrophages to NhhA also led to iNOS induction and nitric oxide production. However, neither nitric oxide production nor TNF-α signaling was found to be a prerequisite for NhhA-induced apoptosis. Macrophages exposed to wildtype NhhA-expressing meningococci were also found to undergo apoptosis whereas NhhA-deficient meningococci had a markedly decreased capacity to induce macrophage apoptosis. These data provide new insights on the role of NhhA in meningococcal disease. NhhA-induced macrophage apoptosis could be a mechanism whereby meningococci evade immunoregulatory and phagocytotic actions of macrophages.
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Massari P, Wetzler LM. Analysis of parameters associated with prevention of cellular apoptosis by pathogenic Neisseriae and purified porins. Methods Mol Biol 2012; 799:319-41. [PMID: 21993654 DOI: 10.1007/978-1-61779-346-2_19] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/19/2024]
Abstract
The process of cellular apoptosis is mediated by a number of microbial pathogens to modulate host defense mechanisms. Inhibition of apoptosis is thought to favor microbial survival, replication or immune evasion, while induction of apoptosis is likely to promote escape of the organisms from host cells. Several studies have reported that infection with Neisseria spp. can inhibit or reduce apoptotic cell death, thus allowing adaptation, intracellular replication, and immune evasion, events that are likely to spread infection. In this chapter, various techniques are described for direct measurement of host cell responses to infection with Neisseria meningitidis and to treatment with pure Neisseria porins, the major proteins found in the outer membrane of the pathogen.
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Affiliation(s)
- Paola Massari
- Department of Medicine, Evans BioMedical Research Center, Section of Infectious Diseases, Boston University School of Medicine, Boston, MA, USA.
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Jeoung M, Bridges PJ. Cyclic regulation of apoptotic gene expression in the mouse oviduct. Reprod Fertil Dev 2011; 23:638-44. [PMID: 21635812 DOI: 10.1071/rd11011] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2011] [Accepted: 02/07/2011] [Indexed: 12/14/2022] Open
Abstract
The oviduct is a dynamic structure whose function relies upon cyclic changes in the morphology of both ciliated and secretory luminal epithelial cells. Unfortunately, infection of these epithelial cells by sexually transmitted pathogens can lead to pelvic inflammatory disease, ectopic pregnancies and infertility. The disruption of normal, cyclic apoptosis in the oviducal epithelium appears to be a causal factor of oviducal pathology and therefore, these pathways represent a potential target for diagnosis and therapeutic intervention. The objective of this study was to determine the pattern of expression for apoptotic genes in the oviduct of the naturally cycling mouse, generating fundamental information that can be applied to the development of animal models for research and the identification of targets for disease intervention. Whole oviducts were collected from regular cycling mice killed at 1p.m. on each day of the oestrous cycle and the expression of 84 apoptotic genes determined by targeted PCR super-array. Intact and cleaved caspases were then evaluated by western blotting. The expression of mRNA for genes classified as pro-apoptotic (Bad, Bak1 and Bok) and anti-apoptotic (Bag3, Bnip2 and Xiap) was regulated by day (P < 0.05). Differences in the temporal expression of several p53-related genes (Trp53bp2, Trp53inp1 and Trp73), those specific to the TNF superfamily (Tnfrsf10 and Tnfsf10b) and one caspase (Casp14) were also observed (P < 0.05). The cleaved forms of Caspases-3, -6 and -12 were all detected throughout the oestrous cycle. These results represent the first pathway-wide analysis of apoptotic gene expression in the murine oviduct.
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Affiliation(s)
- Myoungkun Jeoung
- Division of Clinical and Reproductive Sciences, University of Kentucky, Lexington, KY 40536, USA
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Abstract
Chronic spirochetal infection can cause slowly progressive dementia, cortical atrophy and amyloid deposition in the atrophic form of general paresis. There is a significant association between Alzheimer disease (AD) and various types of spirochete (including the periodontal pathogen Treponemas and Borrelia burgdorferi), and other pathogens such as Chlamydophyla pneumoniae and herpes simplex virus type-1 (HSV-1). Exposure of mammalian neuronal and glial cells and organotypic cultures to spirochetes reproduces the biological and pathological hallmarks of AD. Senile-plaque-like beta amyloid (Aβ) deposits are also observed in mice following inhalation of C. pneumoniae in vivo, and Aβ accumulation and phosphorylation of tau is induced in neurons by HSV-1 in vitro and in vivo. Specific bacterial ligands, and bacterial and viral DNA and RNA all increase the expression of proinflammatory molecules, which activates the innate and adaptive immune systems. Evasion of pathogens from destruction by the host immune reactions leads to persistent infection, chronic inflammation, neuronal destruction and Aβ deposition. Aβ has been shown to be a pore-forming antimicrobial peptide, indicating that Aβ accumulation might be a response to infection. Global attention and action is needed to support this emerging field of research because dementia might be prevented by combined antibiotic, antiviral and anti-inflammatory therapy.
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Graewe S, Rankin KE, Lehmann C, Deschermeier C, Hecht L, Froehlke U, Stanway RR, Heussler V. Hostile takeover by Plasmodium: reorganization of parasite and host cell membranes during liver stage egress. PLoS Pathog 2011; 7:e1002224. [PMID: 21909271 PMCID: PMC3164640 DOI: 10.1371/journal.ppat.1002224] [Citation(s) in RCA: 78] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2011] [Accepted: 07/05/2011] [Indexed: 11/27/2022] Open
Abstract
The protozoan parasite Plasmodium is transmitted by female Anopheles mosquitoes and undergoes obligatory development within a parasitophorous vacuole in hepatocytes before it is released into the bloodstream. The transition to the blood stage was previously shown to involve the packaging of exoerythrocytic merozoites into membrane-surrounded vesicles, called merosomes, which are delivered directly into liver sinusoids. However, it was unclear whether the membrane of these merosomes was derived from the parasite membrane, the parasitophorous vacuole membrane or the host cell membrane. This knowledge is required to determine how phagocytes will be directed against merosomes. Here, we fluorescently label the candidate membranes and use live cell imaging to show that the merosome membrane derives from the host cell membrane. We also demonstrate that proteins in the host cell membrane are lost during merozoite liberation from the parasitophorous vacuole. Immediately after the breakdown of the parasitophorous vacuole membrane, the host cell mitochondria begin to degenerate and protein biosynthesis arrests. The intact host cell plasma membrane surrounding merosomes allows Plasmodium to mask itself from the host immune system and bypass the numerous Kupffer cells on its way into the bloodstream. This represents an effective strategy for evading host defenses before establishing a blood stage infection. Malaria is one of the most important infectious diseases in the developing world. It is caused by Plasmodium parasites, which are transmitted by female Anopheles mosquitoes during blood feeding. In the mammalian host, Plasmodium first develops within liver cells, growing from one parasite into many thousands. After this extensive replication, the parasites are released into the blood stream in vesicles termed merosomes that are surrounded by membrane. However, the origin of this membrane was unclear due to the absence of typical host cell membrane markers. Here, we analyzed several parasite- and host cell-derived membranes and show that the merosome membrane is of host cell origin. We also demonstrate that characteristic markers are lost from the host cell membrane once the parasite is liberated from its enclosure within the cell and moves freely in the host cell. The disappearance of membrane markers seems to be a consequence of the host cell death that is triggered toward the end of parasite development in the liver cell. The simultaneous induction of host cell death and retention of an intact host cell membrane enables the Plasmodium parasite to hide from the host immune system and thus to escape elimination before establishing a blood stage infection.
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Affiliation(s)
- Stefanie Graewe
- Malaria Lab I, Department of Molecular Parasitology, Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany.
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