Community Development between
                    Porphyromonas gingivalis
                    and
                    Candida albicans
                    Mediated by InlJ and Als3

ABSTRACT The pleiomorphic yeast Candida albicans is a significant pathogen in immunocompromised individuals. In the oral cavity, C. albicans is an inhabitant of polymicrobial communities, and interspecies interactions promote hyphal formation and biofilm formation. C. albicans colonizes the subgingival area, and the frequency of colonization increases in periodontal disease. In this study, we investigated the interactions between C. albicans and the periodontal pathogen Porphyromonas gingivalis . C. albicans and P. gingivalis were found to coadhere in both the planktonic and sessile phases. Loss of the internalin-family protein InlJ abrogated adhesion of P. gingivalis to C. albicans , and recombinant InlJ protein competitively inhibited interspecies binding. A mutant of C. albicans deficient in expression of major hyphal protein Als3 showed diminished binding to P. gingivalis , and InlJ interacted with Als3 heterologously expressed in Saccharomyces cerevisiae . Transcriptional profiling by RNA sequencing (RNA-Seq) established that 57 genes were uniquely upregulated in an InlJ-dependent manner in P. gingivalis - C. albicans communities, with overrepresentation of those corresponding to 31 gene ontology terms, including those associated with growth and division. Of potential relevance to the disease process, C. albicans induced upregulation of components of the type IX secretion apparatus. Collectively, these findings indicate that InlJ-Als3-dependent binding facilitates interdomain community development between C. albicans and P. gingivalis and that P. gingivalis has the potential for increased virulence within such communities. IMPORTANCE Many diseases involve the concerted actions of microorganisms assembled in polymicrobial communities. Inflammatory periodontal diseases are among the most common infections of humans and result in destruction of gum tissue and, ultimately, in loss of teeth. In periodontal disease, pathogenic communities can include the fungus Candida albicans ; however, the contribution of C. albicans to the synergistic virulence of the community is poorly understood. Here we characterize the interactions between C. albicans and the keystone bacterial pathogen Porphyromonas gingivalis and show that coadhesion mediated by specific proteins results in major changes in gene expression by P. gingivalis , which could serve to increase pathogenic potential. The work provides significant insights into interdomain interactions that can enhance our understanding of diseases involving a multiplicity of microbial pathogens.

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Draft Whole-Genome Sequences of Periodontal Pathobionts Porphyromonas gingivalis, Prevotella intermedia, and Tannerella forsythia Contain Phase-Variable Restriction-Modification Systems

Genome Announcements ◽

10.1128/genomea.01229-17 ◽

2017 ◽

Vol 5 (46) ◽

Cited By ~ 3

Author(s):

Richard D. Haigh ◽

Liam A. Crawford ◽

Joseph D. Ralph ◽

Joseph J. Wanford ◽

Sonia R. Vartoukian ◽

...

Keyword(s):

Periodontal Disease ◽

Porphyromonas Gingivalis ◽

Disease Process ◽

Oral Bacteria ◽

Host Responses ◽

Prevotella Intermedia ◽

Phase Variable ◽

Genome Sequences ◽

Tannerella Forsythia ◽

Content Type

ABSTRACT Periodontal disease comprises mild to severe inflammatory host responses to oral bacteria that can cause destruction of the tooth-supporting tissue. We report genome sequences for 18 clinical isolates of Porphyromonas gingivalis, Prevotella intermedia, and Tannerella forsythia, Gram-negative obligate anaerobes that play a role in the periodontal disease process.

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In VitroAnalyses of the Effects of Heparin and Parabens on Candida albicans Biofilms and Planktonic Cells

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.05061-11 ◽

2011 ◽

Vol 56 (1) ◽

pp. 148-153 ◽

Cited By ~ 15

Author(s):

Marisa H. Miceli ◽

Stella M. Bernardo ◽

T. S. Neil Ku ◽

Carla Walraven ◽

Samuel A. Lee

Keyword(s):

Candida Albicans ◽

Metabolic Activity ◽

Biofilm Formation ◽

High Dose ◽

Dependent Manner ◽

Planktonic Cells ◽

Content Type ◽

Heparin Sodium ◽

The Individual

ABSTRACTInfections and thromboses are the most common complications associated with central venous catheters. Suggested strategies for prevention and management of these complications include the use of heparin-coated catheters, heparin locks, and antimicrobial lock therapy. However, the effects of heparin onCandida albicansbiofilms and planktonic cells have not been previously studied. Therefore, we sought to determine thein vitroeffect of a heparin sodium preparation (HP) on biofilms and planktonic cells ofC. albicans. Because HP contains two preservatives, methyl paraben (MP) and propyl paraben (PP), these compounds and heparin sodium without preservatives (Pure-H) were also tested individually. The metabolic activity of the mature biofilm after treatment was assessed using XTT [2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide] reduction and microscopy. Pure-H, MP, and PP caused up to 75, 85, and 60% reductions of metabolic activity of the mature preformedC. albicansbiofilms, respectively. Maximal efficacy against the mature biofilm was observed with HP (up to 90%) compared to the individual compounds (P< 0.0001). Pure-H, MP, and PP each inhibitedC. albicansbiofilm formation up to 90%. A complete inhibition of biofilm formation was observed with HP at 5,000 U/ml and higher. When tested against planktonic cells, each compound inhibited growth in a dose-dependent manner. These data indicated that HP, MP, PP, and Pure-H havein vitroantifungal activity againstC. albicansmature biofilms, formation of biofilms, and planktonic cells. Investigation of high-dose heparin-based strategies (e.g., heparin locks) in combination with traditional antifungal agents for the treatment and/or prevention ofC. albicansbiofilms is warranted.

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Masking of β(1-3)-Glucan in the Cell Wall of Candida albicans from Detection by Innate Immune Cells Depends on Phosphatidylserine

Infection and Immunity ◽

10.1128/iai.01612-14 ◽

2014 ◽

Vol 82 (10) ◽

pp. 4405-4413 ◽

Cited By ~ 32

Author(s):

Sarah E. Davis ◽

Alex Hopke ◽

Steven C. Minkin ◽

Anthony E. Montedonico ◽

Robert T. Wheeler ◽

...

Keyword(s):

Cell Wall ◽

Candida Albicans ◽

De Novo ◽

Invasive Disease ◽

Innate Immune ◽

Dependent Manner ◽

Content Type ◽

Immune Effector ◽

Host Interactions ◽

Innate Immune Effector

ABSTRACTThe virulence ofCandida albicansin a mouse model of invasive candidiasis is dependent on the phospholipids phosphatidylserine (PS) and phosphatidylethanolamine (PE). Disruption of the PS synthase geneCHO1(i.e.,cho1Δ/Δ) eliminates PS and blocks thede novopathway for PE biosynthesis. In addition, thecho1Δ/Δ mutant's ability to cause invasive disease is severely compromised. Thecho1Δ/Δ mutant also exhibits cell wall defects, and in this study, it was determined that loss of PS results in decreased masking of cell wall β(1-3)-glucan from the immune system. In wild-typeC. albicans, the outer mannan layer of the wall masks the inner layer of β(1-3)-glucan from exposure and detection by innate immune effector molecules like the C-type signaling lectin Dectin-1, which is found on macrophages, neutrophils, and dendritic cells. Thecho1Δ/Δ mutant exhibits increases in exposure of β(1-3)-glucan, which leads to greater binding by Dectin-1 in both yeast and hyphal forms. The unmasking of β(1-3)-glucan also results in increased elicitation of TNF-α from macrophages in a Dectin-1-dependent manner. The role of phospholipids in fungal pathogenesis is an emerging field, and this is the first study showing that loss of PS inC. albicansresults in decreased masking of β(1-3)-glucan, which may contribute to our understanding of fungus-host interactions.

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Glycation of Host Proteins Increases Pathogenic Potential of Porphyromonas gingivalis

International Journal of Molecular Sciences ◽

10.3390/ijms222112084 ◽

2021 ◽

Vol 22 (21) ◽

pp. 12084

Author(s):

Michał Śmiga ◽

John W. Smalley ◽

Paulina Ślęzak ◽

Jason L. Brown ◽

Klaudia Siemińska ◽

...

Keyword(s):

Porphyromonas Gingivalis ◽

Biofilm Formation ◽

Disease Process ◽

Human Keratinocytes ◽

Bacterial Biofilm ◽

Pathogenic Potential ◽

Glycated Proteins ◽

Sds Page

The non-enzymatic addition of glucose (glycation) to circulatory and tissue proteins is a ubiquitous pathophysiological consequence of hyperglycemia in diabetes. Given the high incidence of periodontitis and diabetes and the emerging link between these conditions, it is of crucial importance to define the basic virulence mechanisms employed by periodontopathogens such as Porphyromonas gingivalis in mediating the disease process. The aim of this study was to determine whether glycated proteins are more easily utilized by P. gingivalis to stimulate growth and promote the pathogenic potential of this bacterium. We analyzed the properties of three commonly encountered proteins in the periodontal environment that are known to become glycated and that may serve as either protein substrates or easily accessible heme sources. In vitro glycated proteins were characterized using colorimetric assays, mass spectrometry, far- and near-UV circular dichroism and UV–visible spectroscopic analyses and SDS-PAGE. The interaction of glycated hemoglobin, serum albumin and type one collagen with P. gingivalis cells or HmuY protein was examined using spectroscopic methods, SDS-PAGE and co-culturing P. gingivalis with human keratinocytes. We found that glycation increases the ability of P. gingivalis to acquire heme from hemoglobin, mostly due to heme sequestration by the HmuY hemophore-like protein. We also found an increase in biofilm formation on glycated collagen-coated abiotic surfaces. We conclude that glycation might promote the virulence of P. gingivalis by making heme more available from hemoglobin and facilitating bacterial biofilm formation, thus increasing P. gingivalis pathogenic potential in vivo.

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Dectin-1 Stimulation of Hematopoietic Stem and Progenitor Cells Occurs In Vivo and Promotes Differentiation Toward Trained Macrophages via an Indirect Cell-Autonomous Mechanism

mBio ◽

10.1128/mbio.00781-20 ◽

2020 ◽

Vol 11 (3) ◽

Cited By ~ 1

Author(s):

Cristina Bono ◽

Alba Martínez ◽

Javier Megías ◽

Daniel Gozalbo ◽

Alberto Yáñez ◽

...

Keyword(s):

Bone Marrow ◽

Candida Albicans ◽

Progenitor Cells ◽

Recipient Mouse ◽

Dependent Manner ◽

Toll Like Receptor ◽

Hematopoietic Stem ◽

Content Type ◽

Stem And Progenitor Cells

ABSTRACT Toll-like receptor (TLR) agonists drive hematopoietic stem and progenitor cells (HSPCs) to differentiate along the myeloid lineage. In this study, we used an HSPC transplantation model to investigate the possible direct interaction of β-glucan and its receptor (dectin-1) on HSPCs in vivo. Purified HSPCs from bone marrow of B6Ly5.1 mice (CD45.1 alloantigen) were transplanted into dectin-1−/− mice (CD45.2 alloantigen), which were then injected with β-glucan (depleted zymosan). As recipient mouse cells do not recognize the dectin-1 agonist injected, interference by soluble mediators secreted by recipient cells is negligible. Transplanted HSPCs differentiated into macrophages in response to depleted zymosan in the spleens and bone marrow of recipient mice. Functionally, macrophages derived from HSPCs exposed to depleted zymosan in vivo produced higher levels of inflammatory cytokines (tumor necrosis factor alpha [TNF-α] and interleukin 6 [IL-6]). These results demonstrate that trained immune responses, already described for monocytes and macrophages, also take place in HSPCs. Using a similar in vivo model of HSPC transplantation, we demonstrated that inactivated yeasts of Candida albicans induce differentiation of HSPCs through a dectin-1- and MyD88-dependent pathway. Soluble factors produced following exposure of HSPCs to dectin-1 agonists acted in a paracrine manner to induce myeloid differentiation and to influence the function of macrophages derived from dectin-1-unresponsive or β-glucan-unexposed HSPCs. Finally, we demonstrated that an in vitro transient exposure of HSPCs to live C. albicans cells, prior to differentiation, is sufficient to induce a trained phenotype of the macrophages they produce in a dectin-1- and Toll-like receptor 2 (TLR2)-dependent manner. IMPORTANCE Invasive candidiasis is an increasingly frequent cause of serious and often fatal infections. Understanding host defense is essential to design novel therapeutic strategies to boost immune protection against Candida albicans. In this article, we delve into two new concepts that have arisen over the last years: (i) the delivery of myelopoiesis-inducing signals by microbial components directly sensed by hematopoietic stem and progenitor cells (HSPCs) and (ii) the concept of “trained innate immunity” that may also apply to HSPCs. We demonstrate that dectin-1 ligation in vivo activates HSPCs and induces their differentiation to trained macrophages by a cell-autonomous indirect mechanism. This points to new mechanisms by which pathogen detection by HSPCs may modulate hematopoiesis in real time to generate myeloid cells better prepared to deal with the infection. Manipulation of this process may help to boost the innate immune response during candidiasis.

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Targeting the HUβ Protein PreventsPorphyromonas gingivalisfrom Entering into Preexisting Biofilms

Journal of Bacteriology ◽

10.1128/jb.00790-17 ◽

2018 ◽

Vol 200 (11) ◽

pp. e00790-17 ◽

Cited By ~ 4

Author(s):

Christopher J. Rocco ◽

Lauren O. Bakaletz ◽

Steven D. Goodman

Keyword(s):

Oral Cavity ◽

Periodontal Disease ◽

Porphyromonas Gingivalis ◽

The United States ◽

Extracellular Dna ◽

Bacterial Biofilms ◽

Oral Streptococci ◽

Content Type ◽

Oral Streptococcus ◽

Streptococcal Species

ABSTRACTThe oral cavity is home to a wide variety of bacterial species, both commensal, such as various streptococcal species, and pathogenic, such asPorphyromonas gingivalis, one of the main etiological agents of periodontal disease. Our understanding of how these bacteria ultimately cause disease is highly dependent upon understanding how they coexist and interact with one another in biofilm communities and the mechanisms by which biofilms are formed. Our research has demonstrated that the DNABII family of DNA-binding proteins are important components of the extracellular DNA (eDNA)-dependent matrix of bacterial biofilms and that sequestering these proteins via protein-specific antibodies results in the collapse of the biofilm structure and release of the resident bacteria. While the high degree of similarity among the DNABII family of proteins has allowed antibodies derived against specific DNABII proteins to disrupt biofilms formed by a wide range of bacterial pathogens, the DNABII proteins ofP. gingivalishave proven to be antigenically distinct, allowing us to determine if we can use anti-P. gingivalisHUβ antibodies to specifically target this species for removal from a mixed-species biofilm. Importantly, despite forming homotypic biofilmsin vitro,P. gingivalismust enter preexisting biofilmsin vivoin order to persist within the oral cavity. The data presented here indicate that antibodies derived against theP. gingivalisDNABII protein, HUβ, reduce by half the amount ofP. gingivalisorganisms entering into preexisting biofilm formed by four oral streptococcal species. These results support our efforts to develop methods for preventing and treating periodontal disease.IMPORTANCEPeriodontitis is one of the most prevalent chronic infections, affecting 40 to 50% of the population of the United States. The root cause of periodontitis is the presence of bacterial biofilms within the gingival space, withPorphyromonas gingivalisbeing strongly associated with the development of the disease. Periodontitis also increases the risk of secondary conditions and infections such as atherosclerosis and infective endocarditis caused by oral streptococci. To induce periodontitis,P. gingivalisneeds to incorporate into preformed biofilms, with oral streptococci being important binding partners. Our research demonstrates that targeting DNABII proteins with an antibody disperses oral streptococcus biofilm and preventsP. gingivalisentry into oral streptococcus biofilm. These results suggest potential therapeutic treatments for endocarditis caused by streptococci as well as periodontitis.

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Cysteine Proteases of Porphyromonas Gingivalis

Critical Reviews in Oral Biology & Medicine ◽

10.1177/10454411010120030101 ◽

2001 ◽

Vol 12 (3) ◽

pp. 192-216 ◽

Cited By ~ 110

Author(s):

M.A. Curtis ◽

J. Aduse-Opoku ◽

M. Rangarajan

Keyword(s):

Porphyromonas Gingivalis ◽

Translational Control ◽

Research Effort ◽

Periodontal Diseases ◽

Disease Process ◽

Cysteine Proteases ◽

Survival Strategies ◽

Virulence Determinants

The cysteine proteases of Porphyromonas gingivalis are extracellular products of an important etiological agent in periodontal diseases. Many of the in vitro actions of these enzymes are consistent with the observed deregulated inflammatory and immune features of the disease. They are significant targets of the immune responses of affected individuals and are viewed by some as potential molecular targets for therapeutic approaches to these diseases. Furthermore, they appear to represent a complex group of genes and protein products whose transcriptional and translational control and maturation pathways may have a broader relevance to virulence determinants of other persistent bacterial pathogens of human mucosal surfaces. As a result, the genetics, chemistry, and virulence-related properties of the cysteine proteases of P. gingivalis have been the focus of much research effort over the last ten years. In this review, we describe some of the progress in their molecular characterization and how their putative biological roles, in relation to the in vivo growth and survival strategies of P. gingivalis, may also contribute to the periodontal disease process.

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Clathrin- and Arp2/3-Independent Endocytosis in the Fungal Pathogen Candida albicans

mBio ◽

10.1128/mbio.00476-13 ◽

2013 ◽

Vol 4 (5) ◽

Cited By ~ 20

Author(s):

Elias Epp ◽

Elena Nazarova ◽

Hannah Regan ◽

Lois M. Douglas ◽

James B. Konopka ◽

...

Keyword(s):

Candida Albicans ◽

Membrane Proteins ◽

Fungal Pathogen ◽

Mammalian Cells ◽

Fluid Phase ◽

Fungal Species ◽

Endocytic Pathway ◽

Dependent Manner ◽

Content Type ◽

Actin Cables

ABSTRACT Clathrin-mediated endocytosis (CME) is conserved among eukaryotes and has been extensively analyzed at a molecular level. Here, we present an analysis of CME in the human fungal pathogen Candida albicans that shows the same modular structure as those in other fungi and mammalian cells. Intriguingly, C. albicans is perfectly viable in the absence of Arp2/3, an essential component of CME in other systems. In C. albicans, Arp2/3 function remains essential for CME as all 15 proteins tested that participate in CME, including clathrin, lose their characteristic dynamics observed in wild-type (WT) cells. However, since arp2/3 cells are still able to endocytose lipids and fluid-phase markers, but not the Ste2 and Mup1 plasma membrane proteins, there must be an alternate clathrin-independent pathway we term Arp2/3-independent endocytosis (AIE). Characterization of AIE shows that endocytosis in arp2 mutants relies on actin cables and other Arp2/3-independent actin structures, as inhibition of actin functions prevented cargo uptake in arp2/3 mutants. Transmission electron microscopy (TEM) showed that arp2/3 mutants still formed invaginating tubules, cell structures whose proper functions are believed to heavily rely on Arp2/3. Finally, Prk1 and Sjl2, two proteins involved in patch disassembly during CME, were not correctly localized to sites of endocytosis in arp2 mutants, implying a role of Arp2/3 in CME patch disassembly. Overall, C. albicans contains an alternative endocytic pathway (AIE) that relies on actin cable function to permit clathrin-independent endocytosis (CIE) and provides a system to further explore alternate endocytic routes that likely exist in fungal species. IMPORTANCE There is a well-established process of endocytosis that is generally used by eukaryotic cells termed clathrin-mediated endocytosis (CME). Although the details are somewhat different between lower and higher eukaryotes, CME appears to be the dominant endocytic process in all eukaryotes. While fungi such as Saccharomyces cerevisiae have proven excellent models for dissecting the molecular details of endocytosis, loss of CME is so detrimental that it has been difficult to study alternate pathways functioning in its absence. Although the fungal pathogen Candida albicans has a CME pathway that functions similarly to that of S. cerevisiae, inactivation of this pathway does not compromise growth of yeast-form C. albicans. In these cells, lipids and fluid-phase molecules are still endocytosed in an actin-dependent manner, but membrane proteins are not. Thus, C. albicans provides a powerful model for the analysis of CME-independent endocytosis in lower eukaryotes.

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Investigating the Function of Ddr48p in Candida albicans

Eukaryotic Cell ◽

10.1128/ec.00107-12 ◽

2012 ◽

Vol 11 (6) ◽

pp. 718-724 ◽

Cited By ~ 4

Author(s):

I. A. Cleary ◽

N. B. MacGregor ◽

S. P. Saville ◽

D. P. Thomas

Keyword(s):

Candida Albicans ◽

Biofilm Formation ◽

The United States ◽

Pathogenic Potential ◽

Content Type ◽

General Stress Response ◽

Damage Response ◽

Sense And Respond ◽

Immune Defects

ABSTRACTCandidiasis now represents the fourth most frequent nosocomial infection both in the United States and worldwide.Candida albicansis an increasingly common threat to human health as a consequence of AIDS, steroid therapy, organ and tissue transplantation, cancer therapy, broad-spectrum antibiotics, and other immune defects. The pathogenic potential ofC. albicansis intimately related to certain key processes, including biofilm formation and filamentation. Ddr48p is a damage response protein that is significantly upregulated during both biofilm formation and filamentation, but its actual function is unknown. Previous studies have indicated that this protein may be essential inC. albicansbut notSaccharomyces cerevisiae. Here we examined the function of Ddr48p and investigated the role of this protein in biofilm formation and filamentation. We demonstrated that this protein is not essential inC. albicansand appears to be dispensable for filamentation. However,DDR48is required for the flocculation response stimulated by 3-aminotriazole-induced amino acid starvation. Furthermore, we examined the response of this deletion strain to a wide variety of environmental stressors and antifungal compounds. We observed several mild sensitivity or resistance phenotypes and also found that Ddr48p contributes to the DNA damage response ofC. albicans. The results of this study reveal that the role of this highly expressed protein goes beyond a general stress response and impinges on a key facet of pathogenesis, namely, the ability to sense and respond to changes in the host environment.

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MICRO BIOLOGY OF PERIODONTAL DISEASE- A REVIEW

International Journal of Medical Science and Diagnosis Research ◽

10.32553/ijmsdr.v5i6.808 ◽

2021 ◽

Vol 5 (6) ◽

Author(s):

Jageer Chinna ◽

Jannat Sharma

Keyword(s):

Periodontal Disease ◽

Periodontal Diseases ◽

Disease Process ◽

Fusobacterium Nucleatum ◽

Host Cells ◽

Bacterial Invasion ◽

Periodontal Pathogens ◽

Tissue Destruction ◽

Campylobacter Rectus ◽

Periodontal Tissues

Periodontal diseases are inflammatory and destructive diseases of the dentogingival complex associated with specific periodontal pathogens inhabiting periodontal pockets. Periodontal diseases lead to damage of the periodontal tissues supporting the teeth (bone and connective tissue) and affect the quality of life of the affected individuals: poor alimentation, tooth loss, social and financial problems. Although it is generally considered that the disease has multifactorial etiology, data show that some specific Gram-negative microorganisms in the subgingival plaque biofilm play a major role in the initiation and progression of periodontitis. Porphyromonas gingivalis, Treponema denticola and Tannerella forsythia form a consortium in the subgingival biofilm and are regarded as the principal periodontopathogenic bacteria. Other microorganisms that have been implicated as predominant species in the disease process are: Aggregatibacter actinomycetemcomitans, Fusobacterium nucleatum, Prevotella intermedia, Campylobacter rectus, Peptostreptococcus migros, Eikenella corrodens. In periodontitis, the initiation of the disease is the colonization of the tissues by these pathogenic species. The next step is bacterial invasion or invasion by pathogenic products into the periodontal tissues, interactions of bacteria or their substances with host cells, and this directly/indirectly causes degradation of the periodontium, resulting in tissue destruction. Keywords: periodontal disease, periodontal pathogens, microbiology.

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