Oral Biology and Oral Pathology Commons^™

Multiple Factors Regulate The Expression Of Sufcdsub In Streptococcus Mutans, Kassapa Ellepola, Lauren C. Guillot, Bradley Comeaux, Yiran Han, Jessica K. Kajfasz, Jacob P. Bitoun, Grace Spatafora, Jose A. Lemos, Zezhang T. Wen

School of Dentistry Faculty Publications

Introduction: The sufCDSUB gene cluster, encoding the sole iron-sulfur (Fe-S) cluster assembly system in S. mutans, was recently shown to be up-regulated in response to oxidative stressors and Fe limitation. Methods: In this study, luciferase reporter fusion assays, electrophoretic gel mobility shift assays (EMSA) and in vitro transcription assays (IVT) were used to dissect the cis- and trans-acting factors that regulate the expression of sufCDSUB. Results and discussion: Results showed deletion of perR, for the only Fur-family transcriptional regulator in S. mutans, resulted in > 5-fold increases in luciferase activity under the control of the sufCDSUB promoter (P < 0.01), as compared to the parent strain, UA159 when the reporter strains were grown in medium with no supplemental iron. Site-directed mutagenesis of a PerR-box in the promoter region led to elevation of the reporter activity by >1.6-fold (P < 0.01). In an EMSA, recombinant PerR (rPerR) was shown to bind to the cognate sufCDSUB promoter leading to mobility retardation. On the other hand, the reporter activity was increased by > 84-fold …

Addendum: A Small Molecule Produced By Lactobacillus Species Blocks Candida Albicans Filamentation By Inhibiting A Dyrk1-Family Kinase, Jessie Macalpine, Martin Daniel-Ivad, Zhongle Liu, Junko Yano, Nicole M. Revie, Robert T. Todd, Peter J. Stogios, Hiram Sanchez, Teresa R. O'Meara, Thomas A. Tompkins, Alexei Savchenko, Anna Selmecki, Amanda O. Veri, David R. Andes, Paul L. Fidel, Nicole Robbins, Justin Nodwell, Luke Whitesell, Leah E. Cowen

School of Dentistry Faculty Publications

No abstract provided.

Association Of F. Alocis And D. Pneumosintes With Periodontitis Disease Severity And Red Complex Bacteria, Hawaabi F.M. Shaikh, Pratima U. Oswal, Manohar Suresh Kugaji, Sandeep S. Katti, Kishore Gajanan Bhat, Eswar Kandaswamy, Vinayak M. Joshi

School of Dentistry Faculty Publications

Oral biofilms are considered the principal etiological agent in the development of periodontitis. Novel species that may contribute to periodontitis and dysbiosis have been identified recently. The study aims to evaluate the presence of F. alocis and D. pneumosintes in healthy and diseased patients and their association with clinical parameters and with red complex bacteria. The study included 60 subjects, with 30 patients each in the healthy and periodontitis groups. The clinical parameters were noted, and samples were subjected to DNA extraction followed by a polymerase chain reaction. Statistical analysis was performed using the Graph Pad Prism software. Results: F. …

The Impact Of Gestational Diabetes Mellitus And Maternal Oral Microbiome: A Scoping Review, Jaclyn P. Langan

Honors Undergraduate Theses

Background: Gestational diabetes mellitus (GDM) is a common pregnancy-related metabolic disorder associated with adverse maternal and fetal outcomes. Recent research has highlighted the potential role of the oral microbiome in the pathophysiology of various systemic conditions, including diabetes mellitus. However, the impact of GDM on the maternal oral microbiome remains relatively understudied. Understanding alterations in the oral microbiome during pregnancy complicated by GDM could provide valuable insights into the mechanistic links between systemic metabolic disorders and oral health.

Objective: The objective of this scoping review was to comprehensively examine the existing literature on the relationship between GDM and maternal oral …

S. Gordonii-Produced Hydrogen Peroxide Modulates Mir-663a And Ccl20 Expression In Oral Epithelial Cells, Marshall Houston Maynard

Theses and Dissertations--Medical Sciences

The mechanisms through which a persistent recognition of commensal bacteria by oral epithelial cells (OECs) mitigates an uncontrolled inflammatory response of the oral mucosa remain unknown. CCL20 secretion by OECs in response to pathogenic bacteria is regulated by S. gordonii (Sg)-induced miR-663a; nevertheless, the mechanisms involved in these Sg-modulated responses remain to be elucidated. Since Sg is a hydrogen peroxide (H₂O₂) producer, and H₂O₂ has been shown to stimulate miRNA expression, we hypothesized that H₂O₂ could be involved in Sg-induced miR663a and CCL20 responses. Expression of miR663a …

Comparisons Of Oral, Intestinal, And Pancreatic Bacterial Microbiomes In Patients With Pancreatic Cancer And Other Gastrointestinal Diseases, Mei Chung, Naisi Zhao, Richard Meier, Devin C. Koestler, Guojun Wu, Erika De Castillo, Bruce J. Paster, Kevin Charpentier, Jacques Izard, Karl T. Kelsey, Dominique S. Michaud

Department of Food Science and Technology: Faculty Publications

Background: Oral microbiota is believed to play important roles in systemic diseases, including cancer. Methods: We collected oral samples (tongue, buccal, supragingival, and saliva) and pancreatic tissue or intestinal samples from 52 subjects, and characterized 16S rRNA genes using high-throughput DNA sequencing.

Results: Bray–Curtis plot showed clear separations between bacterial communities in the oral cavity and those in intestinal and pancreatic tissue samples. PERMANOVA tests indicated that bacterial communities from buccal samples were similar to supragingival and saliva samples, and pancreatic duct samples were similar to pancreatic tumor samples, but all other samples were significantly different from each …

Porphyromonas Gingivalis Gingipains Induce A Pro-Inflammatory Extracellular Microenvironment : The Role Of Par-2 And Fibronectin., Jeffrey S. Marschall

Electronic Theses and Dissertations

Periodontitis is a chronic inflammatory disease that is characterized by severe tissue destruction of the gingiva and other tooth supporting structures; if left untreated, tooth loss and disintegration of the alveolar bone occurs. This chronic inflammatory state has been linked to other systemic diseases such as cardiovascular disease, diabetes, rheumatoid arthritis, and Alzheimer’s disease. Porphyromonas gingivalis is the major pathogenic microbe in periodontitis. The main virulence factors of P. gingivalis are the Arg-aa and Lys-aa gingipains, which are proteolytic enzymes implicated in a plethora of activities that allow P. gingivalis to subvert the human immune system in the oral cavity …

Correlation Of Periodontal Pathogens In Concurrent Endodontic-Periodontal Diseases, Amela Lačević, Federico Foschi, Lejla Pojskić, Naris Pojskić, Kasim Bajrović, Jacques Izard

Department of Food Science and Technology: Faculty Publications

Objectives: This study investigated the correlation between Tannerella forsythia, Porphyromonas gingivalis, Fusobacterium nucleatum, and Aggregatibacter actinomycetemcomitans at dual sites in concurrent endodonticperiodontal diseases.

Material and methods: Samples were collected from endodontium and periodontium in cases of concurrent endodontic-periodontal diseases from thirty participants. The sensitivity and specificity of SYBR Green real-time PCR was used to identify the targeted species. Absolute number of targeted genome copies in tested samples were extrapolated from respective calibration curve.

Results: No statistical difference was found in the number of detected endodontic-periodontal pathogens between the endodontium and periodontium. The Pearson test …

Identification Of Transcription Factors Gzf3, Rfx1, Orf19.3928 As Being Implicated In Candida-Bacterial Interactions., Joni Watson

Undergraduate Honors Theses

Candida albicans is an opportunistic pathogen that is present in the normal flora in a majority of individuals. One key factor in C. albicans virulence is the ability to change its morphology from yeast to an elongated or hyphal form. The regulation of this morphogenesis relies in part upon quorum sensing (QS) molecules. C. albicans often exists as part of a mixed culture alongside other microbes and is influenced by their presence as well as the presence of QS molecules that they produce. In this study, a library of diploid homozygous transcriptional regulator knockout (TRKO) mutants were screened to identify …

Microbiota, Oral Microbiome, And Pancreatic Cancer, Dominique S. Michaud, Jacques Izard

Department of Food Science and Technology: Faculty Publications

Only 30% of patients diagnosed with pancreatic cancer survive one year post-diagnosis. Progress in understanding the causes of pancreatic cancer has been made, including solidifying the associations with obesity and diabetes, and a proportion of cases should be preventable through lifestyle modifications. Unfortunately, identifying reliable biomarkers of early pancreatic cancer has been extremely challenging, and no effective screening modality is currently available for this devastating form of cancer. Recent data suggest the microbiota may play a role in the disease process, but many questions remain. Future studies focusing on the human microbiome, both etiologically and as a marker of disease …

Neisseria Oralis Sp. Nov., Isolated From Healthy Gingival Plaque And Clinical Samples, William J. Wolfgang, Teresa V. Passaretti, Reashma Jose, Jocelyn Cole, An Coorevits, Andrea N. Carpenter, Sherly Jose, Anita Van Landschoot, Jacques Izard, Donna J. Kohlerschmidt, Peter Vandamme, Floyd E. Dewhirst, Mark A. Fisher, Kimberlee A. Musser

Department of Food Science and Technology: Faculty Publications

A polyphasic analysis was undertaken of seven independent isolates of gram-negative cocci collected from pathological clinical samples from New York, Louisiana, Florida, and Illinois and healthy subgingival plaque from a patient in Virginia, USA. The 16S rRNA gene sequence similarity among these isolates was 99.7–100 %, and the closest species with a validly published name was Neisseria lactamica (96.9 % similarity to the type strain). DNA–DNA hybridization confirmed that these isolates are of the same species and are distinct from their nearest phylogenetic neighbor, N. lactamica. Phylogenetic analysis of 16S and 23S rRNA gene sequences indicated that the …

Composition Of The Adult Digestive Tract Bacterial Microbiome Based On Seven Mouth Surfaces, Tonsils, Throat And Stool Samples, Nicola Segata, Susan Kinder Haake, Peter Mannon, Katherine P. Lemon, Levi Waldron, Dirk Gevers, Curtis Huttenhower, Jacques Izard

Department of Food Science and Technology: Faculty Publications

Background: To understand the relationship between our bacterial microbiome and health, it is essential to define the microbiome in the absence of disease. The digestive tract includes diverse habitats and hosts the human body’s greatest bacterial density. We describe the bacterial community composition of ten digestive tract sites from more than 200 normal adults enrolled in the Human Microbiome Project, and metagenomically determined metabolic potentials of four representative sites.

Results: The microbiota of these diverse habitats formed four groups based on similar community compositions: buccal mucosa, keratinized gingiva, hard palate; saliva, tongue, tonsils, throat; sub- and supra-gingival plaques; …

The Human Oral Microbiome, Floyd E. Dewhirst, Tuste Chen, Jacques Izard, Bruce J. Paster, Anne C. R. Tanner, Wen-Han Yu, Abirami Lakshmanan, William G. Wade

Department of Food Science and Technology: Faculty Publications

The human oral cavity contains a number of different habitats, including the teeth, gingival sulcus, tongue, cheeks, hard and soft palates, and tonsils, which are colonized by bacteria. The oral microbiome comprises over 600 prevalent taxa at the species level, with distinct subsets predominating at different habitats. The oral microbiome has been extensively characterized by cultivation and culture-independent molecular methods such as 16S rRNA cloning. Unfortunately, the vast majority of unnamed oral taxa are referenced by clone numbers or 16S rRNA GenBank accession numbers, often without taxonomic anchors. The first aim of this research was to collect 16S rRNA gene …

Killing Of Treponema Denticola By Mouse Peritoneal Macrophages, P. Gaibani, C. Vocale, S. Ambretti, F. Cavrini, Jacques Izard, L. Miragliotta, M. T. Pellegrino, V. Sambri

Department of Food Science and Technology: Faculty Publications

Treponema denticola has been identified as an important cause of periodontal disease and hypothesized to be involved in extra-oral infections. The objective of this study was to investigate the role of T. denticola cell length and motility during mouse peritoneal macrophages in vitro uptake. Macrophages, incubated under aerobic and anaerobic conditions, produced a similar amount of TNF-α when stimulated with Escherichia coli LPS. The uptake of FlgE- and CfpA-deficient mutants of T. denticola was significantly increased compared with the wild-type strain, due to cell size or lack of motility. Opsonization with specific antibodies considerably improved the treponemes’ uptake. …

Treponema Denticola In Disseminating Endodontic Infections, F. Foschi, Jacques Izard, H. Sasaki, V. Sambri, C. Prati, R. Müller, P. Stashenko

Department of Food Science and Technology: Faculty Publications

Treponema denticola is a consensus periodontal pathogen that has recently been associated with endodontic pathology. In this study, the effect of mono-infection of the dental pulp with T. denticola and with polymicrobial “red-complex” organisms (RC) (Porphyromonas gingivalis, Tannerella forsythia, and T. denticola) in inducing disseminating infections in wild-type (WT) and severe-combined-immunodeficiency (SCID) mice was analyzed. After 21 days, a high incidence (5/10) of orofacial abscesses was observed in SCID mice mono-infected with T. denticola, whereas abscesses were rare in SCID mice infected with the red-complex organisms or in wild-type mice. Splenomegaly was …

Periplasm Organization In Treponema Denticola As Studied By Cryo-Electron Tomography, Jacques Izard, C.-E. Hsieh, C. A. Mannella, Ronald J. Limberger, M. Marko

Department of Food Science and Technology: Faculty Publications

As a spirochete, the genus Treponema is one of the few major bacterial groups whose natural phylogenic relationships are evident at the level of gross phenotypic characteristics such as their morphology. Treponema spp. are highly invasive due to their unique motility in dense media, and their ability to penetrate cell layers. This feature is associated with the helical cell body and the presence of flagellar filaments in the periplasm. Treponema denticola is an oral pathogen involved in endodontic infections and periodontal diseases. The presence and quantity of T. denticola in the subgingival biofilm is correlated with the severity of periodontal …

Genetic And Structural Analyses Of Cytoplasmic Filaments Of Wild-Type Treponema Phagedenis And A Flagellar Filament-Deficient Mutant, Jacques Izard, William A. Samsonoff, Mary Beth Kinoshita, Ronald J. Limberger

Department of Food Science and Technology: Faculty Publications

Unique cytoplasmic filaments are found in the treponeme genus of spirochete bacteria. Their function is unknown, but their location underneath the periplasmic flagellar filaments (PFF) suggests a role in motility and/or cell structure. To better understand these unique structures, the gene coding for the cytoplasmic filaments, cfpA, was identified in various treponemal species. Treponema phagedenis cfpA was 2,037 nucleotides long, and the encoded polypeptide showed 78 to 100% amino acid sequence identity with the partial sequence of CfpA from T. denticola, T. vincentii, and T. pallidum subsp. pertenue. Wild-type T. phagedenis and a …

Insertional Inactivation Of Treponema Denticola Tap1 Results In A Nonmotile Mutant With Elongated Flagellar Hooks, Ronald J. Limberger, Linda L. Slivienski, Jacques Izard, William A. Samsonoff

Department of Food Science and Technology: Faculty Publications

The treponemal fla operon is comprised of numerous motility-related genes; however, the initial gene of this operon, tap1, has no known function. A recently developed system to generate specific mutants in Treponema denticola was utilized to determine if Tap1 was essential for motility. T. denticola tap1 and flanking DNA were identified, cloned, and sequenced, and a suicide plasmid that contained tap1 interrupted with an erythromycin resistance cassette (ermF and ermAM) was constructed. Because of potential polar effects from this cassette, a second plasmid that contained tap1 interrupted with a modified erythromycin resistance cassette that lacked the putative ermF transcription …