Invasion of periodontal pathogens into periodontal tissues is an important step that can cause tissue destruction in periodontal diseases. Porphyromonas gingivalis is a keystone pathogen and its gingipains are key virulence factors. Fusobacterium nucleatum is a bridge organism that mediates coadhesion of disease-causing late colonizers such as P. gingivalis and early colonizers during the devel...

Porphyromonas gingivalis is one of the major causative agents of adult periodontitis. One of the features of this periodontal pathogen is its ability to attach to a variety of oral bacterial surfaces and to colonize subgingival dental plaque. We have shown that Streptococcus cristatus CC5A inhibits expression of fimA, a gene encoding the major protein subunit of long fimbriae in P. gingivalis; ...

Porphyromonas gingivalis (P. gingivalis) is a major oral pathogen and associated with periodontal diseases including periodontitis and alveolar bone loss. In this review, we indicate that two virulence factors, which are hemoglobin receptor protein (HbR) and cysteine proteases "gingipains", expressed by P. gingivalis have novel functions on the pathogenicity of P. gingivalis. P. gingivalis prod...

Amoebiasis continues to be a major cause of morbidity and mortality in children in developing countries. Entamoeba histolytica infections are commonly observed in tropical and subtropical regions of the world including Iran. In developed countries Entamoeba histolytica infections are commonly seen in travelers, recent immigrants, homosexual men, and inmates of institutions. The disease is more ...

Entamoeba possesses a highly divergent mitochondrion-related organelle known as the mitosome. Here, we report the discovery of a novel protein in Entamoeba, which we name Mitosomal β-barrel Outer Membrane Protein of 30 kDa (MBOMP30). Initially identified through in silico analysis, we experimentally confirmed that MBOMP30 is indeed a β-barrel protein. Circular dichroism analysis showed MBOMP30 ...

Homologous recombination (HR) has not been demonstrated in the parasitic protists Entamoeba histolytica or Entamoeba invadens, as no convenient method is available to measure it. However, HR must exist to ensure genome integrity, and possible genetic exchange, especially during stage conversion from trophozoite to cyst. Here we show the up regulation of mitotic and meiotic HR genes in Entamoeba...

The ability to attach to a variety of oral surfaces is an important characteristic of Porphyromonas gingivalis. Previous studies have demonstrated that expression and production of FimA, a major subunit protein of the long fimbriae, is required for P. gingivalis colonization. Here we report that a surface protein, arginine deiminase (ArcA) of Streptococcus cristatus, represses FimA production a...

Recent epidemiological studies revealed a significant association between oral squamous cell carcinoma (OSCC) and Porphyromonas gingivalis, a major pathogen of periodontal disease. As a keystone pathogen of periodontitis, P. gingivalis is known not only to damage local periodontal tissues, but also to evade the host immune system and eventually affect systemic health. However, its role in OSCC ...

BACKGROUND Periodontitis (PD) has been reported to be associated with rheumatoid arthritis (RA). Porphyromonas gingivalis (P. gingivalis) is a gram-negative anaerobic bacterium that is recognized as one of the major pathogenic organisms in PD and is the only bacterium known to express peptidylarginine deiminase (PAD). Antibody against human α-enolase (ENO1) is one of the autoantibodies in RA. E...

The association of vascular reactivity between diabetes and periodontal disease has not been clarified. Gingival blood flow was measured by laser Doppler flowmetry for 31 weeks in Wistar rats, Wistar rats orally challenged with Porphyromonas gingivalis (Wistar rats + Porphyromonas gingivalis), Goto-Kakizaki rats, and Goto-Kakizaki rats orally challenged with Porphyromonas gingivalis (Goto-Kakiz...