''Porphyromonas'' is a

Gram-negative Gram-negative bacteria are bacteria that do not retain the crystal violet stain used in the Gram staining method of bacterial differentiation. They are characterized by their cell envelopes, which are composed of a thin peptidoglycan cell wall ...

, non-

spore In biology, a spore is a unit of sexual or asexual reproduction that may be adapted for dispersal and for survival, often for extended periods of time, in unfavourable conditions. Spores form part of the life cycles of many plants, algae, f ...

-forming, obligately

anaerobic Anaerobic means "living, active, occurring, or existing in the absence of free oxygen", as opposed to aerobic which means "living, active, or occurring only in the presence of oxygen." Anaerobic may also refer to: * Anaerobic adhesive, a bonding a ...

and non-motile genus from the family of

Porphyromonadaceae ''Porphyromonadaceae'' is a family of bacteria Bacteria (; singular: bacterium) are ubiquitous, mostly free-living organisms often consisting of one Cell (biology), biological cell. They constitute a large domain (biology), domain of pro ...

. There were 16 different Porphyromonas species documented as of 2015 which reside in both animal and human reservoirs. It was discovered more recently that Porphyromonas also exist with the environment, albeit to a lower extent. This genus is notably implicated in the modulation of oral cavity, respiratory tract, and gastrointestinal tract disease states. It is suggested that Porphyromonas either operate as benign bacteria pertinent to host immunity or are potential pathobionts that opportunistically provoke diseased states when homeostasis is disrupted. Despite its characterization not being fully elucidated due to sparse research, various studies report the prevalence of this genus at 58.7% in healthy states compared with 41.3% in diseased states. This genus was first reported in the oral cavity and is found specifically in the salivary microbiome. Porphyromonas are also commonly found in the microbiome of the human digestive tract, as shown by the

Human Microbiome Project The Human Microbiome Project (HMP) was a United States National Institutes of Health (NIH) research initiative to improve understanding of the microbiota involved in human health and disease. Launched in 2007, the first phase (HMP1) focused on ...

in general.

Distribution of Species

While overlap exists between humans and animals in the distribution of Porphyromonas species, some species are more prevalent in each.

Humans

''P. asaccharolytica'', ''P. endodontalis'', ''P. gingivalis'', ''P. catoniae'', ''P. pasteri'', ''P. somerae'', and ''P. uenonis''

Animals

''P. cangingivalis'', ''P. canoris'', ''P. cansulsi'', ''P. circumdentaria'', ''P. crevioricanis'', ''P. gingivicanis'', ''P. salivosa'', ''P. macacae'', ''P. gulae'', and ''P. levii''

Environment

Porphyromonas have been isolated from manmade and naturally occurring environments. Most of these species have been detected in manmade environments including transportation systems, healthcare settings, and indoor facilities; Porphyromonas persist in naturally occurring environments such as air, soil, seawater, freshwater, agricultural sites, and alpine meadows to a lesser extent. Furthermore, waste-management sites are a pertinent source of environment-dwelling species. Specific environmentally hosted strains have not been widely studied or identified.

Health Impacts

Oral Cavity

* '' P. ginvigalis:'' a gram-negative anaerobe and pathological agent of

periodontitis Periodontal disease, also known as gum disease, is a set of inflammatory conditions affecting the tissues surrounding the teeth. In its early stage, called gingivitis, the gums become swollen and red and may bleed. It is considered the main cau ...

Gastrointestinal Tract

* Overabundance of this genus has been reported from the feces of patients diagnosed with colorectal cancer.

Respiratory Tract

* Porphyromonas increase has been associated with

pulmonary tuberculosis Tuberculosis (TB) is an infectious disease usually caused by '' Mycobacterium tuberculosis'' (MTB) bacteria. Tuberculosis generally affects the lungs, but it can also affect other parts of the body. Most infections show no symptoms, in ...

lesions.

Uterine Tract

* '' P. levii:'' bacteria of high abundance in cows with uterine disease.

Other

Alterations in Porphyromonas abundance have also been associated with various cancers, autoimmune and neurodegenerative conditions, vaginal diseases,

rheumatoid arthritis Rheumatoid arthritis (RA) is a long-term autoimmune disorder that primarily affects joints. It typically results in warm, swollen, and painful joints. Pain and stiffness often worsen following rest. Most commonly, the wrist and hands are involv ...

, and Sjogren's syndrome.

Detection Methods

Porphyromonas is most commonly detected via utilization of 16s rRNA sequencing techniques.