Microbiome

Microbiota

The community of microorganisms living in a specific environment, often consisting of multiple species and various types of microorganisms.

Microbiome

Refers to all the genes present within a microbial community.

Endogenous microorganism

Naturally occurring microorganisms in a given environment that are part of the natural microbiota.

Exogenous microorganisms

Microorganisms not naturally found in the microbiota but introduced from external sources.

Commensal microorganism

Part of the normal microbiota that provide beneficial effects to the body without causing harm.

Pathogenic microorganisms

Exogenous microorganisms that cause diseases and harm to the host.

Opportunistic pathogens

Microorganisms that are normally part of the endogenous microbiota but cause infections under specific conditions.

Colonisation

The process of acquiring microbiota, influenced by factors like diet, hygiene, and genetics.

Firmicutes

Gram-positive bacteria, abundant in the mouth, esophagus, stomach, and colon.

Bacteroidetes

Gram-negative bacteria found in large quantities in the colon, alongside Firmicutes.

Actinobacteria

Gram-positive bacteria primarily found in larger amounts on the skin.

Proteobacteria

Gram-negative bacteria mainly present on the skin, including Betaproteobacteria and Gammaproteobacteria.

Malassezia spp.

Fungal species commonly found on the skin, associated with dandruff and dermatitis.

Candida spp.

Fungal species found in the gut, mouth, and vagina, causing Candidiasis.

Respiratory tract microbiota

Bacteria present in areas like the nose and larynx, including Staphylococci and Streptococci.

Urogenital tract microbiota

Bacteria colonizing the distal urethra, including Escherichia coli and Proteus mirabilis.

Vaginal microbiota

Changes throughout a woman's life, dominated by different bacteria before and after puberty.

Gastrointestinal tract microbiota

Diverse bacteria present in different gut regions, aiding in digestion and nutrient extraction.

Antibiotics and Gut Microbiota

Antibiotics can alter the gut microbiota by eliminating competing bacteria, allowing opportunistic pathogens to thrive temporarily, but the normal microbiota usually recolonizes quickly to outcompete pathogens and restore gut health.

Dysbiosis

Dysbiosis refers to diseases caused by microbial imbalances, such as breakdown of tight junctions leading to inflammatory bowel disease, obesity, oral diseases like periodontal disease, skin conditions like Acne Vulgaris, and vaginal issues like vaginitis and vaginosis.

Virome

The virome consists of highly abundant and fast-mutating genetic elements, estimated to have 10 times more virus-like particles than bacteria in and on the human body, including eukaryotic viruses, bacteriophages affecting bacterial microbiota, and virus-derived genetic elements like prophages and endogenous retroviruses.

Virome Dynamics

The virome changes rapidly over time, influencing the microbial balance and health of the host.