Recording-2025-03-01T14_14_14.606Z

Human Microbiome

The sum total of all microbes found on and in a normal human, critically important to the health and functioning of its host organism.

Human Microbiome Project

An American effort to characterize the microbes living on the human body and their health implications during various disease processes.

Normal Biota

Microbes that help keep pathogenic organisms in check, digest food, and metabolize substances that humans cannot use.

Infection

When microbes get past host defenses, enter tissues, and multiply.

Disease

A deviation from health, which does not necessarily mean it is caused by a microbe.

Pathogen

A microbe whose relationship with its host is parasitic and results in infection and disease.

Pathogenicity

An organism's potential to cause disease.

Opportunistic Pathogens

Pathogens that cause disease when host defenses are compromised or when they occupy a location in the body that is not natural to them.

Virulence

An organism's ability to establish itself in the host and cause damage.

Microbial Antagonism

A relationship in which microorganisms compete for survival in a common environment by inhibiting or destroying another organism.

Commensalism

An unequal relationship where one organism benefits while the other is neither helped nor harmed.

Mutualism

An obligatory relationship that is mutually beneficial for both organisms involved.

Exoenzymes

Enzymes secreted by microbes that break down and inflict damage on host tissues.

Exotoxins

Proteins secreted by bacteria, usually with strong specificity for a target cell, that can cause severe damage.

Endotoxins

Part of the outer membrane of gram-negative bacteria that causes systemic effects upon release.

Infectious Dose

The minimum number of microbes necessary to cause an infection.

Phagocytes

White blood cells like neutrophils and macrophages that destroy pathogens through endocytosis.

Hyaluronidase

An enzyme that breaks down hyaluronic acid, allowing bacteria to spread into surrounding tissues.

Mucinase

An enzyme that digests the protective coating of mucous membranes.

Coagulase

An enzyme that causes blood clotting, allowing microbes to hide within clots.

Kinase

An enzyme that dissolves fibrin clots, allowing microbes to invade deeper into tissues.