Microbiology Glossary
Browse our comprehensive collection of 777 microbiology terms and definitions.
A
ATP
Adenosine triphosphate ATP is a nucleotide that serves as the main energy carrier in living cells. It consists of the nitrogenous base adenine, the sugar...
Atrichous
Bacterial cells lacking flagella, rendering them non‑motile. Explanation Atrichous bacteria are defined by the absence of flagella—whip‑like appendages used...
Attack Rate
The attack rate is the proportion of an at‑risk population that develops a disease over the course of an outbreak or defined period. It is calculated as the...
Australian Bat Lyssavirus
Australian bat lyssavirus is a species of lyssavirus endemic to bats in Australia that causes fatal rabies-like encephalitis in bats, humans and other mammals....
Autoimmunity
Autoimmunity is the process by which the immune system mounts a response against the body’s own tissues, recognizing self‑antigens as foreign and leading to...
Autotroph
An autotroph is an organism that synthesizes organic molecules from inorganic carbon sources, usually carbon dioxide, using energy from light or chemical reactions.
Axenic Culture
An axenic culture is a laboratory culture containing a single microbial species grown free of all other living organisms, including bacteria, fungi, protozoa...
B
Bacillus
Bacillus is a genus of Gram‑positive, rod‑shaped bacteria that form protective endospores. Members of this group are aerobic or facultatively anaerobic and...
Bacillus
Bacillus is a genus of Gram-positive, rod-shaped bacteria capable of forming a single durable endospore within each cell. These bacteria are aerobes or...
Bacillus anthracis
Bacillus anthracis is a Gram-positive rod-shaped bacterium best known as the cause of anthrax. Unlike most members of the genus Bacillus, it is an obligate...
Bacillus anthracis
Bacillus anthracis is a Gram‑positive, rod‑shaped bacterium that causes anthrax. It forms tough endospores that can remain dormant in soil for decades, and it...
Bacteremia
Bacteremia refers to the presence of bacteria circulating in the bloodstream. In many cases it is transient and harmless, occurring after activities like...
Bacteria
Bacteria are microscopic single‑celled organisms without a membrane‑bound nucleus. They belong to the domain Bacteria and are prokaryotes, meaning their DNA...
Bacteria
Bacteria are microscopic single‑celled organisms that inhabit virtually every environment on Earth. These prokaryotes lack a true nucleus and membrane‑bound...
Bacteria
Bacteria are tiny single-celled organisms. They inhabit nearly every environment, from soil and water to the human body, and have diverse roles, some...
Bacterial
The term 'bacterial' is an adjective used to describe anything pertaining to bacteria. It can refer to cells, structures, infections, cultures or processes...
Bacterial Culture
A bacterial culture is a laboratory method for growing bacteria in a controlled environment. It involves placing bacterial cells onto or into a nutrient medium...
Bactericidal
The term 'bactericidal' describes substances or actions that kill bacteria. It is often used to characterise antibiotics, disinfectants or processes that...
Bacteriology
Bacteriology is the scientific study of bacteria. It focuses on the classification, structure and metabolic processes of bacterial organisms. By understanding...
Bacteriophage
Bacteriophages, often called phages, are viruses that infect bacteria. They consist of a protein coat surrounding a DNA or RNA genome and cannot replicate...
Bacteriophage Typing
Bacteriophage typing is a phenotypic method used to distinguish strains of bacteria based on their susceptibility to lysis by a defined set of bacteriophages....
Bacteriostatic
Bacteriostatic refers to substances that inhibit the growth and reproduction of bacteria without killing them. These agents hold bacterial populations in...
Bacteriuria
Bacteriuria describes the presence of bacteria in urine. It may reflect contamination from the urethra or signify infection of the urinary tract. Explanation...
Balanced Growth
Balanced growth describes a state in which a microbial population grows exponentially with all cellular constituents increasing at the same relative rate,...