Microbiology Glossary
Browse our comprehensive collection of 777 microbiology terms and definitions.
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Lancefield Classification
The Lancefield classification is a serological system that groups beta hemolytic streptococci based on the antigenic carbohydrate composition of their cell...
Lassa Virus
Lassa virus is an Old World arenavirus that causes Lassa fever, an acute viral haemorrhagic illness endemic to West Africa. The virus is an enveloped,...
Latent
Latent refers to a state in which an organism, virus or trait is present but not currently active or expressing. In microbiology, latent phases are periods of...
Latent Infection
A latent infection is a state in which a pathogen persists within a host without active replication or clinical symptoms. The organism remains viable and...
Latex Agglutination Test
A latex agglutination test is a rapid immunoassay that uses polystyrene latex particles coated with specific antibodies or antigens. When mixed with a sample...
Lethal
Lethal describes something that causes death. In microbiology and genetics, lethal factors are genes, mutations, organisms or doses of agents that result in...
Lethal Dose (LD)
Lethal dose LD is the quantity of a substance, toxin, radiation or infectious agent that causes death in a specified proportion of a test population. The most...
Lichen
Definition A lichen is a stable mutualistic association between a filamentous fungus the mycobiont and one or more photosynthetic partners the photobiont,...
Light Microscope
A light microscope is an optical instrument that uses visible light and a series of lenses to magnify small specimens. It allows researchers to observe...
Liquid Media
Liquid media are nutrient-rich solutions formulated to support the growth of microorganisms in a homogeneous suspension. They provide water, carbon, nitrogen,...
Listeria monocytogenes
Listeria monocytogenes is a Gram-positive, facultatively anaerobic bacterium that causes the foodborne infection listeriosis. It has the remarkable ability to...
LPS
LPS lipopolysaccharide is a major glycolipid component of the outer membrane of Gram negative bacteria. It consists of a hydrophobic lipid A region anchored in...
Lujo Virus
Lujo virus is a novel Old World arenavirus associated with a small outbreak of severe hemorrhagic fever in Zambia and South Africa in 2008. The enveloped virus...
Lymphocytic Choriomeningitis Virus (LCMV)
Lymphocytic choriomeningitis virus LCMV is an Old World arenavirus that causes lymphocytic choriomeningitis, a typically mild disease characterized by fever...
Lyon IARC polyomavirus (LIPyV)
Lyon IARC polyomavirus LIPyV is a circular double‑stranded DNA virus first reported in 2017 in skin swabs from human volunteers. Its genome of about 5.3...
Lyophilization
Lyophilization, or freeze-drying, is a dehydration process that removes water from a frozen product by sublimation under reduced pressure. It is used to...
Lysogeny
Lysogeny is a stable association between a temperate bacteriophage and its bacterial host in which the phage genome integrates into the host chromosome or...
Lysozyme
Lysozyme is a muramidase enzyme that cleaves the β1→4 glycosidic bond in peptidoglycan, weakening bacterial cell walls and causing lysis. It is found in bodily...
Lytic Cycle
The lytic cycle is the replicative strategy of bacteriophages and some eukaryotic viruses in which the infected host cell is destroyed and progeny virions are...
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MacConkey Agar
MacConkey agar is a selective and differential culture medium formulated to isolate Gram‑negative bacteria and distinguish them based on their ability to...
Machupo Virus
Machupo virus is a New World arenavirus responsible for Bolivian hemorrhagic fever. This enveloped virus has a bi-segmented, negative-sense RNA genome and is...
Macrophage
A macrophage is a large phagocytic cell derived from a monocyte that engulfs and digests cellular debris, pathogens and foreign particles as part of the innate...
Malawi polyomavirus (MWPyV/HPyV10)
Malawi polyomavirus MWPyV, also known as human polyomavirus 10 or Mexico polyomavirus, is a non‑enveloped double‑stranded DNA virus that infects humans. It was...
MALDI-TOF
MALDI‑TOF is an acronym for matrix‑assisted laser desorption/ionization time‑of‑flight, a mass spectrometry technique used to determine the mass‑to‑charge...