lipopolysaccharide
C1+Technical/Scientific
Definition
Meaning
A large molecule consisting of a lipid and a polysaccharide, found in the outer membrane of Gram-negative bacteria.
In immunology and microbiology, it is a major component of the bacterial cell wall that acts as an endotoxin, triggering strong immune responses and inflammation when released.
Linguistics
Semantic Notes
Always a noun in its primary usage. It is a compound noun formed from three morphemes (lipo- + poly- + saccharide), which makes its meaning partially transparent to those familiar with scientific terminology.
Dialectal Variation
British vs American Usage
Differences
No significant lexical differences. Both use the same term. Spelling is consistent.
Connotations
Identical connotations in scientific contexts.
Frequency
Equally rare outside of microbiology, immunology, biochemistry, and related fields.
Vocabulary
Collocations
Grammar
Valency Patterns
the lipopolysaccharide of [bacterium]lipopolysaccharide-induced [effect]lipopolysaccharide from [source]Vocabulary
Synonyms
Strong
Neutral
Weak
Vocabulary
Antonyms
Usage
Context Usage
Academic
Frequently used in research papers in microbiology, immunology, and pharmacology.
Everyday
Virtually never used in everyday conversation.
Technical
Core term in microbiology and immunology labs, medical literature, and pharmaceutical development.
Examples
By Part of Speech
adjective
British English
- The lipopolysaccharide content was measured.
- A lipopolysaccharide-rich environment.
American English
- LPS-induced fever.
- A lipopolysaccharide-based assay.
Examples
By CEFR Level
- Lipopolysaccharide is a toxin found in some bacteria.
- Scientists study lipopolysaccharide to understand infections.
- The release of lipopolysaccharide from the bacterial wall triggers a severe inflammatory response.
- Researchers purified the lipopolysaccharide to analyse its specific carbohydrate moieties.
Learning
Memory Aids
Mnemonic
Think: LIPO (fat) + POLY (many) + SACCHARIDE (sugar). It's a molecule with a fat part attached to a long chain of sugars.
Conceptual Metaphor
A bacterial 'alarm signal' or 'trigger' for the immune system.
Watch out
Common Pitfalls
Translation Traps (for Russian speakers)
- The English word is a direct calque of the Russian 'липополисахарид'. There is no trap; it's a direct equivalent.
Common Mistakes
- Misspelling as 'lipopolisaccharide' (one 'l') or 'lipopolysacharide' (one 'c'). Confusing it with 'lipoprotein'.
Practice
Quiz
Lipopolysaccharide is primarily associated with which type of bacteria?
FAQ
Frequently Asked Questions
Lipopolysaccharide (LPS) is the major component of the endotoxin of Gram-negative bacteria. The terms are often used interchangeably, but endotoxin technically refers to the biologically active complex of which LPS is a part.
It is a core term in microbiology, immunology, medical research, toxicology, and pharmaceutical development, particularly relating to sepsis, inflammation, and vaccine research.
It is generally treated as an uncountable (mass) noun in scientific writing (e.g., 'the amount of lipopolysaccharide'), though it can be countable when referring to types or molecules (e.g., 'different lipopolysaccharides').
The standard abbreviation is LPS, which is universally used in scientific literature.