nitrogenase
LowTechnical, Scientific
Definition
Meaning
An enzyme that catalyzes the reduction of atmospheric nitrogen (N₂) to ammonia (NH₃).
In biochemistry and microbiology, any of several enzyme complexes, such as MoFe-protein or Fe-protein, found in nitrogen-fixing bacteria and archaea that perform the energy-intensive biological nitrogen fixation process essential for the nitrogen cycle.
Linguistics
Semantic Notes
The term is highly specific to biochemistry, microbiology, and agronomy. It refers to the functional protein complex, not the process (nitrogen fixation) or the organisms (nitrogen-fixers). Often described by its metal cofactors (e.g., molybdenum-nitrogenase).
Dialectal Variation
British vs American Usage
Differences
No significant lexical or spelling differences. Both varieties use the same term identically.
Connotations
Purely scientific term with no regional connotative differences.
Frequency
Equally low frequency and confined to technical contexts in both regions.
Vocabulary
Collocations
Grammar
Valency Patterns
The nitrogenase [VERB] nitrogen.Nitrogenase is [ADJECTIVE].Vocabulary
Synonyms
Neutral
Weak
Vocabulary
Antonyms
Phrases
Idioms & Phrases
- “None.”
Usage
Context Usage
Business
Not used.
Academic
Used in biochemistry, microbiology, plant science, and environmental science papers and textbooks.
Everyday
Virtually never used.
Technical
Core term in research on nitrogen fixation, soil science, and agricultural biotechnology.
Examples
By Part of Speech
adjective
British English
- The nitrogenase component was purified.
- Nitrogenase activity was measured.
American English
- The nitrogenase complex was isolated.
- Nitrogenase function is oxygen-sensitive.
Examples
By CEFR Level
- Some bacteria in the soil have an enzyme called nitrogenase.
- Nitrogenase allows certain bacteria to convert atmospheric nitrogen into a form plants can use.
- The activity of the molybdenum-iron nitrogenase complex is severely inhibited by the presence of oxygen.
Learning
Memory Aids
Mnemonic
Think: 'NITROGEN-ase' – the 'ase' ending tells you it's an enzyme that works on nitrogen.
Conceptual Metaphor
A biological machine / catalyst for breaking the powerful triple bond in N₂.
Watch out
Common Pitfalls
Translation Traps (for Russian speakers)
- Do not confuse with 'нитрогеназа' (direct transliteration, correct). Avoid calquing as 'азотный фермент' (Nitrogen enzyme) which is less precise.
Common Mistakes
- Misspelling as 'nitrogenise' (which is a verb meaning to treat with nitrogen).
- Pronouncing it /naɪˈtrɒdʒ.ə.neɪz/ with stress on the second syllable.
- Using it to refer to the bacteria instead of the enzyme.
Practice
Quiz
What is the primary function of nitrogenase?
FAQ
Frequently Asked Questions
Only certain prokaryotes—specific bacteria and archaea, often living symbiotically in root nodules of legumes or freely in soil.
It drives biological nitrogen fixation, converting inert N₂ gas into bioavailable ammonia, which is crucial for all life as it fertilises ecosystems and supports agriculture.
Yes. The most common contains molybdenum and iron (MoFe-protein), but alternative forms use vanadium or only iron.
No. It is only produced by certain microorganisms. Engineering crop plants to produce their own nitrogenase is a major goal of agricultural research.