valinomycin

C2+ (Very Low Frequency - Technical Term)
UK/ˌvælɪnəʊˈmaɪsɪn/US/ˌvælɪnoʊˈmaɪsɪn/

Specialized/Technical

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Definition

Meaning

A naturally occurring dodecadepsipeptide antibiotic, known for its ability to transport potassium ions across cellular membranes.

A macrocyclic compound used in biochemistry and pharmacology as a potassium ionophore, which disrupts the ionic balance in cells, leading to the uncoupling of oxidative phosphorylation and cell death. It is a standard tool for studying membrane transport and mitochondrial function.

Linguistics

Semantic Notes

The word is primarily used as a mass noun (e.g., 'adding valinomycin'). It is a specific, concrete chemical entity named for its constituent amino acid (valine) and the suffix '-mycin' (from Greek *mykēs* 'fungus'), indicating its origin as a fungal metabolite.

Dialectal Variation

British vs American Usage

Differences

No significant lexical differences; spelling and pronunciation are consistent across varieties.

Connotations

None; purely technical term.

Frequency

Virtually identical, appearing exclusively in scientific literature and discourse.

Vocabulary

Collocations

strong
potassium ionophoremitochondrial uncouplerapply valinomycintreated with valinomycinvalinomycin-induced
medium
antibiotic valinomycinion transportmembrane potentialcellular toxicity
weak
study usingeffect ofsolution containingresearch on

Grammar

Valency Patterns

[Subject: Researcher/Protocol] + [Verb: add/apply/treat with] + valinomycin + [to Object: cells/mitochondria/suspension]Valinomycin + [Verb: acts as/functions as/causes/induces] + [Object: ionophore/uncoupling/depolarization]

Vocabulary

Synonyms

Neutral

potassium ionophore

Weak

ion transport antibioticmacrocyclic depsipeptide

Usage

Context Usage

Business

Not used.

Academic

Used in biochemistry, cell biology, pharmacology, and biophysics research papers and textbooks.

Everyday

Not used.

Technical

Core term in experimental protocols involving membrane potentials, ion transport, and mitochondrial bioenergetics.

Examples

By Part of Speech

adjective

British English

  • The valinomycin-treated mitochondria showed rapid depolarisation.
  • A valinomycin-sensitive potassium flux was recorded.

American English

  • The valinomycin-treated mitochondria showed rapid depolarization.
  • A valinomycin-sensitive potassium flux was recorded.

Examples

By CEFR Level

B2
  • Scientists use valinomycin to study how ions move across cell membranes.
  • The antibiotic valinomycin can disrupt the energy production of cells.
C1
  • Valinomycin acts as a highly selective potassium ionophore, collapsing the mitochondrial membrane potential by facilitating K+ uptake.
  • The experiment was controlled by adding valinomycin to the suspension, which uncoupled oxidative phosphorylation.

Learning

Memory Aids

Mnemonic

VALINOMYCIN: VALIne (the amino acid) + O (links parts) + MYCIN (like in 'fungus') – think 'a fungal-derived compound containing valine that works on ions.'

Conceptual Metaphor

A MOLECULAR TUNNEL/SHUTTLE (for potassium ions).

Watch out

Common Pitfalls

Translation Traps (for Russian speakers)

  • Do not confuse with 'валин' (valine) alone; the full term is 'валиномицин'.
  • The '-mycin' ending is standard for many antibiotics (e.g., стрептомицин), but it does not imply this is a macrolide like erythromycin.

Common Mistakes

  • Misspelling as 'valinomy*si*n' or 'valinomy*ci*n'.
  • Using it as a countable noun (e.g., 'a valinomycin').
  • Confusing it with other ionophores like gramicidin or nigericin.

Practice

Quiz

Fill in the gap
To dissipate the mitochondrial membrane potential in the assay, the researchers added to the medium.
Multiple Choice

What is the primary biochemical function of valinomycin?

FAQ

Frequently Asked Questions

Valinomycin is a dodecadepsipeptide, a cyclic compound made of twelve alternating amino acids and hydroxy acids.

It is a classic tool for studying bioenergetics because it selectively allows potassium ions to cross membranes, dissipating ion gradients and uncoupling mitochondria, which helps researchers understand membrane transport and energy coupling.

No, its high toxicity prevents clinical use. It is used exclusively as a research reagent in laboratory settings.

The name derives from one of its component amino acids, valine, and the suffix '-mycin', which is commonly used for antibiotics derived from fungi or bacteria (from Greek *mykēs*, meaning fungus).