Toolkit/liquid chromatography-tandem mass spectrometry (LC-MS/MS)

liquid chromatography-tandem mass spectrometry (LC-MS/MS)

Assay Method·Research·Since 2026

Also known as: LC-MS/MS

Taxonomy: Technique Branch / Method. Workflows sit above the mechanism and technique branches rather than replacing them.

Summary

We confirmed metabolite accumulation using liquid chromatography-tandem mass spectrometry (LC-MS/MS) and generated putative reference spectra for 102 metabolites for which no MS2 data had previously been available.

Usefulness & Problems

Why this is useful

LC-MS/MS was used in this study to confirm metabolite accumulation and to generate putative reference spectra for metabolites lacking prior MS2 data.; confirming metabolite accumulation; obtaining MS2 data for metabolite identification; generating putative reference spectra

Source:

LC-MS/MS was used in this study to confirm metabolite accumulation and to generate putative reference spectra for metabolites lacking prior MS2 data.

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confirming metabolite accumulation

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obtaining MS2 data for metabolite identification

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generating putative reference spectra

Problem solved

It provides a higher-confidence follow-up measurement for metabolite accumulation and expands spectral coverage for poorly characterized metabolites.; provides confirmatory metabolite measurement and spectral information for metabolites lacking prior MS2 data

Source:

It provides a higher-confidence follow-up measurement for metabolite accumulation and expands spectral coverage for poorly characterized metabolites.

Source:

provides confirmatory metabolite measurement and spectral information for metabolites lacking prior MS2 data

Problem links

provides confirmatory metabolite measurement and spectral information for metabolites lacking prior MS2 data

Literature

It provides a higher-confidence follow-up measurement for metabolite accumulation and expands spectral coverage for poorly characterized metabolites.

Source:

It provides a higher-confidence follow-up measurement for metabolite accumulation and expands spectral coverage for poorly characterized metabolites.

Published Workflows

The metabolome of an E. coli CRISPRi library identifies benefits of minimal metabolite levels and targets for engineering.

2026

Objective: Map metabolome responses across a genome-scale E. coli CRISPRi library to identify metabolites normally maintained at low levels, understand why minimal metabolite pools are beneficial, and find targets for metabolic engineering.

Why it works: The workflow perturbs metabolic genes across many CRISPRi strains, detects metabolite accumulation phenotypes, and then confirms selected metabolite changes by LC-MS/MS, allowing inference about metabolites that are normally kept at low levels and identification of engineering targets.

substrate-level regulation of enzyme activitycompetitive inhibition avoidancesuppression of side reactionsmetabolic bottleneck relief by increasing farnesyl diphosphate levelsCRISPRi library perturbationmetabolome profilingLC-MS/MS confirmation

Stages

  1. 1.
    CRISPRi library metabolome profiling(broad_screen)

    This stage provides broad perturbation coverage to discover which gene knockdowns cause accumulation of metabolites that are usually kept at low levels.

    Selection: Measure metabolome responses across CRISPRi strains targeting genes in the iML1515 metabolic model to find strains with metabolite accumulation phenotypes.

  2. 2.
    LC-MS/MS confirmation and spectral generation(confirmatory_validation)

    This stage validates metabolite accumulation observations from the broader screen and adds reference-like MS2 information for poorly characterized metabolites.

    Selection: Confirm metabolite accumulation and generate putative reference spectra for metabolites lacking prior MS2 data.

  3. 3.
    Engineering example in a synthetic carotenoid pathway(functional_characterization)

    This stage demonstrates that the metabolome findings can identify actionable engineering targets for improving flux through an engineered pathway.

    Selection: Test whether relieving a low-metabolite bottleneck by IspB knockdown increases farnesyl diphosphate levels and carotenoid production.

Taxonomy & Function

Primary hierarchy

Technique Branch

Method: A concrete measurement method used to characterize an engineered system.

Target processes

No target processes tagged yet.

Implementation Constraints

cofactor dependency: cofactor requirement unknownencoding mode: genetically encodedimplementation constraint: context specific validationimplementation constraint: multi component delivery burdenoperating role: sensorswitch architecture: multi component

This method requires liquid chromatography-tandem mass spectrometry capability and a workflow for interpreting MS2 spectra.; requires LC-MS/MS instrumentation and metabolite standards or annotation workflow sufficient to generate putative reference spectra

The abstract does not show that LC-MS/MS alone explains why metabolites are kept low or how to engineer all affected pathways.; the abstract does not specify instrument settings, identification confidence criteria, or whether spectra were publicly deposited

Validation

Cell-freeBacteriaMammalianMouseHumanTherapeuticIndep. Replication

Supporting Sources

Ranked Claims

Claim 1method outputsupports2026Source 1needs review

LC-MS/MS confirmed metabolite accumulation and enabled generation of putative reference spectra for 102 metabolites lacking previous MS2 data.

We confirmed metabolite accumulation using liquid chromatography-tandem mass spectrometry (LC-MS/MS) and generated putative reference spectra for 102 metabolites for which no MS2 data had previously been available.
metabolites with new putative reference spectra 102 metabolites

Approval Evidence

1 source1 linked approval claimfirst-pass slug liquid-chromatography-tandem-mass-spectrometry-lc-ms-ms
We confirmed metabolite accumulation using liquid chromatography-tandem mass spectrometry (LC-MS/MS) and generated putative reference spectra for 102 metabolites for which no MS2 data had previously been available.

Source:

method outputsupports

LC-MS/MS confirmed metabolite accumulation and enabled generation of putative reference spectra for 102 metabolites lacking previous MS2 data.

We confirmed metabolite accumulation using liquid chromatography-tandem mass spectrometry (LC-MS/MS) and generated putative reference spectra for 102 metabolites for which no MS2 data had previously been available.

Source:

Comparisons

Source-stated alternatives

The abstract does not explicitly name alternative confirmation assays.

Source:

The abstract does not explicitly name alternative confirmation assays.

Source-backed strengths

used here to confirm metabolite accumulation; enabled generation of putative reference spectra for 102 metabolites

Source:

used here to confirm metabolite accumulation

Source:

enabled generation of putative reference spectra for 102 metabolites

Compared with assays

The abstract does not explicitly name alternative confirmation assays.

Shared frame: source-stated alternative in extracted literature

Strengths here: used here to confirm metabolite accumulation; enabled generation of putative reference spectra for 102 metabolites.

Relative tradeoffs: the abstract does not specify instrument settings, identification confidence criteria, or whether spectra were publicly deposited.

Source:

The abstract does not explicitly name alternative confirmation assays.

Ranked Citations

  1. 1.
    StructuralSource 1MED2026Claim 1

    Extracted from this source document.