miniTurbo Proximity Labeling Analysis Service

What Is miniTurbo Proximity Labeling?

miniTurbo proximity labeling is a cell-based technique for identifying proteins located near a protein of interest. miniTurbo is an engineered biotin ligase derived from Escherichia coli BirA. It is fused to a target protein and expressed in living cells to enable proximity-dependent protein labeling.

 

In the presence of biotin and ATP, miniTurbo generates reactive biotin intermediates that covalently label nearby proteins, primarily at lysine residues. The labeled proteins are subsequently enriched using streptavidin and identified by mass spectrometry. This approach helps researchers profile the local protein environment of a target and identify candidate proximal proteins, including those involved in transient or dynamic cellular processes.

 

Branon, T. C. et al. Nat Biotechnol. 2018.

Figure 1. E. coli Biotin Ligase Structure (PDB: 2EWN) with Sites Mutated in TurboID (left) and miniTurbo (right) Shown in Red

When miniTurbo Proximity Labeling Is a Good Fit

miniTurbo is particularly relevant to studies that require protein neighborhood mapping in living cells.

1. Transient Protein Associations

Investigate proteins that may dissociate during cell lysis or conventional affinity purification.

2. Subcellular Protein Mapping

Characterize proteins near a target localized to a specific cellular compartment.

3. Size-Sensitive Targets

Use a smaller labeling enzyme when fusion-tag size is an important consideration.

4. Dynamic Cellular Processes

Profile nearby proteins associated with a defined biological event using an experimentally selected labeling window.

miniTurbo vs. TurboID vs. APEX2: How to Choose?

miniTurbo, TurboID, and APEX2 support proximity proteomics but differ in labeling chemistry, fusion-tag characteristics, and temporal resolution. The appropriate approach depends on the target protein, desired labeling window, and experimental system.

Comparison	miniTurbo	TurboID	APEX2
Labeling chemistry	Biotin ligase-mediated labeling	Biotin ligase-mediated labeling	Peroxidase-mediated labeling using biotin-phenol and H₂O₂
Approximate labeling radius	~10 nm	~10 nm	~20 nm
Main advantage	Smaller (~28 kDa) fusion tag and lower basal labeling background than TurboID	Efficient labeling of nearby proteins	Very rapid labeling, typically within approximately 1 minute
Main consideration	Relatively lower stability than TurboID	Fusion-tag effects and labeling background should be evaluated	Requires H₂O₂ and biotin-phenol; potential cellular toxicity must be considered
Suitable research priority	Smaller tag size and lower basal labeling background	Efficient capture of nearby proteins, including weak or transient associations	Rapidly changing cellular events requiring high temporal resolution

MtoZ Biolabs provides miniTurbo, TurboID, and APEX2 proximity labeling services. If the appropriate approach is unclear, contact our team to discuss the target protein, cell model, and experimental objectives.

miniTurbo Proximity Labeling Analysis Service at MtoZ Biolabs

MtoZ Biolabs provides an integrated miniTurbo proximity labeling workflow, covering construct preparation, cellular labeling, streptavidin-based protein enrichment, and mass spectrometry-based protein identification.

1. Construct Preparation and Cellular Labeling

Support miniTurbo vector construction, cell culture, target protein expression, biotin labeling, and Western blot verification.

 

2. Protein Enrichment and Mass Spectrometry

Enrich biotinylated proteins using streptavidin and analyze the recovered samples using Orbitrap-series high-resolution mass spectrometry. DDA or DIA acquisition is selected according to project requirements.

 

3. Protein Identification and Bioinformatics

Process MS data using MaxQuant, DIA-NN, or PEAKS against the UniProt reference database or a customer-provided database. Optional bioinformatics analysis includes GO/KEGG enrichment and protein interaction network construction.

 

Analysis Workflow

Figure 2. Workflow of miniTurbo Proximity Labeling Analysis

Applications

1. Subcellular Proteome Mapping

Characterize protein neighborhoods surrounding targets localized to specific cellular compartments.

2. Cell Signaling Research

Investigate local protein environments associated with selected signaling events.

3. Dynamic Protein Association Studies

Identify candidate proteins near a target during transient biological processes.

4. Protein Complex Characterization

Generate candidate lists for further investigation of proteins associated with a selected target or complex.

Sample Submission Suggestions

1. Sample Types

Cells expressing a miniTurbo fusion construct through transient transfection or stable expression. Projects requiring vector construction and target protein expression can also be assessed using target gene or construct information and the selected cell model.

 

2. Sample Quantity

• Recommended Input: At least 2×10⁷ cells per sample.
• Minimum Input: 1×10⁷ cells per sample, subject to project assessment.

3. Sample Handling

• Storage and Shipping:Submit frozen cell samples and ship on dry ice.
• Project Information:Provide the target protein identity, gene or construct information, cell model, expression status, and research objectives.
• Reference Database:Specify whether a UniProt reference database or a customer-provided database is preferred.

Please contact MtoZ Biolabs before shipment to confirm sample suitability, input requirements, and project-specific submission instructions.

Why Choose MtoZ Biolabs?

1. Customized Experimental Design

Experimental planning is tailored to the target protein, cell model, expression strategy, and research objectives, allowing project requirements to guide the labeling workflow.

 

2. Integrated Molecular Biology and Proteomics

Vector construction, cell expression, labeling verification, protein enrichment, and mass spectrometry analysis are covered within one service workflow.

 

3. Flexible Data Analysis Options

DDA/DIA acquisition and database-search workflows can be selected according to project requirements. Optional GO/KEGG enrichment and protein interaction network analysis are available for projects requiring additional biological interpretation.

 

4. One-Time Charge

Our pricing is transparent, with no hidden fees or additional costs.

 

Deliverables

1. Raw Mass Spectrometry Files

Original files generated during MS analysis.

2. Protein Identification Results

Excel file containing protein identification results.

3. Basic PDF Report

Summary of the experimental workflow and principal analytical findings.

4. Optional Bioinformatics Analysis

GO/KEGG enrichment and protein interaction network construction, when included in the project scope.

 

FAQ

Q1. Can miniTurbo proximity labeling confirm direct protein-protein binding?

No. miniTurbo identifies proteins located near the target protein under the tested conditions, but proximity does not establish direct binding. Chemical crosslinking mass spectrometry (XL-MS) or experiments using purified proteins may provide additional evidence for direct interactions.

 

Q2. What if the miniTurbo fusion affects target protein localization or function?

Fusion-tag effects should be considered during construct design and result interpretation. If the fusion changes target localization or function, the resulting proximity profile may not accurately represent the native protein environment. Discuss target-specific concerns with MtoZ Biolabs during project assessment.

 

Q3. Can miniTurbo proximity labeling be performed with limited cell numbers or primary cells?

The recommended input is at least 2 × 10⁷ cells per sample, with a minimum of 1 × 10⁷ cells subject to project assessment. Primary cell models require additional evaluation of fusion protein expression, labeling suitability, and available cell quantity. Please contact MtoZ Biolabs with your cell type and estimated sample amount to assess feasibility.

 

Contact Us

Planning a proximity labeling study for a target protein or a specific cellular process? Share your target protein information, cell model, expression status, and research objectives with MtoZ Biolabs. Our team can assess project requirements and help determine whether miniTurbo, TurboID, or APEX2 is the most appropriate approach for your study.

MtoZ Biolabs, an integrated chromatography and mass spectrometry (MS) services provider.

Related Services

Proximity Labeling Mass Spectrometry Service

TurboID Service