Understanding a protein's function begins with knowing its partners. The discovery of novel protein-protein interactions (PPIs) is a crucial step in biological research, as it unlocks new pathways, identifies potential drug targets, and elucidates the complex mechanisms of diseases. However, finding these unknown connections is a significant challenge. Creative Biolabs' discovery of novel PPIs using phage display service provides a powerful, cell-free solution to this challenge. We utilize state-of-the-art phage display technology to screen vast libraries of proteins against your target, enabling you to identify novel, high-confidence binding partners that other methods may overlook. This advanced service bypasses the significant limitations of traditional methods.
This specialized solution is a key component of our comprehensive Phage Display Protein Interaction Mapping Service, which offers a complete suite of tools to explore and define complex biological networks.
Fig.1 The mechanism of the yeast two-hybrid (Y2H) system.1,3
Proteins are the workforce of the cell. They rarely act alone. To perform their functions, they must collaborate, forming complex and dynamic networks of protein interactions. These networks control virtually every process in a living organism, from cell division and signal transduction to metabolic regulation and immune responses. Identifying the specific partners in these networks is a central goal of modern biology. For decades, the yeast two-hybrid (Y2H) system has been a standard tool for this purpose. In this system, a known "bait protein" is tested against a "prey library" (a collection of potential partners) inside a living yeast cell. If the bait and prey proteins interact, they trigger a reporter gene, causing the yeast cell to, for example, change color. Figure 1 illustrates this key principle, showing how the interaction between bait (X) and prey (Y) activates the reporter gene. While useful, the Y2H system has many severe and well-known Y2H limitations:
These limitations mean that Y2H can only provide an incomplete and often misleading picture of a protein's interaction network. A more robust, flexible, and reliable method is required.
Phage display has emerged as the superior solution for mapping protein-protein interactions because it is a powerful cell-free system that decisively overcomes all the limitations of the yeast two-hybrid (Y2H) method. This approach eliminates the biological constraints of a living cell, enabling us to identify binding partners for any target protein, including those that are toxic or located in the cell membrane. Furthermore, you have complete control over the binding conditions (like pH and cofactors). You can use target proteins with specific post-translational modifications to identify partners that bind only to an activated state. By performing a cDNA library screening against billions of potential "prey" proteins, our platform delivers true high-throughput PPI discovery, identifying high-confidence interactors that other methods cannot find.
Fig.2 The workflow for constructing a phage display cDNA library.2,3
We have tailored our phage display platform to answer your specific research questions. Our services extend beyond simple detection, providing a nuanced understanding of your protein's interaction network.
This is our flagship service and the fastest way to build a complete interactome map from scratch. We answer the question, "What does my protein bind to in a specific cell, tissue, or organism?" by performing a comprehensive cDNA library screening using a high-complexity phage display cDNA library derived from your specific biological source. You receive a high-confidence list of all protein-protein interactions expressed in that sample.
This service reveals how cellular signaling controls protein interactions. We aim to find partners that bind to your protein when it is in a specific state, such as phosphorylated or ubiquitinated. By using your modified bait protein as the target, often in parallel with an unmodified control, we can identify binding partners that are strictly dependent on that specific post-translational modification.
Our in vitro platform excels at mapping partners for notoriously challenging targets, such as membrane proteins. We find the extracellular or intracellular binding partners of receptors, channels, or transporters. By using your full-length membrane protein as the bait protein for a cDNA library screening, we deliver a clean list of interactors.
This service fine-tunes your understanding of a known interaction. The goal is to find new proteins that bind to the samesite as a known ligand, antibody, or inhibitor. We first block your bait protein with the known molecule and then screen the prey library. This allows us to map specific binding regions and identify novel proteins that may compete for that same binding site in vivo.
We have streamlined the discovery process into five rigorous phases, ensuring transparency, quality, and actionable data.
It starts with a conversation. You will speak directly with our Ph.D. scientific team to define your project goals. We will discuss whether you are looking for any partners or only those with a very high affinity. We then establish the optimal target strategy. You can provide your purified target protein, or our expert team can express and purify it for you. We design the best immobilization method to ensure your protein's binding sites are exposed and active.
Based on your goal, we select the optimal library. For the discovery of novel protein-protein interactions, this is almost always a high-complexity phage display cDNA library representing the tissue of interest. We then perform 3-5 rounds of biopanning, an iterative process of binding, washing, and amplification. In each round, we can intensify the washing steps to select for the tightest and most specific binders. Learn more about our core Library Screening & Biopanning process.
After the final round of biopanning, we have a pool of phages that are highly enriched for those that bind to your target. We extract the DNA from this pool and use next-generation sequencing (NGS) to sequence millions of individual reads. This high-throughput PPI data provides a quantitative view of the results. We can identify which "prey" proteins are most enriched, providing a clear rank order of your top candidates.
Raw NGS data is just the beginning. Our bioinformatics team processes these millions of sequences. The cDNA fragments are translated into protein sequences and aligned against public databases to identify binding partners. The output is not merely a list of names; it is a detailed report displaying enrichment scores, fragment coverage, and domain information for each "hit."
You receive a comprehensive final report. This includes all raw data, the complete bioinformatics analysis, and a clear, ranked list of your protein's newly discovered binding partners.
A powerful, integrated technology suite supports all our services. This ensures quality, speed, and the ability to tackle even the most challenging projects.
We have two distinct platforms to handle any target protein.
The success of any screening project depends on the quality and diversity of the library. We offer a world-class selection.
We use the latest tools to ensure your data is robust and quantitative.
Choosing our platform gives you a distinct and decisive advantage in your research. We have engineered our services to deliver comprehensive, reliable, and actionable results.
Start discovering protein-protein interactions. Our phage display platform provides a proven, rapid, and high-throughput PPI solution to identify binding partners that traditional methods may overlook. to discuss your project and receive a no-obligation quote.
How is this service different from Yeast Two-Hybrid (Y2H)?
Our phage display service is an in vitro (cell-free) system, which is its main advantage. Y2H requires the protein interactions to occur inside a living yeast nucleus. This creates many Y2H limitations, such as failing to detect proteins that can't enter the nucleus (like membrane proteins), those that are toxic to yeast, or those requiring specific mammalian PTMs. Our platform bypasses these issues, enabling the discovery of a much broader and more biologically relevant range of partners.
What kind of bait protein do I need to provide?
You have flexible options. You can provide your own purified bait protein, or our expert protein expression team can produce and purify it for you. The bait can be a full-length protein, a specific domain, or even a short peptide. We routinely handle complex targets, such as proteins with specific PTMs or full-length membrane proteins stabilized in nanodiscs or liposomes. Our Ph.D. team will consult with you to determine the most effective bait strategy for your specific goal.
What is a Phage Display cDNA Library and why is it used?
A phage display cDNA library is the core discovery tool for this service. It is a vast collection of phages where each phage particle displays a different protein fragment on its surface. These fragments are generated from the total mRNA of a specific cell line or tissue. This prey library essentially represents the entire set of proteins expressed in that biological sample, allowing us to perform an unbiased cDNA library screening to identify binding partners for your protein.
References:
Please kindly note that our services can only be used to support research purposes (Not for clinical use).
Creative Biolabs is a globally recognized phage company. Creative Biolabs is committed to providing researchers with the most reliable service and the most competitive price.
